diff --git a/CHANGELOG.md b/CHANGELOG.md
index af8ab0fa26..88e256e887 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,10 @@
 
 Multiple minor updates were made to the ARKODE package.  We removed an extraneous
 copy of the output vector when using ARKODE in `ARK_ONE_STEP` mode.  We added the
+function `ARKodeGetStageIndex` that returns the index of the stage currently
+being processed, and the total number of stages in the method, for users who must
+compute auxiliary quantities in their IVP right-hand side functions during some
+stages and not others (e.g., in all but the first or last stage). We added the
 function `ARKodeAllocateInternalData` to ARKODE to enable stage-related
 data allocation before the first call to `ARKodeEvolve` (but after all other
 optional input routines have been called), to support users who measure memory
diff --git a/bindings/sundials4py/arkode/arkode_generated.hpp b/bindings/sundials4py/arkode/arkode_generated.hpp
index a494d031d4..ae68602b7e 100644
--- a/bindings/sundials4py/arkode/arkode_generated.hpp
+++ b/bindings/sundials4py/arkode/arkode_generated.hpp
@@ -500,6 +500,26 @@ m.def("ARKodeGetReturnFlagName", ARKodeGetReturnFlagName, nb::arg("flag"));
 m.def("ARKodeWriteParameters", ARKodeWriteParameters, nb::arg("arkode_mem"),
       nb::arg("fp"));
 
+m.def(
+  "ARKodeGetStageIndex",
+  [](void* arkode_mem) -> std::tuple<int, int, int>
+  {
+    auto ARKodeGetStageIndex_adapt_modifiable_immutable_to_return =
+      [](void* arkode_mem) -> std::tuple<int, int, int>
+    {
+      int stage_adapt_modifiable;
+      int max_stages_adapt_modifiable;
+
+      int r = ARKodeGetStageIndex(arkode_mem, &stage_adapt_modifiable,
+                                  &max_stages_adapt_modifiable);
+      return std::make_tuple(r, stage_adapt_modifiable,
+                             max_stages_adapt_modifiable);
+    };
+
+    return ARKodeGetStageIndex_adapt_modifiable_immutable_to_return(arkode_mem);
+  },
+  nb::arg("arkode_mem"));
+
 m.def(
   "ARKodeGetNumExpSteps",
   [](void* arkode_mem) -> std::tuple<int, long>
@@ -674,6 +694,40 @@ m.def(
   },
   nb::arg("arkode_mem"));
 
+m.def(
+  "ARKodeGetLastTime",
+  [](void* arkode_mem) -> std::tuple<int, sunrealtype>
+  {
+    auto ARKodeGetLastTime_adapt_modifiable_immutable_to_return =
+      [](void* arkode_mem) -> std::tuple<int, sunrealtype>
+    {
+      sunrealtype tn_adapt_modifiable;
+
+      int r = ARKodeGetLastTime(arkode_mem, &tn_adapt_modifiable);
+      return std::make_tuple(r, tn_adapt_modifiable);
+    };
+
+    return ARKodeGetLastTime_adapt_modifiable_immutable_to_return(arkode_mem);
+  },
+  nb::arg("arkode_mem"));
+
+m.def(
+  "ARKodeGetLastState",
+  [](void* arkode_mem) -> std::tuple<int, N_Vector>
+  {
+    auto ARKodeGetLastState_adapt_modifiable_immutable_to_return =
+      [](void* arkode_mem) -> std::tuple<int, N_Vector>
+    {
+      N_Vector state_adapt_modifiable;
+
+      int r = ARKodeGetLastState(arkode_mem, &state_adapt_modifiable);
+      return std::make_tuple(r, state_adapt_modifiable);
+    };
+
+    return ARKodeGetLastState_adapt_modifiable_immutable_to_return(arkode_mem);
+  },
+  nb::arg("arkode_mem"), "nb::rv_policy::reference", nb::rv_policy::reference);
+
 m.def(
   "ARKodeGetCurrentTime",
   [](void* arkode_mem) -> std::tuple<int, sunrealtype>
diff --git a/doc/arkode/guide/source/Usage/User_callable.rst b/doc/arkode/guide/source/Usage/User_callable.rst
index c9f25a21f8..59ddf75f69 100644
--- a/doc/arkode/guide/source/Usage/User_callable.rst
+++ b/doc/arkode/guide/source/Usage/User_callable.rst
@@ -3622,6 +3622,8 @@ Actual initial time step size used                     :c:func:`ARKodeGetActualI
 Step size used for the last successful step            :c:func:`ARKodeGetLastStep`
 Step size to be attempted on the next step             :c:func:`ARKodeGetCurrentStep`
 Integration direction, e.g., forward or backward       :c:func:`ARKodeGetStepDirection`
+Last saved time reached by the solver                  :c:func:`ARKodeGetLastTime`
+Last saved solution reached by the solver              :c:func:`ARKodeGetLastState`
 Current internal time reached by the solver            :c:func:`ARKodeGetCurrentTime`
 Current internal solution reached by the solver        :c:func:`ARKodeGetCurrentState`
 Current :math:`\gamma` value used by the solver        :c:func:`ARKodeGetCurrentGamma`
@@ -3641,6 +3643,7 @@ Estimated local truncation error vector                :c:func:`ARKodeGetEstLoca
 Number of constraint test failures                     :c:func:`ARKodeGetNumConstrFails`
 Retrieve a pointer for user data                       :c:func:`ARKodeGetUserData`
 Retrieve the accumulated temporal error estimate       :c:func:`ARKodeGetAccumulatedError`
+Current stage index, and total number of stages        :c:func:`ARKodeGetStageIndex`
 =====================================================  ============================================
 
 
@@ -3744,6 +3747,38 @@ Retrieve the accumulated temporal error estimate       :c:func:`ARKodeGetAccumul
    .. versionadded:: 6.2.0
 
 
+.. c:function:: int ARKodeGetLastTime(void* arkode_mem, sunrealtype* tn)
+
+   Returns the last saved time reached by the solver.
+
+   :param arkode_mem: pointer to the ARKODE memory block.
+   :param tn: last saved time reached.
+
+   :retval ARK_SUCCESS: the function exited successfully.
+   :retval ARK_MEM_NULL: ``arkode_mem`` was ``NULL``.
+
+   .. versionadded:: x.y.z
+
+
+.. c:function:: int ARKodeGetLastState(void *arkode_mem, N_Vector *yn)
+
+   Returns the last saved solution reached by the solver.
+
+   :param arkode_mem: pointer to the ARKODE memory block.
+   :param yn: last saved solution.
+
+   :retval ARK_SUCCESS: the function exited successfully.
+   :retval ARK_MEM_NULL: ``arkode_mem`` was ``NULL``.
+
+   .. note::
+
+      Users should exercise extreme caution when using this function,
+      as altering values of *yn* may lead to undesirable behavior, depending
+      on the particular use case and on when this routine is called.
+
+   .. versionadded:: x.y.z
+
+
 .. c:function:: int ARKodeGetCurrentTime(void* arkode_mem, sunrealtype* tcur)
 
    Returns the current internal time reached by the solver.
@@ -4117,6 +4152,21 @@ Retrieve the accumulated temporal error estimate       :c:func:`ARKodeGetAccumul
    .. versionadded:: 6.2.0
 
 
+.. c:function:: int ARKodeGetStageIndex(void* arkode_mem, int* stage, int *max_stages)
+
+   Returns the index of the current stage (0-based) and the total number of
+   stages in the method.
+
+   :param arkode_mem: pointer to the ARKODE memory block.
+   :param stage: pointer to storage for the current stage index.
+   :param max_stages: pointer to storage for the number of stages in the method.
+
+   :retval ARK_SUCCESS: the function exited successfully.
+   :retval ARK_MEM_NULL: ``arkode_mem`` was ``NULL``.
+
+   .. versionadded:: x.y.z
+
+
 
 
 
diff --git a/doc/shared/RecentChanges.rst b/doc/shared/RecentChanges.rst
index a5ba6594d8..da70a0ee86 100644
--- a/doc/shared/RecentChanges.rst
+++ b/doc/shared/RecentChanges.rst
@@ -7,6 +7,10 @@
 
 Multiple minor updates were made to the ARKODE package.  We removed an extraneous
 copy of the output vector when using ARKODE in ``ARK_ONE_STEP`` mode.  We added the
+function :c:func:`ARKodeGetStageIndex` that returns the index of the stage currently
+being processed, and the total number of stages in the method, for users who must
+compute auxiliary quantities in their IVP right-hand side functions during some
+stages and not others (e.g., in all but the first or last stage). We added the
 function :c:func:`ARKodeAllocateInternalData` to ARKODE to enable stage-related
 data allocation before the first call to :c:func:`ARKodeEvolve` (but after all other
 optional input routines have been called), to support users who measure memory
diff --git a/include/arkode/arkode.h b/include/arkode/arkode.h
index c5b2bb6495..2bb9dc7b39 100644
--- a/include/arkode/arkode.h
+++ b/include/arkode/arkode.h
@@ -382,6 +382,8 @@ SUNDIALS_EXPORT int ARKodePrintAllStats(void* arkode_mem, FILE* outfile,
                                         SUNOutputFormat fmt);
 SUNDIALS_EXPORT char* ARKodeGetReturnFlagName(long int flag);
 SUNDIALS_EXPORT int ARKodeWriteParameters(void* arkode_mem, FILE* fp);
+SUNDIALS_EXPORT int ARKodeGetStageIndex(void* arkode_mem, int* stage,
+                                        int* max_stages);
 
 /* Optional output functions (temporal adaptivity) */
 SUNDIALS_EXPORT int ARKodeGetNumExpSteps(void* arkode_mem, long int* expsteps);
@@ -404,6 +406,9 @@ SUNDIALS_EXPORT int ARKodeGetAccumulatedError(void* arkode_mem,
 /* Optional output functions (implicit solver) */
 SUNDIALS_EXPORT int ARKodeGetNumLinSolvSetups(void* arkode_mem,
                                               long int* nlinsetups);
+SUNDIALS_EXPORT int ARKodeGetLastTime(void* arkode_mem, sunrealtype* tn);
+SUNDIALS_EXPORT int ARKodeGetLastState(void* arkode_mem,
+                                       N_Vector* state); // nb::rv_policy::reference
 SUNDIALS_EXPORT int ARKodeGetCurrentTime(void* arkode_mem, sunrealtype* tcur);
 SUNDIALS_EXPORT int ARKodeGetCurrentState(void* arkode_mem,
                                           N_Vector* state); // nb::rv_policy::reference
diff --git a/src/arkode/arkode.c b/src/arkode/arkode.c
index 22c36a0afc..686f0c5faf 100644
--- a/src/arkode/arkode.c
+++ b/src/arkode/arkode.c
@@ -1580,6 +1580,7 @@ ARKodeMem arkCreate(SUNContext sunctx)
   ark_mem->step_getnumnonlinsolviters     = NULL;
   ark_mem->step_getnumnonlinsolvconvfails = NULL;
   ark_mem->step_getnonlinsolvstats        = NULL;
+  ark_mem->step_getstageindex             = NULL;
   ark_mem->step_setforcing                = NULL;
   ark_mem->step_mem                       = NULL;
   ark_mem->step_supports_adaptive         = SUNFALSE;
diff --git a/src/arkode/arkode_arkstep.c b/src/arkode/arkode_arkstep.c
index 641b06abc3..7095819f14 100644
--- a/src/arkode/arkode_arkstep.c
+++ b/src/arkode/arkode_arkstep.c
@@ -143,6 +143,7 @@ void* ARKStepCreate(ARKRhsFn fe, ARKRhsFn fi, sunrealtype t0, N_Vector y0,
   ark_mem->step_getnumnonlinsolvconvfails = arkStep_GetNumNonlinSolvConvFails;
   ark_mem->step_getnonlinsolvstats        = arkStep_GetNonlinSolvStats;
   ark_mem->step_setforcing                = arkStep_SetInnerForcing;
+  ark_mem->step_getstageindex             = arkStep_GetStageIndex;
   ark_mem->step_supports_adaptive         = SUNTRUE;
   ark_mem->step_supports_implicit         = SUNTRUE;
   ark_mem->step_supports_massmatrix       = SUNTRUE;
@@ -1711,6 +1712,9 @@ int arkStep_TakeStep_Z(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
     *nflagPtr = ARK_SUCCESS;
   }
 
+  /* initialize the current stage index */
+  step_mem->istage = 0;
+
   /* call nonlinear solver setup if it exists */
   if (step_mem->NLS)
   {
diff --git a/src/arkode/arkode_arkstep_impl.h b/src/arkode/arkode_arkstep_impl.h
index 48736e3e1c..9ae6783b1d 100644
--- a/src/arkode/arkode_arkstep_impl.h
+++ b/src/arkode/arkode_arkstep_impl.h
@@ -243,6 +243,7 @@ void arkStep_Free(ARKodeMem ark_mem);
 void arkStep_PrintMem(ARKodeMem ark_mem, FILE* outfile);
 int arkStep_SetInnerForcing(ARKodeMem ark_mem, sunrealtype tshift,
                             sunrealtype tscale, N_Vector* f, int nvecs);
+int arkStep_GetStageIndex(ARKodeMem ark_mem, int* stage, int* max_stages);
 
 /* Internal utility routines */
 int arkStep_AccessARKODEStepMem(void* arkode_mem, const char* fname,
diff --git a/src/arkode/arkode_arkstep_io.c b/src/arkode/arkode_arkstep_io.c
index 34e1af5d5c..7bbd6bd249 100644
--- a/src/arkode/arkode_arkstep_io.c
+++ b/src/arkode/arkode_arkstep_io.c
@@ -1298,6 +1298,26 @@ int arkStep_GetNonlinSolvStats(ARKodeMem ark_mem, long int* nniters,
   return (ARK_SUCCESS);
 }
 
+/*---------------------------------------------------------------
+  arkStep_GetStageIndex:
+
+  Returns the current stage index and number of stages
+  ---------------------------------------------------------------*/
+int arkStep_GetStageIndex(ARKodeMem ark_mem, int* stage, int* max_stages)
+{
+  ARKodeARKStepMem step_mem;
+  int retval;
+
+  /* access ARKodeARKStepMem structure */
+  retval = arkStep_AccessStepMem(ark_mem, __func__, &step_mem);
+  if (retval != ARK_SUCCESS) { return (retval); }
+
+  *stage      = step_mem->istage;
+  *max_stages = step_mem->stages;
+
+  return (ARK_SUCCESS);
+}
+
 /*---------------------------------------------------------------
   arkStep_PrintAllStats:
 
diff --git a/src/arkode/arkode_erkstep.c b/src/arkode/arkode_erkstep.c
index e47dce5120..965cc19e7e 100644
--- a/src/arkode/arkode_erkstep.c
+++ b/src/arkode/arkode_erkstep.c
@@ -109,6 +109,7 @@ void* ERKStepCreate(ARKRhsFn f, sunrealtype t0, N_Vector y0, SUNContext sunctx)
   ark_mem->step_getnumrhsevals        = erkStep_GetNumRhsEvals;
   ark_mem->step_getestlocalerrors     = erkStep_GetEstLocalErrors;
   ark_mem->step_setforcing            = erkStep_SetInnerForcing;
+  ark_mem->step_getstageindex         = erkStep_GetStageIndex;
   ark_mem->step_supports_adaptive     = SUNTRUE;
   ark_mem->step_supports_relaxation   = SUNTRUE;
   ark_mem->step_mem                   = (void*)step_mem;
@@ -364,6 +365,7 @@ void erkStep_PrintMem(ARKodeMem ark_mem, FILE* outfile)
   /* output integer quantities */
   fprintf(outfile, "ERKStep: q = %i\n", step_mem->q);
   fprintf(outfile, "ERKStep: p = %i\n", step_mem->p);
+  fprintf(outfile, "ERKStep: istage = %i\n", step_mem->istage);
   fprintf(outfile, "ERKStep: stages = %i\n", step_mem->stages);
 
   /* output long integer quantities */
@@ -770,6 +772,9 @@ int erkStep_TakeStep(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   cvals = step_mem->cvals;
   Xvecs = step_mem->Xvecs;
 
+  /* initialize the current stage index */
+  step_mem->istage = 0;
+
   SUNLogInfo(ARK_LOGGER, "begin-stages-list", "stage = 0, tcur = " SUN_FORMAT_G,
              ark_mem->tcur);
   SUNLogExtraDebugVec(ARK_LOGGER, "stage", ark_mem->yn, "z_0(:) =");
@@ -836,6 +841,9 @@ int erkStep_TakeStep(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
      the first stage RHS is just the full RHS from the start of the step */
   for (is = 1; is < step_mem->stages; is++)
   {
+    /* store current stage index */
+    step_mem->istage = is;
+
     /* Set current stage time(s) */
     ark_mem->tcur = ark_mem->tn + step_mem->B->c[is] * ark_mem->h;
 
diff --git a/src/arkode/arkode_erkstep_impl.h b/src/arkode/arkode_erkstep_impl.h
index 804d958169..641896bf31 100644
--- a/src/arkode/arkode_erkstep_impl.h
+++ b/src/arkode/arkode_erkstep_impl.h
@@ -58,6 +58,7 @@ typedef struct ARKodeERKStepMemRec
   N_Vector* F;          /* explicit RHS at each stage */
   int q;                /* method order               */
   int p;                /* embedding order            */
+  int istage;           /* current stage              */
   int stages;           /* number of stages           */
   ARKodeButcherTable B; /* ERK Butcher table          */
 
@@ -106,6 +107,7 @@ int erkStep_GetNumRhsEvals(ARKodeMem ark_mem, int partition_index,
 int erkStep_GetEstLocalErrors(ARKodeMem ark_mem, N_Vector ele);
 int erkStep_SetInnerForcing(ARKodeMem ark_mem, sunrealtype tshift,
                             sunrealtype tscale, N_Vector* f, int nvecs);
+int erkStep_GetStageIndex(ARKodeMem ark_mem, int* stage, int* max_stages);
 
 /* Internal utility routines */
 int erkStep_AccessARKODEStepMem(void* arkode_mem, const char* fname,
diff --git a/src/arkode/arkode_erkstep_io.c b/src/arkode/arkode_erkstep_io.c
index 7d422d862f..fc32863b1a 100644
--- a/src/arkode/arkode_erkstep_io.c
+++ b/src/arkode/arkode_erkstep_io.c
@@ -398,6 +398,26 @@ int erkStep_GetEstLocalErrors(ARKodeMem ark_mem, N_Vector ele)
   return (ARK_SUCCESS);
 }
 
+/*---------------------------------------------------------------
+  erkStep_GetStageIndex:
+
+  Returns the current stage index and number of stages
+  ---------------------------------------------------------------*/
+int erkStep_GetStageIndex(ARKodeMem ark_mem, int* stage, int* max_stages)
+{
+  ARKodeERKStepMem step_mem;
+  int retval;
+
+  /* access ARKodeARKStepMem structure */
+  retval = erkStep_AccessStepMem(ark_mem, __func__, &step_mem);
+  if (retval != ARK_SUCCESS) { return (retval); }
+
+  *stage      = step_mem->istage;
+  *max_stages = step_mem->stages;
+
+  return (ARK_SUCCESS);
+}
+
 /*---------------------------------------------------------------
   erkStep_PrintAllStats:
 
diff --git a/src/arkode/arkode_impl.h b/src/arkode/arkode_impl.h
index 13dbdebd3b..5d1be5e4c1 100644
--- a/src/arkode/arkode_impl.h
+++ b/src/arkode/arkode_impl.h
@@ -230,6 +230,8 @@ typedef int (*ARKTimestepSetUseCompensatedSums)(ARKodeMem ark_mem,
                                                 sunbooleantype onoff);
 typedef int (*ARKTimestepSetOptions)(ARKodeMem ark_mem, int* argidx, char* argv[],
                                      size_t offset, sunbooleantype* arg_used);
+typedef int (*ARKTimestepGetStageIndex)(ARKodeMem ark_mem, int* stage,
+                                        int* max_stages);
 
 /* time stepper interface functions -- temporal adaptivity */
 typedef int (*ARKTimestepGetEstLocalErrors)(ARKodeMem ark_mem, N_Vector ele);
@@ -423,6 +425,7 @@ struct ARKodeMemRec
   ARKTimestepSetStepDirection step_setstepdirection;
   ARKTimestepSetUseCompensatedSums step_setusecompensatedsums;
   ARKTimestepSetOptions step_setoptions;
+  ARKTimestepGetStageIndex step_getstageindex;
 
   /* Time stepper module -- temporal adaptivity */
   sunbooleantype step_supports_adaptive;
diff --git a/src/arkode/arkode_io.c b/src/arkode/arkode_io.c
index a9ab400166..c7c6808895 100644
--- a/src/arkode/arkode_io.c
+++ b/src/arkode/arkode_io.c
@@ -2569,6 +2569,46 @@ int ARKodeGetEstLocalErrors(void* arkode_mem, N_Vector ele)
   }
 }
 
+/*---------------------------------------------------------------
+  ARKodeGetLastTime:
+
+  Returns the last saved value of the independent variable
+  ---------------------------------------------------------------*/
+int ARKodeGetLastTime(void* arkode_mem, sunrealtype* tn)
+{
+  ARKodeMem ark_mem;
+  if (arkode_mem == NULL)
+  {
+    arkProcessError(NULL, ARK_MEM_NULL, __LINE__, __func__, __FILE__,
+                    MSG_ARK_NO_MEM);
+    return (ARK_MEM_NULL);
+  }
+  ark_mem = (ARKodeMem)arkode_mem;
+
+  *tn = ark_mem->tn;
+  return (ARK_SUCCESS);
+}
+
+/*---------------------------------------------------------------
+  ARKodeGetLastState:
+
+  Returns the last saved time step solution.
+  ---------------------------------------------------------------*/
+int ARKodeGetLastState(void* arkode_mem, N_Vector* yn)
+{
+  ARKodeMem ark_mem;
+  if (arkode_mem == NULL)
+  {
+    arkProcessError(NULL, ARK_MEM_NULL, __LINE__, __func__, __FILE__,
+                    MSG_ARK_NO_MEM);
+    return (ARK_MEM_NULL);
+  }
+  ark_mem = (ARKodeMem)arkode_mem;
+
+  *yn = ark_mem->yn;
+  return (ARK_SUCCESS);
+}
+
 /*---------------------------------------------------------------
   ARKodeGetCurrentTime:
 
@@ -3184,6 +3224,38 @@ int ARKodeGetUserData(void* arkode_mem, void** user_data)
   return (ARK_SUCCESS);
 }
 
+/*---------------------------------------------------------------
+  ARKodeGetStageIndex:
+
+  Returns the index of the current stage and the total number of
+  stages.  If this is not supplied by the time-stepping module
+  then it returns (0,1), indicating that it is currently in the
+  first of only a single stage.
+  ---------------------------------------------------------------*/
+int ARKodeGetStageIndex(void* arkode_mem, int* stage, int* max_stages)
+{
+  ARKodeMem ark_mem;
+  if (arkode_mem == NULL)
+  {
+    arkProcessError(NULL, ARK_MEM_NULL, __LINE__, __func__, __FILE__,
+                    MSG_ARK_NO_MEM);
+    return (ARK_MEM_NULL);
+  }
+  ark_mem = (ARKodeMem)arkode_mem;
+
+  /* Call stepper routine to compute the state (if provided) */
+  if (ark_mem->step_getstageindex)
+  {
+    return (ark_mem->step_getstageindex(ark_mem, stage, max_stages));
+  }
+  else
+  {
+    *stage      = 0;
+    *max_stages = 1;
+    return (ARK_SUCCESS);
+  }
+}
+
 /*-----------------------------------------------------------------
   ARKodePrintAllStats
 
diff --git a/src/arkode/arkode_lsrkstep.c b/src/arkode/arkode_lsrkstep.c
index 3ac9e7708b..98feb295b7 100644
--- a/src/arkode/arkode_lsrkstep.c
+++ b/src/arkode/arkode_lsrkstep.c
@@ -180,6 +180,7 @@ void* lsrkStep_Create_Commons(ARKRhsFn rhs, sunrealtype t0, N_Vector y0,
   ark_mem->step_setdefaults       = lsrkStep_SetDefaults;
   ark_mem->step_getnumrhsevals    = lsrkStep_GetNumRhsEvals;
   ark_mem->step_getestlocalerrors = lsrkStep_GetEstLocalErrors;
+  ark_mem->step_getstageindex     = lsrkStep_GetStageIndex;
   ark_mem->step_mem               = (void*)step_mem;
   ark_mem->step_supports_adaptive = SUNTRUE;
 
@@ -579,6 +580,10 @@ int lsrkStep_TakeStepRKC(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   sunrealtype* cvals = step_mem->cvals;
   N_Vector* Xvecs    = step_mem->Xvecs;
 
+  /* Initialize the current stage index */
+  step_mem->istage     = 0;
+  step_mem->req_stages = step_mem->stage_max_limit;
+
   /* Compute dominant eigenvalue and update stats */
   if (step_mem->dom_eig_update)
   {
@@ -710,6 +715,9 @@ int lsrkStep_TakeStepRKC(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   /* Evaluate stages j = 2,...,step_mem->req_stages */
   for (int j = 2; j <= step_mem->req_stages; j++)
   {
+    /* set stage index (0-based) */
+    step_mem->istage = j - 1;
+
     /* Evaluate RHS and store in tempv3 */
     ark_mem->tcur = ark_mem->tn + ark_mem->h * thjm1;
 
@@ -814,7 +822,8 @@ int lsrkStep_TakeStepRKC(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   SUNLogInfo(ARK_LOGGER, "begin-compute-embedding", "");
 
   /* final stage processing */
-  ark_mem->tcur = ark_mem->tn + ark_mem->h;
+  step_mem->istage = step_mem->req_stages;
+  ark_mem->tcur    = ark_mem->tn + ark_mem->h;
 
   /* apply user-supplied stage preprocessing function (if supplied) */
   if (ark_mem->PreProcessRHS != NULL)
@@ -919,6 +928,10 @@ int lsrkStep_TakeStepRKL(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   sunrealtype* cvals = step_mem->cvals;
   N_Vector* Xvecs    = step_mem->Xvecs;
 
+  /* Initialize the current stage index */
+  step_mem->istage     = 0;
+  step_mem->req_stages = step_mem->stage_max_limit;
+
   /* Compute dominant eigenvalue and update stats */
   if (step_mem->dom_eig_update)
   {
@@ -1040,6 +1053,9 @@ int lsrkStep_TakeStepRKL(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   /* Evaluate stages j = 2,...,step_mem->req_stages */
   for (int j = 2; j <= step_mem->req_stages; j++)
   {
+    /* set stage index (0-based) */
+    step_mem->istage = j - 1;
+
     /* Evaluate RHS and store in tempv3 */
     ark_mem->tcur = ark_mem->tn + ark_mem->h * cjm1;
 
@@ -1132,10 +1148,11 @@ int lsrkStep_TakeStepRKL(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
 
   SUNLogInfo(ARK_LOGGER, "end-stages-list", "status = success");
   SUNLogExtraDebugVec(ARK_LOGGER, "updated solution", ark_mem->ycur, "ycur(:) =");
+  SUNLogInfo(ARK_LOGGER, "begin-compute-embedding", "");
 
   /* final stage processing */
-  SUNLogInfo(ARK_LOGGER, "begin-compute-embedding", "");
-  ark_mem->tcur = ark_mem->tn + ark_mem->h;
+  step_mem->istage = step_mem->req_stages;
+  ark_mem->tcur    = ark_mem->tn + ark_mem->h;
 
   /* apply user-supplied stage preprocessing function (if supplied) */
   if (ark_mem->PreProcessRHS != NULL)
@@ -1230,6 +1247,9 @@ int lsrkStep_TakeStepSSPs2(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
   sunrealtype* cvals = step_mem->cvals;
   N_Vector* Xvecs    = step_mem->Xvecs;
 
+  /* Initialize the current stage index */
+  step_mem->istage = 0;
+
   /* Initialize method coefficients */
   const sunrealtype rs      = (sunrealtype)step_mem->req_stages;
   const sunrealtype sm1inv  = ONE / (rs - ONE);
@@ -1316,6 +1336,9 @@ int lsrkStep_TakeStepSSPs2(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
   /* Evaluate stages j = 2,...,step_mem->req_stages - 1 */
   for (int j = 2; j < step_mem->req_stages; j++)
   {
+    /* set stage index (0-based) */
+    step_mem->istage = j - 1;
+
     /* Complete previous stage by evaluating RHS and storing it in tempv2 */
     ark_mem->tcur = ark_mem->tn + (j - 1) * hsm1inv;
 
@@ -1371,7 +1394,8 @@ int lsrkStep_TakeStepSSPs2(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
   }
 
   /* Complete the next-to-last stage by evaluating the RHS and storing it in tempv2 */
-  ark_mem->tcur = ark_mem->tn + ark_mem->h;
+  step_mem->istage = step_mem->req_stages - 1;
+  ark_mem->tcur    = ark_mem->tn + ark_mem->h;
   if (ark_mem->PreProcessRHS != NULL)
   {
     retval = ark_mem->PreProcessRHS(ark_mem->tcur, ark_mem->ycur,
@@ -1475,6 +1499,9 @@ int lsrkStep_TakeStepSSPs3(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
   sunrealtype* cvals = step_mem->cvals;
   N_Vector* Xvecs    = step_mem->Xvecs;
 
+  /* Initialize the current stage index */
+  step_mem->istage = 0;
+
   /* Initialize method coefficients */
   const sunrealtype rs     = (sunrealtype)step_mem->req_stages;
   const sunrealtype rn     = SUNRsqrt(rs);
@@ -1547,6 +1574,9 @@ int lsrkStep_TakeStepSSPs3(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
   /* Evaluate first stage group */
   for (int j = 2; j <= ((in - 1) * (in - 2) / 2); j++)
   {
+    /* set stage index (0-based) */
+    step_mem->istage = j - 1;
+
     /* Complete previous stage by evaluating RHS and storing it in tempv3 */
     ark_mem->tcur = ark_mem->tn + (j - 1) * hrat;
 
@@ -1608,6 +1638,9 @@ int lsrkStep_TakeStepSSPs3(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
   /* Evaluate second stage group */
   for (int j = ((in - 1) * (in - 2) / 2 + 1); j <= (in * (in + 1) / 2 - 1); j++)
   {
+    /* set stage index (0-based) */
+    step_mem->istage = j - 1;
+
     /* Complete previous stage by evaluating RHS and storing it in tempv3 */
     ark_mem->tcur = ark_mem->tn + (j - 1) * hrat;
 
@@ -1664,7 +1697,8 @@ int lsrkStep_TakeStepSSPs3(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
   }
 
   /* Complete the last stage from the second stage group */
-  ark_mem->tcur = ark_mem->tn + hrat * (rn * (rn + ONE) / TWO - ONE);
+  step_mem->istage = (in * (in + 1) / 2 - 1);
+  ark_mem->tcur    = ark_mem->tn + hrat * (rn * (rn + ONE) / TWO - ONE);
 
   /* apply user-supplied stage preprocessing function (if supplied) */
   if (ark_mem->PreProcessRHS != NULL)
@@ -1731,6 +1765,9 @@ int lsrkStep_TakeStepSSPs3(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
   /* Evaluate final stage group */
   for (int j = (in * (in + 1) / 2 + 1); j <= step_mem->req_stages; j++)
   {
+    /* set stage index (0-based) */
+    step_mem->istage = j - 1;
+
     /* Complete the previous stage */
     ark_mem->tcur = ark_mem->tn + (j - in - 1) * hrat;
 
@@ -1848,6 +1885,9 @@ int lsrkStep_TakeStepSSP43(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
   sunrealtype* cvals = step_mem->cvals;
   N_Vector* Xvecs    = step_mem->Xvecs;
 
+  /* Initialize the current stage index */
+  step_mem->istage = 0;
+
   /* Initialize method coefficients */
   const sunrealtype rs     = SUN_RCONST(4.0);
   const sunrealtype hp5    = ark_mem->h * SUN_RCONST(0.5);
@@ -1915,6 +1955,9 @@ int lsrkStep_TakeStepSSP43(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
     }
   }
 
+  /* update stage index */
+  step_mem->istage = 1;
+
   /* apply user-supplied stage preprocessing function (if supplied) */
   if (ark_mem->PreProcessRHS != NULL)
   {
@@ -1965,6 +2008,9 @@ int lsrkStep_TakeStepSSP43(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
     }
   }
 
+  /* update stage index */
+  step_mem->istage = 2;
+
   /* Evaluate stage RHS */
 
   /* apply user-supplied stage preprocessing function (if supplied) */
@@ -2028,6 +2074,9 @@ int lsrkStep_TakeStepSSP43(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr
     }
   }
 
+  /* update stage index */
+  step_mem->istage = 3;
+
   /* Evaluate stage RHS */
 
   /* apply user-supplied stage preprocessing function (if supplied) */
@@ -2120,6 +2169,9 @@ int lsrkStep_TakeStepSSP104(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPt
   sunrealtype* cvals = step_mem->cvals;
   N_Vector* Xvecs    = step_mem->Xvecs;
 
+  /* Initialize the current stage index */
+  step_mem->istage = 0;
+
   /* Initialize method coefficients */
   const sunrealtype hsixth = ark_mem->h / SIX;
   const sunrealtype hfifth = ark_mem->h / FIVE;
@@ -2191,6 +2243,9 @@ int lsrkStep_TakeStepSSP104(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPt
   /* Evaluate stages j = 2,...,4 */
   for (int j = 2; j <= 5; j++)
   {
+    /* set stage index (0-based) */
+    step_mem->istage = j - 1;
+
     /* Complete previous stage by evaluating RHS and storing in tempv3 */
     ark_mem->tcur = ark_mem->tn + (j - 1) * hsixth;
 
@@ -2277,6 +2332,9 @@ int lsrkStep_TakeStepSSP104(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPt
   /* Evaluate stages j = 6,...,9 */
   for (int j = 6; j <= 9; j++)
   {
+    /* set stage index (0-based) */
+    step_mem->istage = j - 1;
+
     /* Complete previous stage by evaluating RHS and storing in tempv3 */
     ark_mem->tcur = ark_mem->tn + (j - 4) * hsixth;
 
@@ -2337,7 +2395,10 @@ int lsrkStep_TakeStepSSP104(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPt
     }
   }
 
-  /* Complete the 9th stage by evaluating RHS and storing in tempv3 */
+  /* set stage index (0-based) */
+  step_mem->istage = 9;
+
+  /* Complete the last stage by evaluating RHS and storing in tempv3 */
   ark_mem->tcur = ark_mem->tn + ark_mem->h;
 
   /* apply user-supplied stage preprocessing function (if supplied) */
@@ -2470,18 +2531,16 @@ void lsrkStep_PrintMem(ARKodeMem ark_mem, FILE* outfile)
 
   fprintf(outfile, "LSRKStep: q                   = %i\n", step_mem->q);
   fprintf(outfile, "LSRKStep: p                   = %i\n", step_mem->p);
+  fprintf(outfile, "LSRKStep: istage              = %i\n", step_mem->istage);
+  fprintf(outfile, "LSRKStep: req_stages          = %i\n", step_mem->req_stages);
 
   if (step_mem->is_SSP)
   {
-    fprintf(outfile, "LSRKStep: req_stages          = %i\n",
-            step_mem->req_stages);
     fprintf(outfile, "LSRKStep: nfe                 = %li\n", step_mem->nfe);
   }
   else if (!step_mem->is_SSP)
   {
     /* output integer quantities */
-    fprintf(outfile, "LSRKStep: req_stages            = %i\n",
-            step_mem->req_stages);
     fprintf(outfile, "LSRKStep: dom_eig_nst           = %li\n",
             step_mem->dom_eig_nst);
     fprintf(outfile, "LSRKStep: stage_max             = %i\n",
diff --git a/src/arkode/arkode_lsrkstep_impl.h b/src/arkode/arkode_lsrkstep_impl.h
index 7dde8529bc..e6aeb4eee4 100644
--- a/src/arkode/arkode_lsrkstep_impl.h
+++ b/src/arkode/arkode_lsrkstep_impl.h
@@ -139,7 +139,8 @@ typedef struct ARKodeLSRKStepMemRec
   int q; /* method order               */
   int p; /* embedding order            */
 
-  int req_stages; /* number of requested stages   */
+  int istage;     /* current stage            */
+  int req_stages; /* number of stages in step */
 
   ARKODE_LSRKMethodType LSRKmethod;
 
@@ -209,6 +210,7 @@ void lsrkStep_PrintMem(ARKodeMem ark_mem, FILE* outfile);
 int lsrkStep_GetNumRhsEvals(ARKodeMem ark_mem, int partition_index,
                             long int* rhs_evals);
 int lsrkStep_GetEstLocalErrors(ARKodeMem ark_mem, N_Vector ele);
+int lsrkStep_GetStageIndex(ARKodeMem ark_mem, int* stage, int* max_stages);
 
 /* Internal utility routines */
 int lsrkStep_AccessARKODEStepMem(void* arkode_mem, const char* fname,
diff --git a/src/arkode/arkode_lsrkstep_io.c b/src/arkode/arkode_lsrkstep_io.c
index a6cf3c61cf..f9ebd232a6 100644
--- a/src/arkode/arkode_lsrkstep_io.c
+++ b/src/arkode/arkode_lsrkstep_io.c
@@ -772,6 +772,26 @@ int lsrkStep_SetDefaults(ARKodeMem ark_mem)
   return ARK_SUCCESS;
 }
 
+/*---------------------------------------------------------------
+  lsrkStep_GetStageIndex:
+
+  Returns the current stage index and number of stages
+  ---------------------------------------------------------------*/
+int lsrkStep_GetStageIndex(ARKodeMem ark_mem, int* stage, int* max_stages)
+{
+  ARKodeLSRKStepMem step_mem;
+  int retval;
+
+  /* access ARKodeLSRKStepMem structure */
+  retval = lsrkStep_AccessStepMem(ark_mem, __func__, &step_mem);
+  if (retval != ARK_SUCCESS) { return (retval); }
+
+  *stage      = step_mem->istage;
+  *max_stages = step_mem->req_stages;
+
+  return (ARK_SUCCESS);
+}
+
 /*---------------------------------------------------------------
   lsrkStep_PrintAllStats:
 
diff --git a/src/arkode/arkode_mristep.c b/src/arkode/arkode_mristep.c
index 80657971c7..bc8257af16 100644
--- a/src/arkode/arkode_mristep.c
+++ b/src/arkode/arkode_mristep.c
@@ -140,6 +140,7 @@ void* MRIStepCreate(ARKRhsFn fse, ARKRhsFn fsi, sunrealtype t0, N_Vector y0,
   ark_mem->step_getnumnonlinsolvconvfails = mriStep_GetNumNonlinSolvConvFails;
   ark_mem->step_getnonlinsolvstats        = mriStep_GetNonlinSolvStats;
   ark_mem->step_setforcing                = mriStep_SetInnerForcing;
+  ark_mem->step_getstageindex             = mriStep_GetStageIndex;
   ark_mem->step_supports_adaptive         = SUNTRUE;
   ark_mem->step_supports_implicit         = SUNTRUE;
   ark_mem->step_mem                       = (void*)step_mem;
@@ -1837,6 +1838,9 @@ int mriStep_TakeStepMRIGARK(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPt
   do_embedding = !ark_mem->fixedstep ||
                  (ark_mem->AccumErrorType != ARK_ACCUMERROR_NONE);
 
+  /* initialize the current stage index */
+  step_mem->istage = 0;
+
   /* if MRI adaptivity is enabled: reset fast accumulated error,
      and send appropriate control parameter to the fast integrator */
   adapt_type     = SUNAdaptController_GetType(ark_mem->hadapt_mem->hcontroller);
@@ -1948,6 +1952,9 @@ int mriStep_TakeStepMRIGARK(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPt
   /* Loop over remaining internal stages */
   for (is = 1; is < step_mem->stages - 1; is++)
   {
+    /* Set current stage index (0-based) */
+    step_mem->istage = is;
+
     /* Set relevant stage times (including desired stage time for implicit solves) */
     t0 = ark_mem->tn + step_mem->MRIC->c[is - 1] * ark_mem->h;
     tf = ark_mem->tcur = ark_mem->tn + step_mem->MRIC->c[is] * ark_mem->h;
@@ -2141,7 +2148,8 @@ int mriStep_TakeStepMRIGARK(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPt
   /* perform embedded stage (if needed) */
   if (do_embedding)
   {
-    is = step_mem->stages;
+    /* Set current stage index */
+    step_mem->istage = is = step_mem->stages;
 
     /* Copy ark_mem->ycur into ark_mem->tempv4, since it serves as the initial condition
        for both this embedding stage, and the subsequent final stage. */
@@ -2219,7 +2227,8 @@ int mriStep_TakeStepMRIGARK(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPt
 
   /* Compute final stage (for evolved solution), along with error estimate */
   {
-    is = step_mem->stages - 1;
+    /* Set current stage index */
+    step_mem->istage = is = step_mem->stages - 1;
 
     /* Set relevant stage times (including desired stage time for implicit solves) */
     t0 = ark_mem->tn + step_mem->MRIC->c[is - 1] * ark_mem->h;
@@ -2389,6 +2398,9 @@ int mriStep_TakeStepMRISR(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   ytilde = ark_mem->tempv4;
   ytemp  = ark_mem->tempv2;
 
+  /* initialize the current stage index */
+  step_mem->istage = 0;
+
   /* if MRI adaptivity is enabled: reset fast accumulated error,
      and send appropriate control parameter to the fast integrator */
   adapt_type     = SUNAdaptController_GetType(ark_mem->hadapt_mem->hcontroller);
@@ -2501,6 +2513,9 @@ int mriStep_TakeStepMRISR(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   /* Loop over stages */
   for (stage = 1; stage < max_stages; stage++)
   {
+    /* Set current stage index */
+    step_mem->istage = stage;
+
     /* Determine if this is an "embedding" or "solution" stage */
     solution  = (stage == step_mem->stages - 1);
     embedding = (stage == step_mem->stages);
@@ -2872,6 +2887,9 @@ int mriStep_TakeStepMERK(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   /* initial time for step */
   t0 = ark_mem->tn;
 
+  /* initialize the current stage index */
+  step_mem->istage = 0;
+
   /* if MRI adaptivity is enabled: reset fast accumulated error,
      and send appropriate control parameter to the fast integrator */
   adapt_type     = SUNAdaptController_GetType(ark_mem->hadapt_mem->hcontroller);
@@ -2990,7 +3008,7 @@ int mriStep_TakeStepMERK(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
     {
       /* Get stage index from group; skip to the next group if
          we've reached the end of this one */
-      stage = step_mem->MRIC->group[ig][is];
+      step_mem->istage = stage = step_mem->MRIC->group[ig][is];
       if (stage < 0) { break; }
       nextstage = -1;
       if (stage < step_mem->stages)
diff --git a/src/arkode/arkode_mristep_impl.h b/src/arkode/arkode_mristep_impl.h
index 66d76e08db..61a5f163b6 100644
--- a/src/arkode/arkode_mristep_impl.h
+++ b/src/arkode/arkode_mristep_impl.h
@@ -269,6 +269,7 @@ int mriStep_GetNumNonlinSolvIters(ARKodeMem ark_mem, long int* nniters);
 int mriStep_GetNumNonlinSolvConvFails(ARKodeMem ark_mem, long int* nnfails);
 int mriStep_GetNonlinSolvStats(ARKodeMem ark_mem, long int* nniters,
                                long int* nnfails);
+int mriStep_GetStageIndex(ARKodeMem ark_mem, int* stage, int* max_stages);
 int mriStep_PrintAllStats(ARKodeMem ark_mem, FILE* outfile, SUNOutputFormat fmt);
 int mriStep_WriteParameters(ARKodeMem ark_mem, FILE* fp);
 int mriStep_Reset(ARKodeMem ark_mem, sunrealtype tR, N_Vector yR);
diff --git a/src/arkode/arkode_mristep_io.c b/src/arkode/arkode_mristep_io.c
index 306e791f24..c18a48eeb6 100644
--- a/src/arkode/arkode_mristep_io.c
+++ b/src/arkode/arkode_mristep_io.c
@@ -828,6 +828,26 @@ int mriStep_GetNonlinSolvStats(ARKodeMem ark_mem, long int* nniters,
   return (ARK_SUCCESS);
 }
 
+/*---------------------------------------------------------------
+  mriStep_GetStageIndex:
+
+  Returns the current stage index and number of stages
+  ---------------------------------------------------------------*/
+int mriStep_GetStageIndex(ARKodeMem ark_mem, int* stage, int* max_stages)
+{
+  ARKodeMRIStepMem step_mem;
+  int retval;
+
+  /* access ARKodeMRIStepMem structure */
+  retval = mriStep_AccessStepMem(ark_mem, __func__, &step_mem);
+  if (retval != ARK_SUCCESS) { return (retval); }
+
+  *stage      = step_mem->istage;
+  *max_stages = step_mem->stages;
+
+  return (ARK_SUCCESS);
+}
+
 /*---------------------------------------------------------------
   mriStep_PrintAllStats:
 
diff --git a/src/arkode/arkode_splittingstep.c b/src/arkode/arkode_splittingstep.c
index 789cb59971..124e5b5852 100644
--- a/src/arkode/arkode_splittingstep.c
+++ b/src/arkode/arkode_splittingstep.c
@@ -312,6 +312,7 @@ static int splittingStep_TakeStep(ARKodeMem ark_mem, sunrealtype* dsmPtr,
   SUNLogInfo(ARK_LOGGER, "begin-sequential-methods-list",
              "sequential method = 0");
 
+  step_mem->istage = 0;
   retval = splittingStep_SequentialMethod(ark_mem, step_mem, 0, ark_mem->ycur);
   SUNLogExtraDebugVec(ARK_LOGGER, "sequential state", ark_mem->ycur,
                       "y_seq(:) =");
@@ -331,6 +332,7 @@ static int splittingStep_TakeStep(ARKodeMem ark_mem, sunrealtype* dsmPtr,
 
   for (int i = 1; i < coefficients->sequential_methods; i++)
   {
+    step_mem->istage = i;
     SUNLogInfo(ARK_LOGGER, "begin-sequential-methods-list",
                "sequential method = %i", i);
 
@@ -423,6 +425,7 @@ static void splittingStep_PrintMem(ARKodeMem ark_mem, FILE* outfile)
   if (retval != ARK_SUCCESS) { return; }
 
   /* output integer quantities */
+  fprintf(outfile, "SplittingStep: istage = %i\n", step_mem->istage);
   fprintf(outfile, "SplittingStep: partitions = %i\n", step_mem->partitions);
   fprintf(outfile, "SplittingStep: order = %i\n", step_mem->order);
 
@@ -455,6 +458,31 @@ static int splittingStep_SetOrder(ARKodeMem ark_mem, int order)
   return ARK_SUCCESS;
 }
 
+/*---------------------------------------------------------------
+  Returns the current stage index and number of stages
+  ---------------------------------------------------------------*/
+static int splittingStep_GetStageIndex(ARKodeMem ark_mem, int* istage,
+                                       int* num_stages)
+{
+  ARKodeSplittingStepMem step_mem;
+  int retval = splittingStep_AccessStepMem(ark_mem, __func__, &step_mem);
+  if (retval != ARK_SUCCESS) { return (retval); }
+
+  /* if coefficients structure is not yet available, return defaults */
+  if (step_mem->coefficients == NULL)
+  {
+    *istage     = 0;
+    *num_stages = 1;
+  }
+  else
+  {
+    *istage     = step_mem->istage;
+    *num_stages = step_mem->coefficients->sequential_methods;
+  }
+
+  return (ARK_SUCCESS);
+}
+
 /*------------------------------------------------------------------------------
   Routine to set SplittingStep options
   ----------------------------------------------------------------------------*/
@@ -661,6 +689,7 @@ void* SplittingStepCreate(SUNStepper* steppers, int partitions, sunrealtype t0,
   ark_mem->step_setoptions      = splittingStep_SetOptions;
   ark_mem->step_setdefaults     = splittingStep_SetDefaults;
   ark_mem->step_setorder        = splittingStep_SetOrder;
+  ark_mem->step_getstageindex   = splittingStep_GetStageIndex;
   ark_mem->step_mem             = (void*)step_mem;
 
   /* Set default values for ARKStep optional inputs */
diff --git a/src/arkode/arkode_splittingstep_impl.h b/src/arkode/arkode_splittingstep_impl.h
index 6dff626768..51438d27d3 100644
--- a/src/arkode/arkode_splittingstep_impl.h
+++ b/src/arkode/arkode_splittingstep_impl.h
@@ -28,6 +28,7 @@ typedef struct ARKodeSplittingStepMemRec
   SplittingStepCoefficients coefficients;
   long int* n_stepper_evolves;
 
+  int istage;
   int partitions;
   int order;
 }* ARKodeSplittingStepMem;
diff --git a/src/arkode/arkode_sprkstep.c b/src/arkode/arkode_sprkstep.c
index 2cfe794a6d..3ffb1d8bb5 100644
--- a/src/arkode/arkode_sprkstep.c
+++ b/src/arkode/arkode_sprkstep.c
@@ -123,6 +123,7 @@ void* SPRKStepCreate(ARKRhsFn f1, ARKRhsFn f2, sunrealtype t0, N_Vector y0,
   ark_mem->step_setdefaults           = sprkStep_SetDefaults;
   ark_mem->step_setorder              = sprkStep_SetOrder;
   ark_mem->step_getnumrhsevals        = sprkStep_GetNumRhsEvals;
+  ark_mem->step_getstageindex         = sprkStep_GetStageIndex;
   ark_mem->step_mem                   = (void*)step_mem;
 
   /* Set default values for optional inputs */
diff --git a/src/arkode/arkode_sprkstep_impl.h b/src/arkode/arkode_sprkstep_impl.h
index e858659a29..9a5e6a291b 100644
--- a/src/arkode/arkode_sprkstep_impl.h
+++ b/src/arkode/arkode_sprkstep_impl.h
@@ -91,6 +91,7 @@ void sprkStep_Free(ARKodeMem ark_mem);
 void sprkStep_PrintMem(ARKodeMem ark_mem, FILE* outfile);
 int sprkStep_GetNumRhsEvals(ARKodeMem ark_mem, int partition_index,
                             long int* rhs_evals);
+int sprkStep_GetStageIndex(ARKodeMem ark_mem, int* stage, int* max_stages);
 
 /* Internal utility routines */
 int sprkStep_AccessARKODEStepMem(void* arkode_mem, const char* fname,
diff --git a/src/arkode/arkode_sprkstep_io.c b/src/arkode/arkode_sprkstep_io.c
index 3d335c5d9b..1d48aaa57d 100644
--- a/src/arkode/arkode_sprkstep_io.c
+++ b/src/arkode/arkode_sprkstep_io.c
@@ -275,6 +275,35 @@ int sprkStep_SetOrder(ARKodeMem ark_mem, int ord)
   return (ARK_SUCCESS);
 }
 
+/*---------------------------------------------------------------
+  sprkStep_GetStageIndex:
+
+  Returns the current stage index and number of stages
+  ---------------------------------------------------------------*/
+int sprkStep_GetStageIndex(ARKodeMem ark_mem, int* stage, int* max_stages)
+{
+  ARKodeSPRKStepMem step_mem;
+  int retval;
+
+  /* access ARKodeSPRKStepMem structure */
+  retval = sprkStep_AccessStepMem(ark_mem, __func__, &step_mem);
+  if (retval != ARK_SUCCESS) { return (retval); }
+
+  /* if table is not yet set, return defaults */
+  if (step_mem->method == NULL)
+  {
+    *stage      = 0;
+    *max_stages = 1;
+  }
+  else
+  {
+    *stage      = step_mem->istage;
+    *max_stages = step_mem->method->stages;
+  }
+
+  return (ARK_SUCCESS);
+}
+
 /*---------------------------------------------------------------
   sprkStep_PrintAllStats:
 
diff --git a/src/arkode/fmod_int32/farkode_mod.c b/src/arkode/fmod_int32/farkode_mod.c
index 395c7ce83a..b498eac483 100644
--- a/src/arkode/fmod_int32/farkode_mod.c
+++ b/src/arkode/fmod_int32/farkode_mod.c
@@ -1561,6 +1561,22 @@ SWIGEXPORT int _wrap_FARKodeWriteParameters(void *farg1, void *farg2) {
 }
 
 
+SWIGEXPORT int _wrap_FARKodeGetStageIndex(void *farg1, int *farg2, int *farg3) {
+  int fresult ;
+  void *arg1 = (void *) 0 ;
+  int *arg2 = (int *) 0 ;
+  int *arg3 = (int *) 0 ;
+  int result;
+  
+  arg1 = (void *)(farg1);
+  arg2 = (int *)(farg2);
+  arg3 = (int *)(farg3);
+  result = (int)ARKodeGetStageIndex(arg1,arg2,arg3);
+  fresult = (int)(result);
+  return fresult;
+}
+
+
 SWIGEXPORT int _wrap_FARKodeGetNumExpSteps(void *farg1, long *farg2) {
   int fresult ;
   void *arg1 = (void *) 0 ;
@@ -1709,6 +1725,34 @@ SWIGEXPORT int _wrap_FARKodeGetNumLinSolvSetups(void *farg1, long *farg2) {
 }
 
 
+SWIGEXPORT int _wrap_FARKodeGetLastTime(void *farg1, double *farg2) {
+  int fresult ;
+  void *arg1 = (void *) 0 ;
+  sunrealtype *arg2 = (sunrealtype *) 0 ;
+  int result;
+  
+  arg1 = (void *)(farg1);
+  arg2 = (sunrealtype *)(farg2);
+  result = (int)ARKodeGetLastTime(arg1,arg2);
+  fresult = (int)(result);
+  return fresult;
+}
+
+
+SWIGEXPORT int _wrap_FARKodeGetLastState(void *farg1, void *farg2) {
+  int fresult ;
+  void *arg1 = (void *) 0 ;
+  N_Vector *arg2 = (N_Vector *) 0 ;
+  int result;
+  
+  arg1 = (void *)(farg1);
+  arg2 = (N_Vector *)(farg2);
+  result = (int)ARKodeGetLastState(arg1,arg2);
+  fresult = (int)(result);
+  return fresult;
+}
+
+
 SWIGEXPORT int _wrap_FARKodeGetCurrentTime(void *farg1, double *farg2) {
   int fresult ;
   void *arg1 = (void *) 0 ;
diff --git a/src/arkode/fmod_int32/farkode_mod.f90 b/src/arkode/fmod_int32/farkode_mod.f90
index ce0e0296eb..ab899d62f3 100644
--- a/src/arkode/fmod_int32/farkode_mod.f90
+++ b/src/arkode/fmod_int32/farkode_mod.f90
@@ -213,6 +213,7 @@ module farkode_mod
  public :: FARKodePrintAllStats
  public :: FARKodeGetReturnFlagName
  public :: FARKodeWriteParameters
+ public :: FARKodeGetStageIndex
  public :: FARKodeGetNumExpSteps
  public :: FARKodeGetNumAccSteps
  public :: FARKodeGetNumErrTestFails
@@ -223,6 +224,8 @@ module farkode_mod
  public :: FARKodeGetStepStats
  public :: FARKodeGetAccumulatedError
  public :: FARKodeGetNumLinSolvSetups
+ public :: FARKodeGetLastTime
+ public :: FARKodeGetLastState
  public :: FARKodeGetCurrentTime
  public :: FARKodeGetCurrentState
  public :: FARKodeGetCurrentGamma
@@ -1299,6 +1302,16 @@ function swigc_FARKodeWriteParameters(farg1, farg2) &
 integer(C_INT) :: fresult
 end function
 
+function swigc_FARKodeGetStageIndex(farg1, farg2, farg3) &
+bind(C, name="_wrap_FARKodeGetStageIndex") &
+result(fresult)
+use, intrinsic :: ISO_C_BINDING
+type(C_PTR), value :: farg1
+type(C_PTR), value :: farg2
+type(C_PTR), value :: farg3
+integer(C_INT) :: fresult
+end function
+
 function swigc_FARKodeGetNumExpSteps(farg1, farg2) &
 bind(C, name="_wrap_FARKodeGetNumExpSteps") &
 result(fresult)
@@ -1393,6 +1406,24 @@ function swigc_FARKodeGetNumLinSolvSetups(farg1, farg2) &
 integer(C_INT) :: fresult
 end function
 
+function swigc_FARKodeGetLastTime(farg1, farg2) &
+bind(C, name="_wrap_FARKodeGetLastTime") &
+result(fresult)
+use, intrinsic :: ISO_C_BINDING
+type(C_PTR), value :: farg1
+type(C_PTR), value :: farg2
+integer(C_INT) :: fresult
+end function
+
+function swigc_FARKodeGetLastState(farg1, farg2) &
+bind(C, name="_wrap_FARKodeGetLastState") &
+result(fresult)
+use, intrinsic :: ISO_C_BINDING
+type(C_PTR), value :: farg1
+type(C_PTR), value :: farg2
+integer(C_INT) :: fresult
+end function
+
 function swigc_FARKodeGetCurrentTime(farg1, farg2) &
 bind(C, name="_wrap_FARKodeGetCurrentTime") &
 result(fresult)
@@ -4014,6 +4045,25 @@ function FARKodeWriteParameters(arkode_mem, fp) &
 swig_result = fresult
 end function
 
+function FARKodeGetStageIndex(arkode_mem, stage, max_stages) &
+result(swig_result)
+use, intrinsic :: ISO_C_BINDING
+integer(C_INT) :: swig_result
+type(C_PTR) :: arkode_mem
+integer(C_INT), dimension(*), target, intent(inout) :: stage
+integer(C_INT), dimension(*), target, intent(inout) :: max_stages
+integer(C_INT) :: fresult 
+type(C_PTR) :: farg1 
+type(C_PTR) :: farg2 
+type(C_PTR) :: farg3 
+
+farg1 = arkode_mem
+farg2 = c_loc(stage(1))
+farg3 = c_loc(max_stages(1))
+fresult = swigc_FARKodeGetStageIndex(farg1, farg2, farg3)
+swig_result = fresult
+end function
+
 function FARKodeGetNumExpSteps(arkode_mem, expsteps) &
 result(swig_result)
 use, intrinsic :: ISO_C_BINDING
@@ -4186,6 +4236,38 @@ function FARKodeGetNumLinSolvSetups(arkode_mem, nlinsetups) &
 swig_result = fresult
 end function
 
+function FARKodeGetLastTime(arkode_mem, tn) &
+result(swig_result)
+use, intrinsic :: ISO_C_BINDING
+integer(C_INT) :: swig_result
+type(C_PTR) :: arkode_mem
+real(C_DOUBLE), dimension(*), target, intent(inout) :: tn
+integer(C_INT) :: fresult 
+type(C_PTR) :: farg1 
+type(C_PTR) :: farg2 
+
+farg1 = arkode_mem
+farg2 = c_loc(tn(1))
+fresult = swigc_FARKodeGetLastTime(farg1, farg2)
+swig_result = fresult
+end function
+
+function FARKodeGetLastState(arkode_mem, state) &
+result(swig_result)
+use, intrinsic :: ISO_C_BINDING
+integer(C_INT) :: swig_result
+type(C_PTR) :: arkode_mem
+type(C_PTR) :: state
+integer(C_INT) :: fresult 
+type(C_PTR) :: farg1 
+type(C_PTR) :: farg2 
+
+farg1 = arkode_mem
+farg2 = state
+fresult = swigc_FARKodeGetLastState(farg1, farg2)
+swig_result = fresult
+end function
+
 function FARKodeGetCurrentTime(arkode_mem, tcur) &
 result(swig_result)
 use, intrinsic :: ISO_C_BINDING
diff --git a/src/arkode/fmod_int64/farkode_mod.c b/src/arkode/fmod_int64/farkode_mod.c
index faaf3eefd7..e6774f8b0d 100644
--- a/src/arkode/fmod_int64/farkode_mod.c
+++ b/src/arkode/fmod_int64/farkode_mod.c
@@ -1561,6 +1561,22 @@ SWIGEXPORT int _wrap_FARKodeWriteParameters(void *farg1, void *farg2) {
 }
 
 
+SWIGEXPORT int _wrap_FARKodeGetStageIndex(void *farg1, int *farg2, int *farg3) {
+  int fresult ;
+  void *arg1 = (void *) 0 ;
+  int *arg2 = (int *) 0 ;
+  int *arg3 = (int *) 0 ;
+  int result;
+  
+  arg1 = (void *)(farg1);
+  arg2 = (int *)(farg2);
+  arg3 = (int *)(farg3);
+  result = (int)ARKodeGetStageIndex(arg1,arg2,arg3);
+  fresult = (int)(result);
+  return fresult;
+}
+
+
 SWIGEXPORT int _wrap_FARKodeGetNumExpSteps(void *farg1, long *farg2) {
   int fresult ;
   void *arg1 = (void *) 0 ;
@@ -1709,6 +1725,34 @@ SWIGEXPORT int _wrap_FARKodeGetNumLinSolvSetups(void *farg1, long *farg2) {
 }
 
 
+SWIGEXPORT int _wrap_FARKodeGetLastTime(void *farg1, double *farg2) {
+  int fresult ;
+  void *arg1 = (void *) 0 ;
+  sunrealtype *arg2 = (sunrealtype *) 0 ;
+  int result;
+  
+  arg1 = (void *)(farg1);
+  arg2 = (sunrealtype *)(farg2);
+  result = (int)ARKodeGetLastTime(arg1,arg2);
+  fresult = (int)(result);
+  return fresult;
+}
+
+
+SWIGEXPORT int _wrap_FARKodeGetLastState(void *farg1, void *farg2) {
+  int fresult ;
+  void *arg1 = (void *) 0 ;
+  N_Vector *arg2 = (N_Vector *) 0 ;
+  int result;
+  
+  arg1 = (void *)(farg1);
+  arg2 = (N_Vector *)(farg2);
+  result = (int)ARKodeGetLastState(arg1,arg2);
+  fresult = (int)(result);
+  return fresult;
+}
+
+
 SWIGEXPORT int _wrap_FARKodeGetCurrentTime(void *farg1, double *farg2) {
   int fresult ;
   void *arg1 = (void *) 0 ;
diff --git a/src/arkode/fmod_int64/farkode_mod.f90 b/src/arkode/fmod_int64/farkode_mod.f90
index 4bd678a75f..98f1541e36 100644
--- a/src/arkode/fmod_int64/farkode_mod.f90
+++ b/src/arkode/fmod_int64/farkode_mod.f90
@@ -213,6 +213,7 @@ module farkode_mod
  public :: FARKodePrintAllStats
  public :: FARKodeGetReturnFlagName
  public :: FARKodeWriteParameters
+ public :: FARKodeGetStageIndex
  public :: FARKodeGetNumExpSteps
  public :: FARKodeGetNumAccSteps
  public :: FARKodeGetNumErrTestFails
@@ -223,6 +224,8 @@ module farkode_mod
  public :: FARKodeGetStepStats
  public :: FARKodeGetAccumulatedError
  public :: FARKodeGetNumLinSolvSetups
+ public :: FARKodeGetLastTime
+ public :: FARKodeGetLastState
  public :: FARKodeGetCurrentTime
  public :: FARKodeGetCurrentState
  public :: FARKodeGetCurrentGamma
@@ -1299,6 +1302,16 @@ function swigc_FARKodeWriteParameters(farg1, farg2) &
 integer(C_INT) :: fresult
 end function
 
+function swigc_FARKodeGetStageIndex(farg1, farg2, farg3) &
+bind(C, name="_wrap_FARKodeGetStageIndex") &
+result(fresult)
+use, intrinsic :: ISO_C_BINDING
+type(C_PTR), value :: farg1
+type(C_PTR), value :: farg2
+type(C_PTR), value :: farg3
+integer(C_INT) :: fresult
+end function
+
 function swigc_FARKodeGetNumExpSteps(farg1, farg2) &
 bind(C, name="_wrap_FARKodeGetNumExpSteps") &
 result(fresult)
@@ -1393,6 +1406,24 @@ function swigc_FARKodeGetNumLinSolvSetups(farg1, farg2) &
 integer(C_INT) :: fresult
 end function
 
+function swigc_FARKodeGetLastTime(farg1, farg2) &
+bind(C, name="_wrap_FARKodeGetLastTime") &
+result(fresult)
+use, intrinsic :: ISO_C_BINDING
+type(C_PTR), value :: farg1
+type(C_PTR), value :: farg2
+integer(C_INT) :: fresult
+end function
+
+function swigc_FARKodeGetLastState(farg1, farg2) &
+bind(C, name="_wrap_FARKodeGetLastState") &
+result(fresult)
+use, intrinsic :: ISO_C_BINDING
+type(C_PTR), value :: farg1
+type(C_PTR), value :: farg2
+integer(C_INT) :: fresult
+end function
+
 function swigc_FARKodeGetCurrentTime(farg1, farg2) &
 bind(C, name="_wrap_FARKodeGetCurrentTime") &
 result(fresult)
@@ -4014,6 +4045,25 @@ function FARKodeWriteParameters(arkode_mem, fp) &
 swig_result = fresult
 end function
 
+function FARKodeGetStageIndex(arkode_mem, stage, max_stages) &
+result(swig_result)
+use, intrinsic :: ISO_C_BINDING
+integer(C_INT) :: swig_result
+type(C_PTR) :: arkode_mem
+integer(C_INT), dimension(*), target, intent(inout) :: stage
+integer(C_INT), dimension(*), target, intent(inout) :: max_stages
+integer(C_INT) :: fresult 
+type(C_PTR) :: farg1 
+type(C_PTR) :: farg2 
+type(C_PTR) :: farg3 
+
+farg1 = arkode_mem
+farg2 = c_loc(stage(1))
+farg3 = c_loc(max_stages(1))
+fresult = swigc_FARKodeGetStageIndex(farg1, farg2, farg3)
+swig_result = fresult
+end function
+
 function FARKodeGetNumExpSteps(arkode_mem, expsteps) &
 result(swig_result)
 use, intrinsic :: ISO_C_BINDING
@@ -4186,6 +4236,38 @@ function FARKodeGetNumLinSolvSetups(arkode_mem, nlinsetups) &
 swig_result = fresult
 end function
 
+function FARKodeGetLastTime(arkode_mem, tn) &
+result(swig_result)
+use, intrinsic :: ISO_C_BINDING
+integer(C_INT) :: swig_result
+type(C_PTR) :: arkode_mem
+real(C_DOUBLE), dimension(*), target, intent(inout) :: tn
+integer(C_INT) :: fresult 
+type(C_PTR) :: farg1 
+type(C_PTR) :: farg2 
+
+farg1 = arkode_mem
+farg2 = c_loc(tn(1))
+fresult = swigc_FARKodeGetLastTime(farg1, farg2)
+swig_result = fresult
+end function
+
+function FARKodeGetLastState(arkode_mem, state) &
+result(swig_result)
+use, intrinsic :: ISO_C_BINDING
+integer(C_INT) :: swig_result
+type(C_PTR) :: arkode_mem
+type(C_PTR) :: state
+integer(C_INT) :: fresult 
+type(C_PTR) :: farg1 
+type(C_PTR) :: farg2 
+
+farg1 = arkode_mem
+farg2 = state
+fresult = swigc_FARKodeGetLastState(farg1, farg2)
+swig_result = fresult
+end function
+
 function FARKodeGetCurrentTime(arkode_mem, tcur) &
 result(swig_result)
 use, intrinsic :: ISO_C_BINDING
diff --git a/test/answers b/test/answers
index 55c4feeefc..649ef300fa 160000
--- a/test/answers
+++ b/test/answers
@@ -1 +1 @@
-Subproject commit 55c4feeefc0e783e31e19b2d03fdfb85bd9f42ff
+Subproject commit 649ef300faaad58ea9981892f3525669fa7cf60a
diff --git a/test/unit_tests/arkode/CXX_serial/CMakeLists.txt b/test/unit_tests/arkode/CXX_serial/CMakeLists.txt
index 0d8484b569..121d6b5148 100644
--- a/test/unit_tests/arkode/CXX_serial/CMakeLists.txt
+++ b/test/unit_tests/arkode/CXX_serial/CMakeLists.txt
@@ -76,7 +76,27 @@ set(unit_tests
     "ark_test_prealloc_lsrkstep.cpp\;1\;"
     "ark_test_prealloc_mristep.cpp\;1\;"
     "ark_test_prealloc_splittingstep.cpp\;1\;"
-    "ark_test_prealloc_sprkstep.cpp\;1\;")
+    "ark_test_prealloc_sprkstep.cpp\;1\;"
+    "ark_test_stageinfo_arkstep.cpp\;0\;" # ERK
+    "ark_test_stageinfo_arkstep.cpp\;1\;" # DIRK
+    "ark_test_stageinfo_arkstep.cpp\;2\;" # ImEx
+    "ark_test_stageinfo_erkstep.cpp\;\;"
+    "ark_test_stageinfo_forcingstep.cpp\;\;"
+    "ark_test_stageinfo_lsrkstep.cpp\;0\;" # RKC
+    "ark_test_stageinfo_lsrkstep.cpp\;1\;" # RKL
+    "ark_test_stageinfo_lsrkstep.cpp\;2\;" # SSPs2
+    "ark_test_stageinfo_lsrkstep.cpp\;3\;" # SSPs3
+    "ark_test_stageinfo_lsrkstep.cpp\;4\;" # SSP43
+    "ark_test_stageinfo_lsrkstep.cpp\;5\;" # SSP104
+    "ark_test_stageinfo_mristep.cpp\;0\;" # MRIGARK Explicit
+    "ark_test_stageinfo_mristep.cpp\;1\;" # MRIGARK Implicit
+    "ark_test_stageinfo_mristep.cpp\;2\;" # MRIGARK ImEx
+    "ark_test_stageinfo_mristep.cpp\;3\;" # MRISR Explicit
+    "ark_test_stageinfo_mristep.cpp\;4\;" # MRISR Implicit
+    "ark_test_stageinfo_mristep.cpp\;5\;" # MRISR ImEx
+    "ark_test_stageinfo_mristep.cpp\;6\;" # MERK
+    "ark_test_stageinfo_splittingstep.cpp\;\;"
+    "ark_test_stageinfo_sprkstep.cpp\;\;")
 
 # Add the build and install targets for each test
 foreach(test_tuple ${unit_tests})
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep.cpp b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep.cpp
new file mode 100644
index 0000000000..4145c3d236
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep.cpp
@@ -0,0 +1,304 @@
+/* -----------------------------------------------------------------------------
+ * Programmer(s): Daniel R. Reynolds @ UMBC
+ * -----------------------------------------------------------------------------
+ * SUNDIALS Copyright Start
+ * Copyright (c) 2025-2026, Lawrence Livermore National Security,
+ * University of Maryland Baltimore County, and the SUNDIALS contributors.
+ * Copyright (c) 2013-2025, Lawrence Livermore National Security
+ * and Southern Methodist University.
+ * Copyright (c) 2002-2013, Lawrence Livermore National Security.
+ * All rights reserved.
+ *
+ * See the top-level LICENSE and NOTICE files for details.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ * SUNDIALS Copyright End
+ * -----------------------------------------------------------------------------
+ * Test stage information and pre/postprocessing routines in ARKStep
+ * ---------------------------------------------------------------------------*/
+
+#include <cmath>
+#include <cstdio>
+#include <iomanip>
+#include <iostream>
+#include <limits>
+
+// Include desired integrators, vectors, linear solvers, and nonlinear solvers
+#include "arkode/arkode_arkstep.h"
+#include "nvector/nvector_serial.h"
+#include "sundials/sundials_context.hpp"
+#include "sundials/sundials_matrix.h"
+#include "sunlinsol/sunlinsol_spgmr.h"
+
+#include "problems/kpr.hpp"
+#include "utilities/check_return.hpp"
+
+using namespace std;
+using namespace problems::kpr;
+
+// Store the main integrator global memory for these tests only, so that we
+// can call ARKodeGetLastTime etc in the step and stage pre/postprocessing
+// callback functions below.  This would normally be stored in user_data, but
+// here we reuse problem definitions from other tests.
+void* arkode_mem = nullptr;
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data);
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+
+int main(int argc, char* argv[])
+{
+  cout << "Start ARKStep StageInfo test" << endl;
+
+  // SUNDIALS context object for this simulation
+  sundials::Context sunctx;
+
+  // Use ERK (0) or DIRK (1) otherwise use ImEx
+  int method_type = 0;
+  if (argc > 1) { method_type = stoi(argv[1]); }
+
+  // Create initial condition
+  N_Vector y = N_VNew_Serial(2, sunctx);
+  if (check_ptr(y, "N_VNew_Serial")) { return 1; }
+
+  sunrealtype utrue, vtrue;
+  int flag = true_sol(zero, &utrue, &vtrue);
+  if (check_flag(flag, "true_sol")) { return 1; }
+
+  sunrealtype* ydata = N_VGetArrayPointer(y);
+  ydata[0]           = utrue;
+  ydata[1]           = vtrue;
+
+  // Create ARKStep memory structure
+  if (method_type == 0)
+  {
+    cout << "Using ERK method" << endl;
+    arkode_mem = ARKStepCreate(ode_rhs, nullptr, zero, y, sunctx);
+    if (check_ptr(arkode_mem, "ARKStepCreate")) { return 1; }
+  }
+  else if (method_type == 1)
+  {
+    cout << "Using DIRK method" << endl;
+    arkode_mem = ARKStepCreate(nullptr, ode_rhs, zero, y, sunctx);
+    if (check_ptr(arkode_mem, "ARKStepCreate")) { return 1; }
+  }
+  else
+  {
+    cout << "Using ImEx method" << endl;
+    arkode_mem = ARKStepCreate(ode_rhs_ex, ode_rhs_im, zero, y, sunctx);
+    if (check_ptr(arkode_mem, "ARKStepCreate")) { return 1; }
+  }
+
+  flag = ARKodeSetUserData(arkode_mem, &problem_data);
+  if (check_flag(flag, "ARKodeSetUserData")) { return 1; }
+
+  // Relative and absolute tolerances
+  const sunrealtype rtol = SUN_RCONST(1.0e-6);
+  const sunrealtype atol = SUN_RCONST(1.0e-10);
+
+  flag = ARKodeSStolerances(arkode_mem, rtol, atol);
+  if (check_flag(flag, "ARKodeSStolerances")) { return 1; }
+
+  SUNMatrix A        = nullptr;
+  SUNLinearSolver LS = nullptr;
+
+  if (method_type > 0)
+  {
+    cout << "Using Newton nonlinear solver" << endl;
+    cout << "Using GMRES iterative linear solver" << endl;
+
+    LS = SUNLinSol_SPGMR(y, SUN_PREC_NONE, 0, sunctx);
+    if (check_ptr(LS, "SUNLinSol_SPGMR")) { return 1; }
+
+    flag = ARKodeSetLinearSolver(arkode_mem, LS, A);
+    if (check_flag(flag, "ARKodeSetLinearSolver")) { return 1; }
+  }
+
+  // Set pre/post step and stage routines
+  flag = ARKodeSetPreprocessStepFn(arkode_mem, preprocess_step);
+  if (check_flag(flag, "ARKodeSetPreprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFn(arkode_mem, postprocess_step);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFailFn(arkode_mem, postprocess_step_fail);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFailFn")) { return 1; }
+  flag = ARKodeSetPreprocessRHSFn(arkode_mem, preprocess_stage);
+  if (check_flag(flag, "ARKodeSetPreprocessRHSFn")) { return 1; }
+  flag = ARKodeSetPostprocessStageFn(arkode_mem, postprocess_stage);
+  if (check_flag(flag, "ARKodeSetPostprocessStageFn")) { return 1; }
+
+  // Initial time and fist output time
+  const sunrealtype dtout = one; // output interval
+  const int nout          = 3;   // number of outputs
+  sunrealtype tret        = zero;
+  sunrealtype tout        = tret + dtout;
+
+  // Output initial contion
+  cout << scientific;
+  cout << setprecision(numeric_limits<sunrealtype>::digits10);
+  cout << "           t              ";
+  cout << "          u              ";
+  cout << "          v              ";
+  cout << "        u err            ";
+  cout << "        v err            " << endl;
+  for (int i = 0; i < 9; i++) { cout << "--------------"; }
+  cout << endl;
+
+  cout << setw(22) << tret << setw(25) << ydata[0] << setw(25) << ydata[1]
+       << setw(25) << abs(ydata[0] - utrue) << setw(25) << abs(ydata[1] - vtrue)
+       << endl;
+
+  // Advance in time
+  for (int i = 0; i < nout; i++)
+  {
+    flag = ARKodeEvolve(arkode_mem, tout, y, &tret, ARK_ONE_STEP);
+    if (check_flag(flag, "ARKode")) { return 1; }
+
+    flag = true_sol(tret, &utrue, &vtrue);
+    if (check_flag(flag, "true_sol")) { return 1; }
+
+    cout << setw(22) << tret << setw(25) << ydata[0] << setw(25) << ydata[1]
+         << setw(25) << abs(ydata[0] - utrue) << setw(25)
+         << abs(ydata[1] - vtrue) << endl;
+
+    // update output time
+    tout += dtout;
+  }
+  for (int i = 0; i < 9; i++) { cout << "--------------"; }
+  cout << endl;
+
+  // Print some final statistics
+  flag = ARKodePrintAllStats(arkode_mem, stdout, SUN_OUTPUTFORMAT_TABLE);
+  if (check_flag(flag, "ARKodePrintAllStats")) { return 1; }
+
+  // Clean up and return with successful completion
+  N_VDestroy(y);
+  SUNMatDestroy(A);
+  SUNLinSolFree(LS);
+  ARKodeFree(&arkode_mem);
+
+  cout << "End ARKStep StageInfo test" << endl;
+
+  return 0;
+}
+
+// Callback functions
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step failure processing at t = "
+            << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << ")," << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-RHS processing (stage " << stage << " of " << max_stages
+            << ") at t = " << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << "), " << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-stage processing (stage " << stage << " of "
+            << max_stages << ") at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "), "
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+/*---- end of file ----*/
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep_0.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep_0.out
new file mode 100644
index 0000000000..49bdd17c7d
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep_0.out
@@ -0,0 +1,60 @@
+Start ARKStep StageInfo test
+Using ERK method
+           t                        u                        v                      u err                    v err
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-RHS processing (stage 0 of 5) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 4.71e-08 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 2.06e-04 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Post-stage processing (stage 1 of 5) at t = 4.12e-05 (tn = 0.00e+00 , tcur = 4.12e-05), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 4.12e-05 (tn = 0.00e+00 , tcur = 4.12e-05), ||y||_2 = 2.1213203436e+00]
+    [Post-stage processing (stage 2 of 5) at t = 6.18e-05 (tn = 0.00e+00 , tcur = 6.18e-05), ||y||_2 = 2.1213200432e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 6.18e-05 (tn = 0.00e+00 , tcur = 6.18e-05), ||y||_2 = 2.1213200432e+00]
+    [Post-stage processing (stage 3 of 5) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213199340e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213199340e+00]
+    [Post-stage processing (stage 4 of 5) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Post-step processing at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04),||y||_2 = 2.1213198430e+00]
+      1.0298602561e-04         1.2247448703e+00         1.7320501952e+00         2.2204460493e-16         0.0000000000e+00
+    [Pre-step processing at t = 1.03e-04 (tn = 1.03e-04 , tcur = 1.03e-04),||y||_2 = 2.1213198430e+00]
+    [Post-stage processing (stage 1 of 5) at t = 5.97e-03 (tn = 1.03e-04 , tcur = 5.97e-03), ||y||_2 = 2.1212628048e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 5.97e-03 (tn = 1.03e-04 , tcur = 5.97e-03), ||y||_2 = 2.1212628048e+00]
+    [Post-stage processing (stage 2 of 5) at t = 8.90e-03 (tn = 1.03e-04 , tcur = 8.90e-03), ||y||_2 = 2.1151489033e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.90e-03 (tn = 1.03e-04 , tcur = 8.90e-03), ||y||_2 = 2.1151489033e+00]
+    [Post-stage processing (stage 3 of 5) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1129070894e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1129070894e+00]
+    [Post-stage processing (stage 4 of 5) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1110724436e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1110724436e+00]
+    [Post-step processing at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02),||y||_2 = 2.1110724436e+00]
+      1.4770752770e-02         1.2247225752e+00         1.7195003557e+00         2.8937936936e-08         2.5927171299e-08
+    [Pre-step processing at t = 1.48e-02 (tn = 1.48e-02 , tcur = 1.48e-02),||y||_2 = 2.1110724436e+00]
+    [Post-stage processing (stage 1 of 5) at t = 2.06e-02 (tn = 1.48e-02 , tcur = 2.06e-02), ||y||_2 = 2.1030688076e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.06e-02 (tn = 1.48e-02 , tcur = 2.06e-02), ||y||_2 = 2.1030688076e+00]
+    [Post-stage processing (stage 2 of 5) at t = 2.35e-02 (tn = 1.48e-02 , tcur = 2.35e-02), ||y||_2 = 2.0933502627e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.35e-02 (tn = 1.48e-02 , tcur = 2.35e-02), ||y||_2 = 2.0933502627e+00]
+    [Post-stage processing (stage 3 of 5) at t = 2.93e-02 (tn = 1.48e-02 , tcur = 2.93e-02), ||y||_2 = 2.0833181435e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.93e-02 (tn = 1.48e-02 , tcur = 2.93e-02), ||y||_2 = 2.0833181435e+00]
+    [Post-stage processing (stage 4 of 5) at t = 2.93e-02 (tn = 1.48e-02 , tcur = 2.93e-02), ||y||_2 = 2.0816387141e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 2.93e-02 (tn = 1.48e-02 , tcur = 2.93e-02), ||y||_2 = 2.0816387141e+00]
+    [Post-step processing at t = 2.93e-02 (tn = 1.48e-02 , tcur = 2.93e-02),||y||_2 = 2.0816387141e+00]
+      2.9275139161e-02         1.2246573481e+00         1.6832807581e+00         5.5763322404e-08         6.7822652161e-08
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.0292751391609328
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 3
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.000102986025609508
+Last step size                = 0.0145043863910885
+Current step size             = 0.0149829090634053
+Explicit RHS fn evals         = 15
+Implicit RHS fn evals         = 0
+NLS iters                     = 0
+NLS fails                     = 0
+NLS iters per step            = 0
+LS setups                     = 0
+End ARKStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep_1.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep_1.out
new file mode 100644
index 0000000000..86966c499a
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep_1.out
@@ -0,0 +1,144 @@
+Start ARKStep StageInfo test
+Using DIRK method
+Using Newton nonlinear solver
+Using GMRES iterative linear solver
+           t                        u                        v                      u err                    v err            
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-RHS processing (stage 0 of 6) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 6) at t = 4.71e-08 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 6) at t = 2.06e-04 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 5.15e-05 (tn = 0.00e+00 , tcur = 5.15e-05), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 5.15e-05 (tn = 0.00e+00 , tcur = 5.15e-05), ||y||_2 = 2.1213183410e+00]
+    [Post-stage processing (stage 1 of 6) at t = 5.15e-05 (tn = 0.00e+00 , tcur = 5.15e-05), ||y||_2 = 2.1213202184e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 5.15e-05 (tn = 0.00e+00 , tcur = 5.15e-05), ||y||_2 = 2.1213202184e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 1.51e-05 (tn = 0.00e+00 , tcur = 1.51e-05), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 1.51e-05 (tn = 0.00e+00 , tcur = 1.51e-05), ||y||_2 = 2.1213183410e+00]
+    [Post-stage processing (stage 2 of 6) at t = 1.51e-05 (tn = 0.00e+00 , tcur = 1.51e-05), ||y||_2 = 2.1213203328e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 1.51e-05 (tn = 0.00e+00 , tcur = 1.51e-05), ||y||_2 = 2.1213203328e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 6.44e-05 (tn = 0.00e+00 , tcur = 6.44e-05), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 6.44e-05 (tn = 0.00e+00 , tcur = 6.44e-05), ||y||_2 = 2.1213183410e+00]
+    [Post-stage processing (stage 3 of 6) at t = 6.44e-05 (tn = 0.00e+00 , tcur = 6.44e-05), ||y||_2 = 2.1213201480e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 6.44e-05 (tn = 0.00e+00 , tcur = 6.44e-05), ||y||_2 = 2.1213201480e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 1.07e-04 (tn = 0.00e+00 , tcur = 1.07e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 1.07e-04 (tn = 0.00e+00 , tcur = 1.07e-04), ||y||_2 = 2.1213183410e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 1.07e-04 (tn = 0.00e+00 , tcur = 1.07e-04), ||y||_2 = 2.1213198021e+00]
+    [Post-stage processing (stage 4 of 6) at t = 1.07e-04 (tn = 0.00e+00 , tcur = 1.07e-04), ||y||_2 = 2.1213198021e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 1.07e-04 (tn = 0.00e+00 , tcur = 1.07e-04), ||y||_2 = 2.1213198021e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213183410e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Post-stage processing (stage 5 of 6) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Post-step processing at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04),||y||_2 = 2.1213198430e+00]
+      1.0298602561e-04         1.2247448703e+00         1.7320501952e+00         7.8541617654e-12         2.7311486406e-14
+    [Pre-step processing at t = 1.03e-04 (tn = 1.03e-04 , tcur = 1.03e-04),||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 8.22e-03 (tn = 1.03e-04 , tcur = 8.22e-03), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 8.22e-03 (tn = 1.03e-04 , tcur = 8.22e-03), ||y||_2 = 2.1213178432e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 8.22e-03 (tn = 1.03e-04 , tcur = 8.22e-03), ||y||_2 = 2.1213208437e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 8.22e-03 (tn = 1.03e-04 , tcur = 8.22e-03), ||y||_2 = 2.1181363161e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 8.22e-03 (tn = 1.03e-04 , tcur = 8.22e-03), ||y||_2 = 2.1181350533e+00]
+    [Post-stage processing (stage 1 of 6) at t = 8.22e-03 (tn = 1.03e-04 , tcur = 8.22e-03), ||y||_2 = 2.1181363096e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 8.22e-03 (tn = 1.03e-04 , tcur = 8.22e-03), ||y||_2 = 2.1181363096e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 2.48e-03 (tn = 1.03e-04 , tcur = 2.48e-03), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 2.48e-03 (tn = 1.03e-04 , tcur = 2.48e-03), ||y||_2 = 2.1213178432e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 2.48e-03 (tn = 1.03e-04 , tcur = 2.48e-03), ||y||_2 = 2.1213208437e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 2.48e-03 (tn = 1.03e-04 , tcur = 2.48e-03), ||y||_2 = 2.1210284133e+00]
+    [Post-stage processing (stage 2 of 6) at t = 2.48e-03 (tn = 1.03e-04 , tcur = 2.48e-03), ||y||_2 = 2.1210284133e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 2.48e-03 (tn = 1.03e-04 , tcur = 2.48e-03), ||y||_2 = 2.1210284133e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 1.03e-02 (tn = 1.03e-04 , tcur = 1.03e-02), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 1.03e-02 (tn = 1.03e-04 , tcur = 1.03e-02), ||y||_2 = 2.1213178432e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 1.03e-02 (tn = 1.03e-04 , tcur = 1.03e-02), ||y||_2 = 2.1213208437e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 1.03e-02 (tn = 1.03e-04 , tcur = 1.03e-02), ||y||_2 = 2.1163722075e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 1.03e-02 (tn = 1.03e-04 , tcur = 1.03e-02), ||y||_2 = 2.1163703971e+00]
+    [Post-stage processing (stage 3 of 6) at t = 1.03e-02 (tn = 1.03e-04 , tcur = 1.03e-02), ||y||_2 = 2.1163721824e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 1.03e-02 (tn = 1.03e-04 , tcur = 1.03e-02), ||y||_2 = 2.1163721824e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 1.70e-02 (tn = 1.03e-04 , tcur = 1.70e-02), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 1.70e-02 (tn = 1.03e-04 , tcur = 1.70e-02), ||y||_2 = 2.1213178432e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 1.70e-02 (tn = 1.03e-04 , tcur = 1.70e-02), ||y||_2 = 2.1213208437e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 1.70e-02 (tn = 1.03e-04 , tcur = 1.70e-02), ||y||_2 = 2.1077899282e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 1.70e-02 (tn = 1.03e-04 , tcur = 1.70e-02), ||y||_2 = 2.1077876968e+00]
+    [Post-stage processing (stage 4 of 6) at t = 1.70e-02 (tn = 1.03e-04 , tcur = 1.70e-02), ||y||_2 = 2.1077895068e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 1.70e-02 (tn = 1.03e-04 , tcur = 1.70e-02), ||y||_2 = 2.1077895068e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 1.63e-02 (tn = 1.03e-04 , tcur = 1.63e-02), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 1.63e-02 (tn = 1.03e-04 , tcur = 1.63e-02), ||y||_2 = 2.1213178432e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 1.63e-02 (tn = 1.03e-04 , tcur = 1.63e-02), ||y||_2 = 2.1213208437e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 1.63e-02 (tn = 1.03e-04 , tcur = 1.63e-02), ||y||_2 = 2.1087855077e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 1.63e-02 (tn = 1.03e-04 , tcur = 1.63e-02), ||y||_2 = 2.1087832801e+00]
+    [Post-stage processing (stage 5 of 6) at t = 1.63e-02 (tn = 1.03e-04 , tcur = 1.63e-02), ||y||_2 = 2.1087851653e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 1.63e-02 (tn = 1.03e-04 , tcur = 1.63e-02), ||y||_2 = 2.1087851653e+00]
+    [Post-step processing at t = 1.63e-02 (tn = 1.03e-04 , tcur = 1.63e-02),||y||_2 = 2.1087851653e+00]
+      1.6345098954e-02         1.2247176001e+00         1.7166949855e+00         4.4663852616e-09         6.0447387096e-09
+    [Pre-step processing at t = 1.63e-02 (tn = 1.63e-02 , tcur = 1.63e-02),||y||_2 = 2.1087851653e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 2.44e-02 (tn = 1.63e-02 , tcur = 2.44e-02), ||y||_2 = 2.1087851653e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 2.44e-02 (tn = 1.63e-02 , tcur = 2.44e-02), ||y||_2 = 2.1087831891e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 2.44e-02 (tn = 1.63e-02 , tcur = 2.44e-02), ||y||_2 = 2.1087861718e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 2.44e-02 (tn = 1.63e-02 , tcur = 2.44e-02), ||y||_2 = 2.0935038900e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 2.44e-02 (tn = 1.63e-02 , tcur = 2.44e-02), ||y||_2 = 2.0935017090e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 2.44e-02 (tn = 1.63e-02 , tcur = 2.44e-02), ||y||_2 = 2.0935030131e+00]
+    [Post-stage processing (stage 1 of 6) at t = 2.44e-02 (tn = 1.63e-02 , tcur = 2.44e-02), ||y||_2 = 2.0935030131e+00]
+    [Pre-RHS processing (stage 1 of 6) at t = 2.44e-02 (tn = 1.63e-02 , tcur = 2.44e-02), ||y||_2 = 2.0935030131e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 1.87e-02 (tn = 1.63e-02 , tcur = 1.87e-02), ||y||_2 = 2.1087851653e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 1.87e-02 (tn = 1.63e-02 , tcur = 1.87e-02), ||y||_2 = 2.1087831891e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 1.87e-02 (tn = 1.63e-02 , tcur = 1.87e-02), ||y||_2 = 2.1087861719e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 1.87e-02 (tn = 1.63e-02 , tcur = 1.87e-02), ||y||_2 = 2.1049048432e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 1.87e-02 (tn = 1.63e-02 , tcur = 1.87e-02), ||y||_2 = 2.1049026275e+00]
+    [Post-stage processing (stage 2 of 6) at t = 1.87e-02 (tn = 1.63e-02 , tcur = 1.87e-02), ||y||_2 = 2.1049048030e+00]
+    [Pre-RHS processing (stage 2 of 6) at t = 1.87e-02 (tn = 1.63e-02 , tcur = 1.87e-02), ||y||_2 = 2.1049048030e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 2.65e-02 (tn = 1.63e-02 , tcur = 2.65e-02), ||y||_2 = 2.1087851653e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 2.65e-02 (tn = 1.63e-02 , tcur = 2.65e-02), ||y||_2 = 2.1087831891e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 2.65e-02 (tn = 1.63e-02 , tcur = 2.65e-02), ||y||_2 = 2.1087861718e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 2.65e-02 (tn = 1.63e-02 , tcur = 2.65e-02), ||y||_2 = 2.0887688409e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 2.65e-02 (tn = 1.63e-02 , tcur = 2.65e-02), ||y||_2 = 2.0887666742e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 2.65e-02 (tn = 1.63e-02 , tcur = 2.65e-02), ||y||_2 = 2.0887671857e+00]
+    [Post-stage processing (stage 3 of 6) at t = 2.65e-02 (tn = 1.63e-02 , tcur = 2.65e-02), ||y||_2 = 2.0887671857e+00]
+    [Pre-RHS processing (stage 3 of 6) at t = 2.65e-02 (tn = 1.63e-02 , tcur = 2.65e-02), ||y||_2 = 2.0887671857e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 3.32e-02 (tn = 1.63e-02 , tcur = 3.32e-02), ||y||_2 = 2.1087851653e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 3.32e-02 (tn = 1.63e-02 , tcur = 3.32e-02), ||y||_2 = 2.1087831890e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 3.32e-02 (tn = 1.63e-02 , tcur = 3.32e-02), ||y||_2 = 2.1087861717e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 3.32e-02 (tn = 1.63e-02 , tcur = 3.32e-02), ||y||_2 = 2.0706044622e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 3.32e-02 (tn = 1.63e-02 , tcur = 3.32e-02), ||y||_2 = 2.0706023387e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 3.32e-02 (tn = 1.63e-02 , tcur = 3.32e-02), ||y||_2 = 2.0705966594e+00]
+    [Post-stage processing (stage 4 of 6) at t = 3.32e-02 (tn = 1.63e-02 , tcur = 3.32e-02), ||y||_2 = 2.0705966594e+00]
+    [Pre-RHS processing (stage 4 of 6) at t = 3.32e-02 (tn = 1.63e-02 , tcur = 3.32e-02), ||y||_2 = 2.0705966594e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 3.25e-02 (tn = 1.63e-02 , tcur = 3.25e-02), ||y||_2 = 2.1087851653e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 3.25e-02 (tn = 1.63e-02 , tcur = 3.25e-02), ||y||_2 = 2.1087831890e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 3.25e-02 (tn = 1.63e-02 , tcur = 3.25e-02), ||y||_2 = 2.1087861718e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 3.25e-02 (tn = 1.63e-02 , tcur = 3.25e-02), ||y||_2 = 2.0725003000e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 3.25e-02 (tn = 1.63e-02 , tcur = 3.25e-02), ||y||_2 = 2.0724981727e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 3.25e-02 (tn = 1.63e-02 , tcur = 3.25e-02), ||y||_2 = 2.0724934048e+00]
+    [Post-stage processing (stage 5 of 6) at t = 3.25e-02 (tn = 1.63e-02 , tcur = 3.25e-02), ||y||_2 = 2.0724934048e+00]
+    [Pre-RHS processing (stage 5 of 6) at t = 3.25e-02 (tn = 1.63e-02 , tcur = 3.25e-02), ||y||_2 = 2.0724934048e+00]
+    [Post-step processing at t = 3.25e-02 (tn = 1.63e-02 , tcur = 3.25e-02),||y||_2 = 2.0724934048e+00]
+      3.2548715292e-02         1.2246367417e+00         1.6719730154e+00         8.0260507129e-09         5.9880216341e-09
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.0325487152923576
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 3
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.000102986025609508
+Last step size                = 0.0162036163379197
+Current step size             = 0.0160003634180696
+Explicit RHS fn evals         = 0
+Implicit RHS fn evals         = 49
+NLS iters                     = 31
+NLS fails                     = 0
+NLS iters per step            = 10.3333333333333
+LS setups                     = 0
+Jac fn evals                  = 0
+LS RHS fn evals               = 34
+Prec setup evals              = 0
+Prec solves                   = 0
+LS iters                      = 34
+LS fails                      = 0
+Jac-times setups              = 0
+Jac-times evals               = 34
+LS iters per NLS iter         = 1.09677419354839
+Jac evals per NLS iter        = 0
+Prec evals per NLS iter       = 0
+End ARKStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep_2.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep_2.out
new file mode 100644
index 0000000000..0c42465ad2
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_arkstep_2.out
@@ -0,0 +1,172 @@
+Start ARKStep StageInfo test
+Using ImEx method
+Using Newton nonlinear solver
+Using GMRES iterative linear solver
+           t                        u                        v                      u err                    v err            
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-RHS processing (stage 0 of 7) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 7) at t = 4.71e-08 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 7) at t = 2.06e-04 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 2.54e-05 (tn = 0.00e+00 , tcur = 2.54e-05), ||y||_2 = 2.1213203436e+00]
+    [Post-stage processing (stage 1 of 7) at t = 2.54e-05 (tn = 0.00e+00 , tcur = 2.54e-05), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 2.54e-05 (tn = 0.00e+00 , tcur = 2.54e-05), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.34e-05 (tn = 0.00e+00 , tcur = 4.34e-05), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.34e-05 (tn = 0.00e+00 , tcur = 4.34e-05), ||y||_2 = 2.1213183410e+00]
+    [Post-stage processing (stage 2 of 7) at t = 4.34e-05 (tn = 0.00e+00 , tcur = 4.34e-05), ||y||_2 = 2.1213202546e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.34e-05 (tn = 0.00e+00 , tcur = 4.34e-05), ||y||_2 = 2.1213202546e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 3.45e-05 (tn = 0.00e+00 , tcur = 3.45e-05), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 3.45e-05 (tn = 0.00e+00 , tcur = 3.45e-05), ||y||_2 = 2.1213183410e+00]
+    [Post-stage processing (stage 3 of 7) at t = 3.45e-05 (tn = 0.00e+00 , tcur = 3.45e-05), ||y||_2 = 2.1213202874e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 3.45e-05 (tn = 0.00e+00 , tcur = 3.45e-05), ||y||_2 = 2.1213202874e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 7.72e-06 (tn = 0.00e+00 , tcur = 7.72e-06), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 7.72e-06 (tn = 0.00e+00 , tcur = 7.72e-06), ||y||_2 = 2.1213183409e+00]
+    [Post-stage processing (stage 4 of 7) at t = 7.72e-06 (tn = 0.00e+00 , tcur = 7.72e-06), ||y||_2 = 2.1213203407e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 7.72e-06 (tn = 0.00e+00 , tcur = 7.72e-06), ||y||_2 = 2.1213203407e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 7.21e-05 (tn = 0.00e+00 , tcur = 7.21e-05), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 7.21e-05 (tn = 0.00e+00 , tcur = 7.21e-05), ||y||_2 = 2.1213183410e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 7.21e-05 (tn = 0.00e+00 , tcur = 7.21e-05), ||y||_2 = 2.1213200983e+00]
+    [Post-stage processing (stage 5 of 7) at t = 7.21e-05 (tn = 0.00e+00 , tcur = 7.21e-05), ||y||_2 = 2.1213200983e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 7.21e-05 (tn = 0.00e+00 , tcur = 7.21e-05), ||y||_2 = 2.1213200983e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213183410e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Post-stage processing (stage 6 of 7) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Post-step processing at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04),||y||_2 = 2.1213198430e+00]
+      1.0298602561e-04         1.2247448703e+00         1.7320501952e+00         2.2204460493e-16         0.0000000000e+00
+    [Pre-step processing at t = 1.03e-04 (tn = 1.03e-04 , tcur = 1.03e-04),||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 0 of 7) at t = 1.03e-04 (tn = 1.03e-04 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 8.73e-03 (tn = 1.03e-04 , tcur = 8.73e-03), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 8.73e-03 (tn = 1.03e-04 , tcur = 8.73e-03), ||y||_2 = 2.1213179609e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 8.73e-03 (tn = 1.03e-04 , tcur = 8.73e-03), ||y||_2 = 2.1213210506e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 8.73e-03 (tn = 1.03e-04 , tcur = 8.73e-03), ||y||_2 = 2.1212262228e+00]
+    [Post-stage processing (stage 1 of 7) at t = 8.73e-03 (tn = 1.03e-04 , tcur = 8.73e-03), ||y||_2 = 2.1212262228e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 8.73e-03 (tn = 1.03e-04 , tcur = 8.73e-03), ||y||_2 = 2.1212262228e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1213178446e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1213208465e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1109952863e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1109963352e+00]
+    [Post-stage processing (stage 2 of 7) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1109953892e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 1.48e-02 (tn = 1.03e-04 , tcur = 1.48e-02), ||y||_2 = 2.1109953892e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 1.18e-02 (tn = 1.03e-04 , tcur = 1.18e-02), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 1.18e-02 (tn = 1.03e-04 , tcur = 1.18e-02), ||y||_2 = 2.1213178450e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 1.18e-02 (tn = 1.03e-04 , tcur = 1.18e-02), ||y||_2 = 2.1213208473e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 1.18e-02 (tn = 1.03e-04 , tcur = 1.18e-02), ||y||_2 = 2.1147654560e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 1.18e-02 (tn = 1.03e-04 , tcur = 1.18e-02), ||y||_2 = 2.1147665074e+00]
+    [Post-stage processing (stage 3 of 7) at t = 1.18e-02 (tn = 1.03e-04 , tcur = 1.18e-02), ||y||_2 = 2.1147654976e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 1.18e-02 (tn = 1.03e-04 , tcur = 1.18e-02), ||y||_2 = 2.1147654976e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 2.72e-03 (tn = 1.03e-04 , tcur = 2.72e-03), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 2.72e-03 (tn = 1.03e-04 , tcur = 2.72e-03), ||y||_2 = 2.1213178266e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 2.72e-03 (tn = 1.03e-04 , tcur = 2.72e-03), ||y||_2 = 2.1213208099e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 2.72e-03 (tn = 1.03e-04 , tcur = 2.72e-03), ||y||_2 = 2.1209503426e+00]
+    [Post-stage processing (stage 4 of 7) at t = 2.72e-03 (tn = 1.03e-04 , tcur = 2.72e-03), ||y||_2 = 2.1209503426e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 2.72e-03 (tn = 1.03e-04 , tcur = 2.72e-03), ||y||_2 = 2.1209503426e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 2.45e-02 (tn = 1.03e-04 , tcur = 2.45e-02), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 2.45e-02 (tn = 1.03e-04 , tcur = 2.45e-02), ||y||_2 = 2.1213178428e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 2.45e-02 (tn = 1.03e-04 , tcur = 2.45e-02), ||y||_2 = 2.1213208430e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 2.45e-02 (tn = 1.03e-04 , tcur = 2.45e-02), ||y||_2 = 2.0932810331e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 2.45e-02 (tn = 1.03e-04 , tcur = 2.45e-02), ||y||_2 = 2.0932820701e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 2.45e-02 (tn = 1.03e-04 , tcur = 2.45e-02), ||y||_2 = 2.0932790587e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 2.45e-02 (tn = 1.03e-04 , tcur = 2.45e-02), ||y||_2 = 2.0932817810e+00]
+    [Post-stage processing (stage 5 of 7) at t = 2.45e-02 (tn = 1.03e-04 , tcur = 2.45e-02), ||y||_2 = 2.0932817810e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 2.45e-02 (tn = 1.03e-04 , tcur = 2.45e-02), ||y||_2 = 2.0932817810e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 3.50e-02 (tn = 1.03e-04 , tcur = 3.50e-02), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 3.50e-02 (tn = 1.03e-04 , tcur = 3.50e-02), ||y||_2 = 2.1213178433e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 3.50e-02 (tn = 1.03e-04 , tcur = 3.50e-02), ||y||_2 = 2.1213208439e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 3.50e-02 (tn = 1.03e-04 , tcur = 3.50e-02), ||y||_2 = 2.0649440080e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 3.50e-02 (tn = 1.03e-04 , tcur = 3.50e-02), ||y||_2 = 2.0649450254e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 3.50e-02 (tn = 1.03e-04 , tcur = 3.50e-02), ||y||_2 = 2.0649420305e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 3.50e-02 (tn = 1.03e-04 , tcur = 3.50e-02), ||y||_2 = 2.0649469358e+00]
+    [Post-stage processing (stage 6 of 7) at t = 3.50e-02 (tn = 1.03e-04 , tcur = 3.50e-02), ||y||_2 = 2.0649469358e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 3.50e-02 (tn = 1.03e-04 , tcur = 3.50e-02), ||y||_2 = 2.0649469358e+00]
+    [Post-step processing at t = 3.50e-02 (tn = 1.03e-04 , tcur = 3.50e-02),||y||_2 = 2.0649991558e+00]
+      3.5024521932e-02         1.2246196097e+00         1.6626870797e+00         6.6819398681e-08         6.5525542281e-07
+    [Pre-step processing at t = 3.50e-02 (tn = 3.50e-02 , tcur = 3.50e-02),||y||_2 = 2.0649991558e+00]
+    [Pre-RHS processing (stage 0 of 7) at t = 3.50e-02 (tn = 3.50e-02 , tcur = 3.50e-02), ||y||_2 = 2.0649991558e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 4.36e-02 (tn = 3.50e-02 , tcur = 4.36e-02), ||y||_2 = 2.0649991558e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 4.36e-02 (tn = 3.50e-02 , tcur = 4.36e-02), ||y||_2 = 2.0649972631e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 4.36e-02 (tn = 3.50e-02 , tcur = 4.36e-02), ||y||_2 = 2.0650001842e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 4.36e-02 (tn = 3.50e-02 , tcur = 4.36e-02), ||y||_2 = 2.0383154536e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 4.36e-02 (tn = 3.50e-02 , tcur = 4.36e-02), ||y||_2 = 2.0383164246e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 4.36e-02 (tn = 3.50e-02 , tcur = 4.36e-02), ||y||_2 = 2.0383135369e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 4.36e-02 (tn = 3.50e-02 , tcur = 4.36e-02), ||y||_2 = 2.0383161449e+00]
+    [Post-stage processing (stage 1 of 7) at t = 4.36e-02 (tn = 3.50e-02 , tcur = 4.36e-02), ||y||_2 = 2.0383161449e+00]
+    [Pre-RHS processing (stage 1 of 7) at t = 4.36e-02 (tn = 3.50e-02 , tcur = 4.36e-02), ||y||_2 = 2.0383161449e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.96e-02 (tn = 3.50e-02 , tcur = 4.96e-02), ||y||_2 = 2.0649991558e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.96e-02 (tn = 3.50e-02 , tcur = 4.96e-02), ||y||_2 = 2.0649972629e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.96e-02 (tn = 3.50e-02 , tcur = 4.96e-02), ||y||_2 = 2.0650001838e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.96e-02 (tn = 3.50e-02 , tcur = 4.96e-02), ||y||_2 = 2.0114167342e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.96e-02 (tn = 3.50e-02 , tcur = 4.96e-02), ||y||_2 = 2.0114176855e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.96e-02 (tn = 3.50e-02 , tcur = 4.96e-02), ||y||_2 = 2.0114148140e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.96e-02 (tn = 3.50e-02 , tcur = 4.96e-02), ||y||_2 = 2.0114194404e+00]
+    [Post-stage processing (stage 2 of 7) at t = 4.96e-02 (tn = 3.50e-02 , tcur = 4.96e-02), ||y||_2 = 2.0114194404e+00]
+    [Pre-RHS processing (stage 2 of 7) at t = 4.96e-02 (tn = 3.50e-02 , tcur = 4.96e-02), ||y||_2 = 2.0114194404e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 4.66e-02 (tn = 3.50e-02 , tcur = 4.66e-02), ||y||_2 = 2.0649991558e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 4.66e-02 (tn = 3.50e-02 , tcur = 4.66e-02), ||y||_2 = 2.0649972629e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 4.66e-02 (tn = 3.50e-02 , tcur = 4.66e-02), ||y||_2 = 2.0650001839e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 4.66e-02 (tn = 3.50e-02 , tcur = 4.66e-02), ||y||_2 = 2.0236350168e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 4.66e-02 (tn = 3.50e-02 , tcur = 4.66e-02), ||y||_2 = 2.0236359771e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 4.66e-02 (tn = 3.50e-02 , tcur = 4.66e-02), ||y||_2 = 2.0236330982e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 4.66e-02 (tn = 3.50e-02 , tcur = 4.66e-02), ||y||_2 = 2.0236366549e+00]
+    [Post-stage processing (stage 3 of 7) at t = 4.66e-02 (tn = 3.50e-02 , tcur = 4.66e-02), ||y||_2 = 2.0236366549e+00]
+    [Pre-RHS processing (stage 3 of 7) at t = 4.66e-02 (tn = 3.50e-02 , tcur = 4.66e-02), ||y||_2 = 2.0236366549e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 3.76e-02 (tn = 3.50e-02 , tcur = 3.76e-02), ||y||_2 = 2.0649991558e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 3.76e-02 (tn = 3.50e-02 , tcur = 3.76e-02), ||y||_2 = 2.0649972622e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 3.76e-02 (tn = 3.50e-02 , tcur = 3.76e-02), ||y||_2 = 2.0650001825e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 3.76e-02 (tn = 3.50e-02 , tcur = 3.76e-02), ||y||_2 = 2.0565069828e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 3.76e-02 (tn = 3.50e-02 , tcur = 3.76e-02), ||y||_2 = 2.0565079665e+00]
+    [Post-stage processing (stage 4 of 7) at t = 3.76e-02 (tn = 3.50e-02 , tcur = 3.76e-02), ||y||_2 = 2.0565070541e+00]
+    [Pre-RHS processing (stage 4 of 7) at t = 3.76e-02 (tn = 3.50e-02 , tcur = 3.76e-02), ||y||_2 = 2.0565070541e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 5.93e-02 (tn = 3.50e-02 , tcur = 5.93e-02), ||y||_2 = 2.0649991558e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 5.93e-02 (tn = 3.50e-02 , tcur = 5.93e-02), ||y||_2 = 2.0649972625e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 5.93e-02 (tn = 3.50e-02 , tcur = 5.93e-02), ||y||_2 = 2.0650001830e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 5.93e-02 (tn = 3.50e-02 , tcur = 5.93e-02), ||y||_2 = 1.9686832168e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 5.93e-02 (tn = 3.50e-02 , tcur = 5.93e-02), ||y||_2 = 1.9686841353e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 5.93e-02 (tn = 3.50e-02 , tcur = 5.93e-02), ||y||_2 = 1.9686812913e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 5.93e-02 (tn = 3.50e-02 , tcur = 5.93e-02), ||y||_2 = 1.9686914710e+00]
+    [Post-stage processing (stage 5 of 7) at t = 5.93e-02 (tn = 3.50e-02 , tcur = 5.93e-02), ||y||_2 = 1.9686914710e+00]
+    [Pre-RHS processing (stage 5 of 7) at t = 5.93e-02 (tn = 3.50e-02 , tcur = 5.93e-02), ||y||_2 = 1.9686914710e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 6.97e-02 (tn = 3.50e-02 , tcur = 6.97e-02), ||y||_2 = 2.0649991558e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 6.97e-02 (tn = 3.50e-02 , tcur = 6.97e-02), ||y||_2 = 2.0649972625e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 6.97e-02 (tn = 3.50e-02 , tcur = 6.97e-02), ||y||_2 = 2.0650001830e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 6.97e-02 (tn = 3.50e-02 , tcur = 6.97e-02), ||y||_2 = 1.9163575635e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 6.97e-02 (tn = 3.50e-02 , tcur = 6.97e-02), ||y||_2 = 1.9163584389e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 6.97e-02 (tn = 3.50e-02 , tcur = 6.97e-02), ||y||_2 = 1.9163556320e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 6.97e-02 (tn = 3.50e-02 , tcur = 6.97e-02), ||y||_2 = 1.9163758117e+00]
+    [Post-stage processing (stage 6 of 7) at t = 6.97e-02 (tn = 3.50e-02 , tcur = 6.97e-02), ||y||_2 = 1.9163758117e+00]
+    [Pre-RHS processing (stage 6 of 7) at t = 6.97e-02 (tn = 3.50e-02 , tcur = 6.97e-02), ||y||_2 = 1.9163758117e+00]
+    [Post-step processing at t = 6.97e-02 (tn = 3.50e-02 , tcur = 6.97e-02),||y||_2 = 1.9169542285e+00]
+      6.9697813939e-02         1.2242491983e+00         1.4751025098e+00         2.2221884333e-08         2.5857302401e-06
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.0696978139393375
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 3
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.000102986025609508
+Last step size                = 0.0346732920075373
+Current step size             = 0.0331306528243113
+Explicit RHS fn evals         = 23
+Implicit RHS fn evals         = 62
+NLS iters                     = 39
+NLS fails                     = 0
+NLS iters per step            = 13
+LS setups                     = 0
+Jac fn evals                  = 0
+LS RHS fn evals               = 46
+Prec setup evals              = 0
+Prec solves                   = 0
+LS iters                      = 46
+LS fails                      = 0
+Jac-times setups              = 0
+Jac-times evals               = 46
+LS iters per NLS iter         = 1.17948717948718
+Jac evals per NLS iter        = 0
+Prec evals per NLS iter       = 0
+End ARKStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_erkstep.cpp b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_erkstep.cpp
new file mode 100644
index 0000000000..375bee9e5c
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_erkstep.cpp
@@ -0,0 +1,265 @@
+/* -----------------------------------------------------------------------------
+ * Programmer(s): Daniel R. Reynolds @ UMBC
+ * -----------------------------------------------------------------------------
+ * SUNDIALS Copyright Start
+ * Copyright (c) 2025-2026, Lawrence Livermore National Security,
+ * University of Maryland Baltimore County, and the SUNDIALS contributors.
+ * Copyright (c) 2013-2025, Lawrence Livermore National Security
+ * and Southern Methodist University.
+ * Copyright (c) 2002-2013, Lawrence Livermore National Security.
+ * All rights reserved.
+ *
+ * See the top-level LICENSE and NOTICE files for details.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ * SUNDIALS Copyright End
+ * -----------------------------------------------------------------------------
+ * Test stage information and pre/postprocessing routines in ERKStep
+ * ---------------------------------------------------------------------------*/
+
+#include <cmath>
+#include <cstdio>
+#include <iomanip>
+#include <iostream>
+#include <limits>
+
+// Include desired integrators, vectors, linear solvers, and nonlinear solvers
+#include "arkode/arkode_erkstep.h"
+#include "nvector/nvector_serial.h"
+#include "sundials/sundials_context.hpp"
+
+#include "problems/kpr.hpp"
+#include "utilities/check_return.hpp"
+
+using namespace std;
+using namespace problems::kpr;
+
+// Store the main integrator global memory for these tests only, so that we
+// can call ARKodeGetLastTime etc in the step and stage pre/postprocessing
+// callback functions below.  This would normally be stored in user_data, but
+// here we reuse problem definitions from other tests.
+void* arkode_mem = nullptr;
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data);
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+
+int main(int argc, char* argv[])
+{
+  cout << "Start ERKStep StageInfo test" << endl;
+
+  // SUNDIALS context object for this simulation
+  sundials::Context sunctx;
+
+  // Create initial condition
+  N_Vector y = N_VNew_Serial(2, sunctx);
+  if (check_ptr(y, "N_VNew_Serial")) { return 1; }
+
+  sunrealtype utrue, vtrue;
+  int flag = true_sol(zero, &utrue, &vtrue);
+  if (check_flag(flag, "true_sol")) { return 1; }
+
+  sunrealtype* ydata = N_VGetArrayPointer(y);
+  ydata[0]           = utrue;
+  ydata[1]           = vtrue;
+
+  // Create ERKStep memory structure
+  arkode_mem = ERKStepCreate(ode_rhs, zero, y, sunctx);
+  if (check_ptr(arkode_mem, "ERKStepCreate")) { return 1; }
+
+  flag = ARKodeSetUserData(arkode_mem, &problem_data);
+  if (check_flag(flag, "ARKodeSetUserData")) { return 1; }
+
+  // Relative and absolute tolerances
+  const sunrealtype rtol = SUN_RCONST(1.0e-6);
+  const sunrealtype atol = SUN_RCONST(1.0e-10);
+
+  flag = ARKodeSStolerances(arkode_mem, rtol, atol);
+  if (check_flag(flag, "ARKodeSStolerances")) { return 1; }
+
+  // Set pre/post step and stage routines
+  flag = ARKodeSetPreprocessStepFn(arkode_mem, preprocess_step);
+  if (check_flag(flag, "ARKodeSetPreprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFn(arkode_mem, postprocess_step);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFailFn(arkode_mem, postprocess_step_fail);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFailFn")) { return 1; }
+  flag = ARKodeSetPreprocessRHSFn(arkode_mem, preprocess_stage);
+  if (check_flag(flag, "ARKodeSetPreprocessRHSFn")) { return 1; }
+  flag = ARKodeSetPostprocessStageFn(arkode_mem, postprocess_stage);
+  if (check_flag(flag, "ARKodeSetPostprocessStageFn")) { return 1; }
+
+  // Initial time and fist output time
+  const sunrealtype dtout = one; // output interval
+  const int nout          = 3;   // number of outputs
+  sunrealtype tret        = zero;
+  sunrealtype tout        = tret + dtout;
+
+  // Output initial contion
+  cout << scientific;
+  cout << setprecision(numeric_limits<sunrealtype>::digits10);
+  cout << "           t              ";
+  cout << "          u              ";
+  cout << "          v              ";
+  cout << "        u err            ";
+  cout << "        v err            " << endl;
+  for (int i = 0; i < 9; i++) { cout << "--------------"; }
+  cout << endl;
+
+  cout << setw(22) << tret << setw(25) << ydata[0] << setw(25) << ydata[1]
+       << setw(25) << abs(ydata[0] - utrue) << setw(25) << abs(ydata[1] - vtrue)
+       << endl;
+
+  // Advance in time
+  for (int i = 0; i < nout; i++)
+  {
+    flag = ARKodeEvolve(arkode_mem, tout, y, &tret, ARK_ONE_STEP);
+    if (check_flag(flag, "ARKodeEvolve")) { return 1; }
+
+    flag = true_sol(tret, &utrue, &vtrue);
+    if (check_flag(flag, "true_sol")) { return 1; }
+
+    cout << setw(22) << tret << setw(25) << ydata[0] << setw(25) << ydata[1]
+         << setw(25) << abs(ydata[0] - utrue) << setw(25)
+         << abs(ydata[1] - vtrue) << endl;
+
+    // update output time
+    tout += dtout;
+  }
+  for (int i = 0; i < 9; i++) { cout << "--------------"; }
+  cout << endl;
+
+  // Print some final statistics
+  flag = ARKodePrintAllStats(arkode_mem, stdout, SUN_OUTPUTFORMAT_TABLE);
+  if (check_flag(flag, "ARKodePrintAllStats")) { return 1; }
+
+  // Clean up and return with successful completion
+  N_VDestroy(y);
+  ARKodeFree(&arkode_mem);
+
+  cout << "End ERKStep StageInfo test" << endl;
+
+  return 0;
+}
+
+// Callback functions
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step failure processing at t = "
+            << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << ")," << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-RHS processing (stage " << stage << " of " << max_stages
+            << ") at t = " << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << "), " << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-stage processing (stage " << stage << " of "
+            << max_stages << ") at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "), "
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+/*---- end of file ----*/
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_erkstep.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_erkstep.out
new file mode 100644
index 0000000000..f14856a4d7
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_erkstep.out
@@ -0,0 +1,64 @@
+Start ERKStep StageInfo test
+           t                        u                        v                      u err                    v err
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-RHS processing (stage 0 of 5) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 4.71e-08 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 2.06e-04 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Post-stage processing (stage 1 of 5) at t = 4.12e-05 (tn = 0.00e+00 , tcur = 4.12e-05), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 4.12e-05 (tn = 0.00e+00 , tcur = 4.12e-05), ||y||_2 = 2.1213203436e+00]
+    [Post-stage processing (stage 2 of 5) at t = 6.18e-05 (tn = 0.00e+00 , tcur = 6.18e-05), ||y||_2 = 2.1213200432e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 6.18e-05 (tn = 0.00e+00 , tcur = 6.18e-05), ||y||_2 = 2.1213200432e+00]
+    [Post-stage processing (stage 3 of 5) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213199340e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213199340e+00]
+    [Post-stage processing (stage 4 of 5) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04), ||y||_2 = 2.1213198430e+00]
+    [Post-step processing at t = 1.03e-04 (tn = 0.00e+00 , tcur = 1.03e-04),||y||_2 = 2.1213198430e+00]
+      1.0298602561e-04         1.2247448703e+00         1.7320501952e+00         2.2204460493e-16         0.0000000000e+00
+    [Pre-step processing at t = 1.03e-04 (tn = 1.03e-04 , tcur = 1.03e-04),||y||_2 = 2.1213198430e+00]
+    [Post-stage processing (stage 1 of 5) at t = 6.56e-03 (tn = 1.03e-04 , tcur = 6.56e-03), ||y||_2 = 2.1212571010e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.56e-03 (tn = 1.03e-04 , tcur = 6.56e-03), ||y||_2 = 2.1212571010e+00]
+    [Post-stage processing (stage 2 of 5) at t = 9.78e-03 (tn = 1.03e-04 , tcur = 9.78e-03), ||y||_2 = 2.1138657565e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 9.78e-03 (tn = 1.03e-04 , tcur = 9.78e-03), ||y||_2 = 2.1138657565e+00]
+    [Post-stage processing (stage 3 of 5) at t = 1.62e-02 (tn = 1.03e-04 , tcur = 1.62e-02), ||y||_2 = 2.1111621630e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.62e-02 (tn = 1.03e-04 , tcur = 1.62e-02), ||y||_2 = 2.1111621630e+00]
+    [Post-stage processing (stage 4 of 5) at t = 1.62e-02 (tn = 1.03e-04 , tcur = 1.62e-02), ||y||_2 = 2.1089486502e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.62e-02 (tn = 1.03e-04 , tcur = 1.62e-02), ||y||_2 = 2.1089486502e+00]
+    [Post-step failure processing at t = 1.62e-02 (tn = 1.03e-04 , tcur = 1.62e-02),||y||_2 = 2.1089486502e+00]
+    [Pre-step processing at t = 1.03e-04 (tn = 1.03e-04 , tcur = 1.03e-04),||y||_2 = 2.1213198430e+00]
+    [Post-stage processing (stage 1 of 5) at t = 6.49e-03 (tn = 1.03e-04 , tcur = 6.49e-03), ||y||_2 = 2.1212577772e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.49e-03 (tn = 1.03e-04 , tcur = 6.49e-03), ||y||_2 = 2.1212577772e+00]
+    [Post-stage processing (stage 2 of 5) at t = 9.68e-03 (tn = 1.03e-04 , tcur = 9.68e-03), ||y||_2 = 2.1140241446e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 9.68e-03 (tn = 1.03e-04 , tcur = 9.68e-03), ||y||_2 = 2.1140241446e+00]
+    [Post-stage processing (stage 3 of 5) at t = 1.61e-02 (tn = 1.03e-04 , tcur = 1.61e-02), ||y||_2 = 2.1113775352e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.61e-02 (tn = 1.03e-04 , tcur = 1.61e-02), ||y||_2 = 2.1113775352e+00]
+    [Post-stage processing (stage 4 of 5) at t = 1.61e-02 (tn = 1.03e-04 , tcur = 1.61e-02), ||y||_2 = 2.1092106860e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.61e-02 (tn = 1.03e-04 , tcur = 1.61e-02), ||y||_2 = 2.1092106860e+00]
+    [Post-step processing at t = 1.61e-02 (tn = 1.03e-04 , tcur = 1.61e-02),||y||_2 = 2.1092106860e+00]
+      1.6063645340e-02         1.2247184913e+00         1.7172170321e+00         4.4212199679e-08         2.9106373090e-08
+    [Pre-step processing at t = 1.61e-02 (tn = 1.61e-02 , tcur = 1.61e-02),||y||_2 = 2.1092106860e+00]
+    [Post-stage processing (stage 1 of 5) at t = 2.24e-02 (tn = 1.61e-02 , tcur = 2.24e-02), ||y||_2 = 2.0996520676e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.24e-02 (tn = 1.61e-02 , tcur = 2.24e-02), ||y||_2 = 2.0996520676e+00]
+    [Post-stage processing (stage 2 of 5) at t = 2.56e-02 (tn = 1.61e-02 , tcur = 2.56e-02), ||y||_2 = 2.0880076268e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.56e-02 (tn = 1.61e-02 , tcur = 2.56e-02), ||y||_2 = 2.0880076268e+00]
+    [Post-stage processing (stage 3 of 5) at t = 3.20e-02 (tn = 1.61e-02 , tcur = 3.20e-02), ||y||_2 = 2.0760211062e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.20e-02 (tn = 1.61e-02 , tcur = 3.20e-02), ||y||_2 = 2.0760211062e+00]
+    [Post-stage processing (stage 4 of 5) at t = 3.20e-02 (tn = 1.61e-02 , tcur = 3.20e-02), ||y||_2 = 2.0740200715e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 3.20e-02 (tn = 1.61e-02 , tcur = 3.20e-02), ||y||_2 = 2.0740200715e+00]
+    [Post-step processing at t = 3.20e-02 (tn = 1.61e-02 , tcur = 3.20e-02),||y||_2 = 2.0740200715e+00]
+      3.2023388180e-02         1.2246401240e+00         1.6738625462e+00         8.7464898657e-08         1.4947668547e-07
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.0320233881803733
+Steps                         = 3
+Step attempts                 = 4
+Stability limited steps       = 0
+Accuracy limited steps        = 4
+Error test fails              = 1
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.000102986025609508
+Last step size                = 0.0159597428408288
+Current step size             = 0.0166588795523219
+RHS fn evals                  = 19
+End ERKStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_forcingstep.cpp b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_forcingstep.cpp
new file mode 100644
index 0000000000..e5b6bf75d2
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_forcingstep.cpp
@@ -0,0 +1,296 @@
+/* -----------------------------------------------------------------------------
+ * Programmer(s): Daniel R. Reynolds @ UMBC
+ * -----------------------------------------------------------------------------
+ * SUNDIALS Copyright Start
+ * Copyright (c) 2025-2026, Lawrence Livermore National Security,
+ * University of Maryland Baltimore County, and the SUNDIALS contributors.
+ * Copyright (c) 2013-2025, Lawrence Livermore National Security
+ * and Southern Methodist University.
+ * Copyright (c) 2002-2013, Lawrence Livermore National Security.
+ * All rights reserved.
+ *
+ * See the top-level LICENSE and NOTICE files for details.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ * SUNDIALS Copyright End
+ * -----------------------------------------------------------------------------
+ * Test stage information and pre/postprocessing routines in ForcingStep
+ * ---------------------------------------------------------------------------*/
+
+#include <cmath>
+#include <cstdio>
+#include <iomanip>
+#include <iostream>
+#include <limits>
+
+// Include desired integrators and vectors
+#include "arkode/arkode_erkstep.h"
+#include "arkode/arkode_forcingstep.h"
+#include "nvector/nvector_serial.h"
+#include "sundials/sundials_context.hpp"
+
+#include "problems/estep.hpp"
+#include "utilities/check_return.hpp"
+
+using namespace std;
+using namespace problems::estep;
+
+// Store the main integrator global memory for these tests only, so that we
+// can call ARKodeGetLastTime etc in the step and stage pre/postprocessing
+// callback functions below.  This would normally be stored in user_data, but
+// here we reuse problem definitions from other tests.
+void* arkode_mem = nullptr;
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data);
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+
+int main(int argc, char* argv[])
+{
+  cout << "Start ForcingStep StageInfo test" << endl;
+
+  // SUNDIALS context object for this simulation
+  sundials::Context sunctx;
+
+  // Step sizes: overall, partition 1, partition 2
+  sunrealtype dt   = SUN_RCONST(0.001);
+  sunrealtype dt_1 = dt / 2;
+  sunrealtype dt_2 = dt / 4;
+
+  // Create initial condition
+  N_Vector y = N_VNew_Serial(1, sunctx);
+  if (check_ptr(y, "N_VNew_Serial")) { return 1; }
+
+  int flag = initial_condition(y);
+  if (check_flag(flag, "initial_condition")) { return 1; }
+
+  // Create partition 1 integrator
+  void* stepper_1 = ERKStepCreate(ode_rhs_1, zero, y, sunctx);
+  if (check_ptr(stepper_1, "ERKStepCreate")) { return 1; }
+
+  flag = ARKodeSetUserData(stepper_1, &problem_data);
+  if (check_flag(flag, "ARKodeSetUserData")) { return 1; }
+
+  flag = ARKodeSetFixedStep(stepper_1, dt_1);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  // Create partition 1 integrator
+  void* stepper_2 = ERKStepCreate(ode_rhs_2, zero, y, sunctx);
+  if (check_ptr(stepper_2, "ERKStepCreate")) { return 1; }
+
+  flag = ARKodeSetFixedStep(stepper_2, dt_2);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  // Create the overall integrator
+  SUNStepper steppers[2];
+
+  flag = ARKodeCreateSUNStepper(stepper_1, &steppers[0]);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  flag = ARKodeCreateSUNStepper(stepper_2, &steppers[1]);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  arkode_mem = ForcingStepCreate(steppers[0], steppers[1], zero, y, sunctx);
+  if (check_ptr(arkode_mem, "ForcingStepCreate")) { return 1; }
+
+  flag = ARKodeSetFixedStep(arkode_mem, dt);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  // Set pre/post step and stage routines
+  flag = ARKodeSetPreprocessStepFn(arkode_mem, preprocess_step);
+  if (check_flag(flag, "ARKodeSetPreprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFn(arkode_mem, postprocess_step);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFailFn(arkode_mem, postprocess_step_fail);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFailFn")) { return 1; }
+  flag = ARKodeSetPreprocessRHSFn(arkode_mem, preprocess_stage);
+  if (check_flag(flag, "ARKodeSetPreprocessRHSFn")) { return 1; }
+  flag = ARKodeSetPostprocessStageFn(arkode_mem, postprocess_stage);
+  if (check_flag(flag, "ARKodeSetPostprocessStageFn")) { return 1; }
+
+  // True solution vector
+  N_Vector yt = N_VClone(y);
+
+  flag = true_solution(zero, problem_data, yt);
+  if (check_flag(flag, "true_solution")) { return 1; }
+
+  // Initial time and fist output time
+  const sunrealtype dtout = one; // output interval
+  const int nout          = 3;   // number of outputs
+  sunrealtype tret        = zero;
+  sunrealtype tout        = tret + dtout;
+
+  const int width = numeric_limits<sunrealtype>::digits10 + 8;
+
+  // Output initial contion
+  cout << scientific;
+  cout << setprecision(numeric_limits<sunrealtype>::digits10);
+  cout << setw(width) << " t";
+  cout << setw(width) << " y";
+  cout << setw(width) << " y err" << endl;
+  for (int i = 0; i < 3 * width; i++) { cout << "-"; }
+  cout << endl;
+
+  sunrealtype* y_data  = N_VGetArrayPointer(y);
+  sunrealtype* yt_data = N_VGetArrayPointer(yt);
+
+  cout << setw(width) << tret << setw(width) << y_data[0] << setw(width)
+       << abs(y_data[0] - yt_data[0]) << endl;
+
+  // Advance in time
+  for (int i = 0; i < nout; i++)
+  {
+    flag = ARKodeEvolve(arkode_mem, tout, y, &tret, ARK_ONE_STEP);
+    if (check_flag(flag, "ARKodeEvolve")) { return 1; }
+
+    flag = true_solution(tret, problem_data, yt);
+    if (check_flag(flag, "true_solution")) { return 1; }
+
+    cout << setw(width) << tret << setw(width) << y_data[0] << setw(width)
+         << abs(y_data[0] - yt_data[0]) << endl;
+
+    // update output time
+    tout += dtout;
+  }
+  for (int i = 0; i < 3 * width; i++) { cout << "-"; }
+  cout << endl;
+
+  // Print some final statistics
+  flag = ARKodePrintAllStats(arkode_mem, stdout, SUN_OUTPUTFORMAT_TABLE);
+  if (check_flag(flag, "ARKodePrintAllStats")) { return 1; }
+
+  // Clean up and return with successful completion
+  N_VDestroy(y);
+  N_VDestroy(yt);
+  ARKodeFree(&arkode_mem);
+  ARKodeFree(&stepper_1);
+  ARKodeFree(&stepper_2);
+  SUNStepper_Destroy(&steppers[0]);
+  SUNStepper_Destroy(&steppers[1]);
+
+  cout << "End ForcingStep StageInfo test" << endl;
+
+  return 0;
+}
+
+// Callback functions
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step failure processing at t = "
+            << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << ")," << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-RHS processing (stage " << stage << " of " << max_stages
+            << ") at t = " << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << "), " << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-stage processing (stage " << stage << " of "
+            << max_stages << ") at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "), "
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+/*---- end of file ----*/
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_forcingstep.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_forcingstep.out
new file mode 100644
index 0000000000..c27dcd9965
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_forcingstep.out
@@ -0,0 +1,28 @@
+Start ForcingStep StageInfo test
+                      t                      y                  y err
+---------------------------------------------------------------------
+  0.000000000000000e+00  1.000000000000000e+00  0.000000000000000e+00
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 1.0000000000e+00]
+    [Post-step processing at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03),||y||_2 = 9.9900100033e-01]
+       1.0000000000e-03       9.9900100033e-01       9.9999966707e-07
+    [Pre-step processing at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03),||y||_2 = 9.9900100033e-01]
+    [Post-step processing at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03),||y||_2 = 9.9800200066e-01]
+       2.0000000000e-03       9.9800200066e-01       1.9979980046e-06
+    [Pre-step processing at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03),||y||_2 = 9.9800200066e-01]
+    [Post-step processing at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03),||y||_2 = 9.9700300299e-01]
+       3.0000000000e-03       9.9700300299e-01       2.9939930263e-06
+---------------------------------------------------------------------
+Current time                  = 0.003
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 0
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.001
+Last step size                = 0.001
+Current step size             = 0.001
+Partition 1 evolves           = 3
+Partition 2 evolves           = 3
+End ForcingStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep.cpp b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep.cpp
new file mode 100644
index 0000000000..17ee8ab6cc
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep.cpp
@@ -0,0 +1,305 @@
+/* -----------------------------------------------------------------------------
+ * Programmer(s): Daniel R. Reynolds @ UMBC
+ * -----------------------------------------------------------------------------
+ * SUNDIALS Copyright Start
+ * Copyright (c) 2025-2026, Lawrence Livermore National Security,
+ * University of Maryland Baltimore County, and the SUNDIALS contributors.
+ * Copyright (c) 2013-2025, Lawrence Livermore National Security
+ * and Southern Methodist University.
+ * Copyright (c) 2002-2013, Lawrence Livermore National Security.
+ * All rights reserved.
+ *
+ * See the top-level LICENSE and NOTICE files for details.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ * SUNDIALS Copyright End
+ * -----------------------------------------------------------------------------
+ * Test stage information and pre/postprocessing routines in LSRKStep
+ * ---------------------------------------------------------------------------*/
+
+#include <cmath>
+#include <cstdio>
+#include <iomanip>
+#include <iostream>
+#include <limits>
+
+// Include desired integrators, vectors, linear solvers, and nonlinear solvers
+#include "arkode/arkode_lsrkstep.h"
+#include "nvector/nvector_serial.h"
+
+#include "problems/prv.hpp"
+#include "sundials/sundials_nvector.h"
+#include "utilities/check_return.hpp"
+
+using namespace std;
+using namespace problems::prv;
+
+// Store the main integrator global memory for these tests only, so that we
+// can call ARKodeGetLastTime etc in the step and stage pre/postprocessing
+// callback functions below.  This would normally be stored in user_data, but
+// here we reuse problem definitions from other tests.
+void* arkode_mem = nullptr;
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data);
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+
+int main(int argc, char* argv[])
+{
+  cout << "Start LSRKStep StageInfo test" << endl;
+
+  // SUNDIALS context object for this simulation
+  sundials::Context sunctx;
+
+  // Use RKC (0), RKL (1), SSPs2 (2), SSPs3 (3), SSP43 (4), SSP104 (5)
+  int method = 0;
+  if (argc > 1) { method = stoi(argv[1]); }
+
+  // Create initial condition
+  N_Vector y = N_VNew_Serial(1, sunctx);
+  if (check_ptr(y, "N_VNew_Serial")) { return 1; }
+  N_VConst(true_solution(zero), y);
+
+  // Create LSRKStep memory structure
+  if (method < 2) { arkode_mem = LSRKStepCreateSTS(ode_rhs, zero, y, sunctx); }
+  else { arkode_mem = LSRKStepCreateSSP(ode_rhs, zero, y, sunctx); }
+  if (check_ptr(arkode_mem, "LSRKStepCreate")) { return 1; }
+
+  // Select method
+  int flag;
+  if (method == 0)
+  {
+    cout << "Using RKC method" << endl;
+    flag = LSRKStepSetSTSMethodByName(arkode_mem, "ARKODE_LSRK_RKC_2");
+  }
+  else if (method == 1)
+  {
+    cout << "Using RKL method" << endl;
+    flag = LSRKStepSetSTSMethodByName(arkode_mem, "ARKODE_LSRK_RKL_2");
+  }
+  else if (method == 2)
+  {
+    cout << "Using SSP(s,2) method" << endl;
+    flag = LSRKStepSetSSPMethodByName(arkode_mem, "ARKODE_LSRK_SSP_S_2");
+  }
+  else if (method == 3)
+  {
+    cout << "Using SSP(9,3) method" << endl;
+    flag = LSRKStepSetSSPMethodByName(arkode_mem, "ARKODE_LSRK_SSP_S_3");
+    if (flag == 0) { flag = LSRKStepSetNumSSPStages(arkode_mem, 4); }
+  }
+  else if (method == 4)
+  {
+    cout << "Using SSP(4,3) method" << endl;
+    flag = LSRKStepSetSSPMethodByName(arkode_mem, "ARKODE_LSRK_SSP_S_3");
+    if (flag == 0) { flag = LSRKStepSetNumSSPStages(arkode_mem, 4); }
+  }
+  else if (method == 5)
+  {
+    cout << "Using SSP(10,4) method" << endl;
+    flag = LSRKStepSetSSPMethodByName(arkode_mem, "ARKODE_LSRK_SSP_10_4");
+  }
+  else
+  {
+    cerr << "Invalid method option\n";
+    return 1;
+  }
+  if (check_flag(flag, "LSRKStepSetMethodByName")) { return 1; }
+
+  flag = ARKodeSetUserData(arkode_mem, &problem_data);
+  if (check_flag(flag, "ARKodeSetUserData")) { return 1; }
+
+  // Relative and absolute tolerances
+  const sunrealtype rtol = SUN_RCONST(1.0e-6);
+  const sunrealtype atol = SUN_RCONST(1.0e-10);
+
+  flag = ARKodeSStolerances(arkode_mem, rtol, atol);
+  if (check_flag(flag, "ARKodeSStolerances")) { return 1; }
+
+  // Specify dominant eigenvalue function
+  flag = LSRKStepSetDomEigFn(arkode_mem, ode_dom_eig);
+  if (check_flag(flag, "LSRKStepSetDomEigFn")) { return 1; }
+
+  // Set pre/post step and stage routines
+  flag = ARKodeSetPreprocessStepFn(arkode_mem, preprocess_step);
+  if (check_flag(flag, "ARKodeSetPreprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFn(arkode_mem, postprocess_step);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFailFn(arkode_mem, postprocess_step_fail);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFailFn")) { return 1; }
+  flag = ARKodeSetPreprocessRHSFn(arkode_mem, preprocess_stage);
+  if (check_flag(flag, "ARKodeSetPreprocessRHSFn")) { return 1; }
+  flag = ARKodeSetPostprocessStageFn(arkode_mem, postprocess_stage);
+  if (check_flag(flag, "ARKodeSetPostprocessStageFn")) { return 1; }
+
+  // Initial time and fist output time
+  const sunrealtype dtout = one; // output interval
+  const int nout          = 3;   // number of outputs
+  sunrealtype tret        = zero;
+  sunrealtype tout        = tret + dtout;
+
+  const int width = numeric_limits<sunrealtype>::digits10 + 8;
+
+  // Output initial contion
+  cout << scientific;
+  cout << setprecision(numeric_limits<sunrealtype>::digits10);
+  cout << setw(width) << " t";
+  cout << setw(width) << " y";
+  cout << setw(width) << " y err" << endl;
+  for (int i = 0; i < 3 * width; i++) { cout << "-"; }
+  cout << endl;
+
+  sunrealtype* y_data = N_VGetArrayPointer(y);
+
+  cout << setw(width) << tret << setw(width) << y_data[0] << setw(width)
+       << abs(y_data[0] - true_solution(tret)) << endl;
+
+  // Advance in time
+  for (int i = 0; i < nout; i++)
+  {
+    flag = ARKodeEvolve(arkode_mem, tout, y, &tret, ARK_ONE_STEP);
+    if (check_flag(flag, "ARKodeEvolve")) { return 1; }
+
+    cout << setw(width) << tret << setw(width) << y_data[0] << setw(width)
+         << abs(y_data[0] - true_solution(tret)) << endl;
+
+    // update output time
+    tout += dtout;
+  }
+  for (int i = 0; i < 3 * width; i++) { cout << "-"; }
+  cout << endl;
+
+  // Print some final statistics
+  flag = ARKodePrintAllStats(arkode_mem, stdout, SUN_OUTPUTFORMAT_TABLE);
+  if (check_flag(flag, "ARKodePrintAllStats")) { return 1; }
+
+  // Clean up and return with successful completion
+  N_VDestroy(y);
+  ARKodeFree(&arkode_mem);
+
+  cout << "End LSRKStep StageInfo test" << endl;
+
+  return 0;
+}
+
+// Callback functions
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step failure processing at t = "
+            << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << ")," << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-RHS processing (stage " << stage << " of " << max_stages
+            << ") at t = " << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << "), " << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-stage processing (stage " << stage << " of "
+            << max_stages << ") at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "), "
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+/*---- end of file ----*/
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_0.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_0.out
new file mode 100644
index 0000000000..de95754b54
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_0.out
@@ -0,0 +1,45 @@
+Start LSRKStep StageInfo test
+Using RKC method
+                      t                      y                  y err
+---------------------------------------------------------------------
+  0.000000000000000e+00  0.000000000000000e+00  0.000000000000000e+00
+    [Pre-RHS processing (stage 0 of 0) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 0.0000000000e+00]
+    [Pre-RHS processing (stage 0 of 0) at t = 1.49e-12 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.4901161194e-12]
+    [Pre-RHS processing (stage 0 of 0) at t = 1.22e-11 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.2207031250e-11]
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 0.0000000000e+00]
+    [Post-stage processing (stage 0 of 2) at t = 1.47e-12 (tn = 0.00e+00 , tcur = 1.47e-12), ||y||_2 = 1.4693648727e-12]
+    [Pre-RHS processing (stage 1 of 2) at t = 1.47e-12 (tn = 0.00e+00 , tcur = 1.47e-12), ||y||_2 = 1.4693648727e-12]
+    [Pre-RHS processing (stage 2 of 2) at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Post-step processing at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12),||y||_2 = 6.1035156250e-12]
+       6.1035156250e-12       6.1035156250e-12       1.2116903504e-26
+    [Pre-step processing at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12),||y||_2 = 6.1035156250e-12]
+    [Post-stage processing (stage 0 of 2) at t = 1.47e-08 (tn = 6.10e-12 , tcur = 1.47e-08), ||y||_2 = 1.4699752242e-08]
+    [Pre-RHS processing (stage 1 of 2) at t = 1.47e-08 (tn = 6.10e-12 , tcur = 1.47e-08), ||y||_2 = 1.4699752242e-08]
+    [Pre-RHS processing (stage 2 of 2) at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Post-step processing at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08),||y||_2 = 6.1041259766e-08]
+       6.1041259766e-08       6.1041259766e-08       5.2939559203e-22
+    [Pre-step processing at t = 6.10e-08 (tn = 6.10e-08 , tcur = 6.10e-08),||y||_2 = 6.1041259766e-08]
+    [Post-stage processing (stage 0 of 2) at t = 3.55e-07 (tn = 6.10e-08 , tcur = 3.55e-07), ||y||_2 = 3.5491423430e-07]
+    [Pre-RHS processing (stage 1 of 2) at t = 3.55e-07 (tn = 6.10e-08 , tcur = 3.55e-07), ||y||_2 = 3.5491423430e-07]
+    [Pre-RHS processing (stage 2 of 2) at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06), ||y||_2 = 1.2817443848e-06]
+    [Post-step processing at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06),||y||_2 = 1.2817443848e-06]
+       1.2817443848e-06       1.2817443848e-06       3.8518823276e-19
+---------------------------------------------------------------------
+Current time                  = 1.28174438476563e-06
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 3
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 6.103515625e-12
+Last step size                = 1.220703125e-06
+Current step size             = 2.44140625e-05
+RHS fn evals                  = 9
+Number of dom_eig updates     = 1
+Max. num. of stages used      = 2
+Max. num. of stages allowed   = 200
+Max. spectral radius          = 999.9
+Min. spectral radius          = 999.9
+End LSRKStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_1.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_1.out
new file mode 100644
index 0000000000..851b298a95
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_1.out
@@ -0,0 +1,45 @@
+Start LSRKStep StageInfo test
+Using RKL method
+                      t                      y                  y err
+---------------------------------------------------------------------
+  0.000000000000000e+00  0.000000000000000e+00  0.000000000000000e+00
+    [Pre-RHS processing (stage 0 of 0) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 0.0000000000e+00]
+    [Pre-RHS processing (stage 0 of 0) at t = 1.49e-12 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.4901161194e-12]
+    [Pre-RHS processing (stage 0 of 0) at t = 1.22e-11 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.2207031250e-11]
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 0.0000000000e+00]
+    [Post-stage processing (stage 0 of 2) at t = 2.03e-12 (tn = 0.00e+00 , tcur = 2.03e-12), ||y||_2 = 2.0345052083e-12]
+    [Pre-RHS processing (stage 1 of 2) at t = 2.03e-12 (tn = 0.00e+00 , tcur = 2.03e-12), ||y||_2 = 2.0345052083e-12]
+    [Pre-RHS processing (stage 2 of 2) at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Post-step processing at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12),||y||_2 = 6.1035156250e-12]
+       6.1035156250e-12       6.1035156250e-12       0.0000000000e+00
+    [Pre-step processing at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12),||y||_2 = 6.1035156250e-12]
+    [Post-stage processing (stage 0 of 2) at t = 2.04e-08 (tn = 6.10e-12 , tcur = 2.04e-08), ||y||_2 = 2.0351155599e-08]
+    [Pre-RHS processing (stage 1 of 2) at t = 2.04e-08 (tn = 6.10e-12 , tcur = 2.04e-08), ||y||_2 = 2.0351155599e-08]
+    [Pre-RHS processing (stage 2 of 2) at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Post-step processing at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08),||y||_2 = 6.1041259766e-08]
+       6.1041259766e-08       6.1041259766e-08       3.9704669403e-23
+    [Pre-step processing at t = 6.10e-08 (tn = 6.10e-08 , tcur = 6.10e-08),||y||_2 = 6.1041259766e-08]
+    [Post-stage processing (stage 0 of 2) at t = 4.68e-07 (tn = 6.10e-08 , tcur = 4.68e-07), ||y||_2 = 4.6794230143e-07]
+    [Pre-RHS processing (stage 1 of 2) at t = 4.68e-07 (tn = 6.10e-08 , tcur = 4.68e-07), ||y||_2 = 4.6794230143e-07]
+    [Pre-RHS processing (stage 2 of 2) at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06), ||y||_2 = 1.2817443848e-06]
+    [Post-step processing at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06),||y||_2 = 1.2817443848e-06]
+       1.2817443848e-06       1.2817443848e-06       3.0323779512e-19
+---------------------------------------------------------------------
+Current time                  = 1.28174438476563e-06
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 3
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 6.103515625e-12
+Last step size                = 1.220703125e-06
+Current step size             = 2.44140625e-05
+RHS fn evals                  = 9
+Number of dom_eig updates     = 1
+Max. num. of stages used      = 2
+Max. num. of stages allowed   = 200
+Max. spectral radius          = 999.9
+Min. spectral radius          = 999.9
+End LSRKStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_2.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_2.out
new file mode 100644
index 0000000000..97f718113c
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_2.out
@@ -0,0 +1,40 @@
+Start LSRKStep StageInfo test
+Using SSP(s,2) method
+                      t                      y                  y err
+---------------------------------------------------------------------
+  0.000000000000000e+00  0.000000000000000e+00  0.000000000000000e+00
+    [Pre-RHS processing (stage 0 of 2) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 0.0000000000e+00]
+    [Pre-RHS processing (stage 0 of 2) at t = 1.49e-12 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.4901161194e-12]
+    [Pre-RHS processing (stage 0 of 2) at t = 1.22e-11 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.2207031250e-11]
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 0.0000000000e+00]
+    [Post-stage processing (stage 0 of 2) at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Pre-RHS processing (stage 1 of 2) at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Post-step processing at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12),||y||_2 = 6.1035156250e-12]
+       6.1035156250e-12       6.1035156250e-12       0.0000000000e+00
+    [Pre-step processing at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12),||y||_2 = 6.1035156250e-12]
+    [Pre-RHS processing (stage 0 of 2) at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Post-stage processing (stage 0 of 2) at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Pre-RHS processing (stage 1 of 2) at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Post-step processing at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08),||y||_2 = 6.1041259766e-08]
+       6.1041259766e-08       6.1041259766e-08       3.9704669403e-23
+    [Pre-step processing at t = 6.10e-08 (tn = 6.10e-08 , tcur = 6.10e-08),||y||_2 = 6.1041259766e-08]
+    [Pre-RHS processing (stage 0 of 2) at t = 6.10e-08 (tn = 6.10e-08 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Post-stage processing (stage 0 of 2) at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06), ||y||_2 = 1.2817443848e-06]
+    [Pre-RHS processing (stage 1 of 2) at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06), ||y||_2 = 1.2817443848e-06]
+    [Post-step processing at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06),||y||_2 = 1.2817443848e-06]
+       1.2817443848e-06       1.2817443848e-06       3.0366131159e-19
+---------------------------------------------------------------------
+Current time                  = 1.28174438476563e-06
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 3
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 6.103515625e-12
+Last step size                = 1.220703125e-06
+Current step size             = 2.44140625e-05
+RHS fn evals                  = 8
+Number of stages used         = 2
+End LSRKStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_3.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_3.out
new file mode 100644
index 0000000000..37f0e8cb88
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_3.out
@@ -0,0 +1,58 @@
+Start LSRKStep StageInfo test
+Using SSP(s,3) method
+                      t                      y                  y err
+---------------------------------------------------------------------
+  0.000000000000000e+00  0.000000000000000e+00  0.000000000000000e+00
+    [Pre-RHS processing (stage 0 of 4) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 0.0000000000e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 1.49e-12 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.4901161194e-12]
+    [Pre-RHS processing (stage 0 of 4) at t = 1.22e-11 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.2207031250e-11]
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 0.0000000000e+00]
+    [Post-stage processing (stage 0 of 4) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 3.0517578125e-12]
+    [Pre-RHS processing (stage 0 of 4) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 3.0517578125e-12]
+    [Post-stage processing (stage 0 of 4) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 6.1035156158e-12]
+    [Pre-RHS processing (stage 1 of 4) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 6.1035156158e-12]
+    [Post-stage processing (stage 1 of 4) at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12), ||y||_2 = 9.1552734191e-12]
+    [Pre-RHS processing (stage 2 of 4) at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12), ||y||_2 = 9.1552734191e-12]
+    [Post-stage processing (stage 2 of 4) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 6.1035156158e-12]
+    [Pre-RHS processing (stage 3 of 4) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 6.1035156158e-12]
+    [Post-step processing at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12),||y||_2 = 9.1552734191e-12]
+       6.1035156250e-12       9.1552734191e-12       3.0517577941e-12
+    [Pre-step processing at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12),||y||_2 = 9.1552734191e-12]
+    [Pre-RHS processing (stage 0 of 4) at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12), ||y||_2 = 9.1552734191e-12]
+    [Post-stage processing (stage 0 of 4) at t = 1.72e-11 (tn = 6.10e-12 , tcur = 1.72e-11), ||y||_2 = 2.0228798238e-11]
+    [Pre-RHS processing (stage 0 of 4) at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12), ||y||_2 = 2.0228798238e-11]
+    [Post-stage processing (stage 0 of 4) at t = 1.72e-11 (tn = 6.10e-12 , tcur = 1.72e-11), ||y||_2 = 3.1302322936e-11]
+    [Pre-RHS processing (stage 1 of 4) at t = 1.72e-11 (tn = 6.10e-12 , tcur = 1.72e-11), ||y||_2 = 3.1302322936e-11]
+    [Post-stage processing (stage 1 of 4) at t = 2.83e-11 (tn = 6.10e-12 , tcur = 2.83e-11), ||y||_2 = 4.2375847634e-11]
+    [Pre-RHS processing (stage 2 of 4) at t = 2.83e-11 (tn = 6.10e-12 , tcur = 2.83e-11), ||y||_2 = 4.2375847634e-11]
+    [Post-stage processing (stage 2 of 4) at t = 1.72e-11 (tn = 6.10e-12 , tcur = 1.72e-11), ||y||_2 = 3.1302322936e-11]
+    [Pre-RHS processing (stage 3 of 4) at t = 1.72e-11 (tn = 6.10e-12 , tcur = 1.72e-11), ||y||_2 = 3.1302322936e-11]
+    [Post-step processing at t = 2.83e-11 (tn = 6.10e-12 , tcur = 2.83e-11),||y||_2 = 4.2375847634e-11]
+       2.8250565330e-11       4.2375847634e-11       1.4125282303e-11
+    [Pre-step processing at t = 2.83e-11 (tn = 2.83e-11 , tcur = 2.83e-11),||y||_2 = 4.2375847634e-11]
+    [Pre-RHS processing (stage 0 of 4) at t = 2.83e-11 (tn = 2.83e-11 , tcur = 2.83e-11), ||y||_2 = 4.2375847634e-11]
+    [Post-stage processing (stage 0 of 4) at t = 5.44e-11 (tn = 2.83e-11 , tcur = 5.44e-11), ||y||_2 = 6.8524126345e-11]
+    [Pre-RHS processing (stage 0 of 4) at t = 2.83e-11 (tn = 2.83e-11 , tcur = 2.83e-11), ||y||_2 = 6.8524126345e-11]
+    [Post-stage processing (stage 0 of 4) at t = 5.44e-11 (tn = 2.83e-11 , tcur = 5.44e-11), ||y||_2 = 9.4672404379e-11]
+    [Pre-RHS processing (stage 1 of 4) at t = 5.44e-11 (tn = 2.83e-11 , tcur = 5.44e-11), ||y||_2 = 9.4672404379e-11]
+    [Post-stage processing (stage 1 of 4) at t = 8.05e-11 (tn = 2.83e-11 , tcur = 8.05e-11), ||y||_2 = 1.2082068241e-10]
+    [Pre-RHS processing (stage 2 of 4) at t = 8.05e-11 (tn = 2.83e-11 , tcur = 8.05e-11), ||y||_2 = 1.2082068241e-10]
+    [Post-stage processing (stage 2 of 4) at t = 5.44e-11 (tn = 2.83e-11 , tcur = 5.44e-11), ||y||_2 = 9.4672404379e-11]
+    [Pre-RHS processing (stage 3 of 4) at t = 5.44e-11 (tn = 2.83e-11 , tcur = 5.44e-11), ||y||_2 = 9.4672404379e-11]
+    [Post-step processing at t = 8.05e-11 (tn = 2.83e-11 , tcur = 8.05e-11),||y||_2 = 1.2082068241e-10]
+       8.0547123483e-11       1.2082068241e-10       4.0273558929e-11
+---------------------------------------------------------------------
+Current time                  = 8.05471234832829e-11
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 3
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 6.103515625e-12
+Last step size                = 5.22965581530996e-11
+Current step size             = 9.27352060660382e-11
+RHS fn evals                  = 17
+Number of stages used         = 4
+End LSRKStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_4.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_4.out
new file mode 100644
index 0000000000..e802bfd349
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_4.out
@@ -0,0 +1,52 @@
+Start LSRKStep StageInfo test
+Using SSP(4,3) method
+                      t                      y                  y err
+---------------------------------------------------------------------
+  0.000000000000000e+00  0.000000000000000e+00  0.000000000000000e+00
+    [Pre-RHS processing (stage 0 of 4) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 0.0000000000e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 1.49e-12 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.4901161194e-12]
+    [Pre-RHS processing (stage 0 of 4) at t = 1.22e-11 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.2207031250e-11]
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 0.0000000000e+00]
+    [Post-stage processing (stage 0 of 4) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 3.0517578125e-12]
+    [Pre-RHS processing (stage 1 of 4) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 3.0517578125e-12]
+    [Post-stage processing (stage 1 of 4) at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Pre-RHS processing (stage 2 of 4) at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Post-stage processing (stage 2 of 4) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 3.0517578125e-12]
+    [Pre-RHS processing (stage 3 of 4) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 3.0517578125e-12]
+    [Post-step processing at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12),||y||_2 = 6.1035156250e-12]
+       6.1035156250e-12       6.1035156250e-12       8.0779356695e-28
+    [Pre-step processing at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12),||y||_2 = 6.1035156250e-12]
+    [Pre-RHS processing (stage 0 of 4) at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Post-stage processing (stage 0 of 4) at t = 3.05e-08 (tn = 6.10e-12 , tcur = 3.05e-08), ||y||_2 = 3.0523681641e-08]
+    [Pre-RHS processing (stage 1 of 4) at t = 3.05e-08 (tn = 6.10e-12 , tcur = 3.05e-08), ||y||_2 = 3.0523681641e-08]
+    [Post-stage processing (stage 1 of 4) at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Pre-RHS processing (stage 2 of 4) at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Post-stage processing (stage 2 of 4) at t = 3.05e-08 (tn = 6.10e-12 , tcur = 3.05e-08), ||y||_2 = 3.0523681641e-08]
+    [Pre-RHS processing (stage 3 of 4) at t = 3.05e-08 (tn = 6.10e-12 , tcur = 3.05e-08), ||y||_2 = 3.0523681641e-08]
+    [Post-step processing at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08),||y||_2 = 6.1041259766e-08]
+       6.1041259766e-08       6.1041259766e-08       0.0000000000e+00
+    [Pre-step processing at t = 6.10e-08 (tn = 6.10e-08 , tcur = 6.10e-08),||y||_2 = 6.1041259766e-08]
+    [Pre-RHS processing (stage 0 of 4) at t = 6.10e-08 (tn = 6.10e-08 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Post-stage processing (stage 0 of 4) at t = 6.71e-07 (tn = 6.10e-08 , tcur = 6.71e-07), ||y||_2 = 6.7139282227e-07]
+    [Pre-RHS processing (stage 1 of 4) at t = 6.71e-07 (tn = 6.10e-08 , tcur = 6.71e-07), ||y||_2 = 6.7139282227e-07]
+    [Post-stage processing (stage 1 of 4) at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06), ||y||_2 = 1.2817443848e-06]
+    [Pre-RHS processing (stage 2 of 4) at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06), ||y||_2 = 1.2817443848e-06]
+    [Post-stage processing (stage 2 of 4) at t = 6.71e-07 (tn = 6.10e-08 , tcur = 6.71e-07), ||y||_2 = 6.7139282227e-07]
+    [Pre-RHS processing (stage 3 of 4) at t = 6.71e-07 (tn = 6.10e-08 , tcur = 6.71e-07), ||y||_2 = 6.7139282227e-07]
+    [Post-step processing at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06),||y||_2 = 1.2817443848e-06]
+       1.2817443848e-06       1.2817443848e-06       2.1175823681e-22
+---------------------------------------------------------------------
+Current time                  = 1.28174438476563e-06
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 3
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 6.103515625e-12
+Last step size                = 1.220703125e-06
+Current step size             = 2.44140625e-05
+RHS fn evals                  = 14
+Number of stages used         = 4
+End LSRKStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_5.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_5.out
new file mode 100644
index 0000000000..7239080362
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_lsrkstep_5.out
@@ -0,0 +1,91 @@
+Start LSRKStep StageInfo test
+Using SSP(10,4) method
+                      t                      y                  y err
+---------------------------------------------------------------------
+  0.000000000000000e+00  0.000000000000000e+00  0.000000000000000e+00
+    [Pre-RHS processing (stage 0 of 10) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 0.0000000000e+00]
+    [Pre-RHS processing (stage 0 of 10) at t = 1.49e-12 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.4901161194e-12]
+    [Pre-RHS processing (stage 0 of 10) at t = 1.22e-11 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 1.2207031250e-11]
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 0.0000000000e+00]
+    [Post-stage processing (stage 0 of 10) at t = 1.02e-12 (tn = 0.00e+00 , tcur = 1.02e-12), ||y||_2 = 1.0172526042e-12]
+    [Pre-RHS processing (stage 1 of 10) at t = 1.02e-12 (tn = 0.00e+00 , tcur = 1.02e-12), ||y||_2 = 1.0172526042e-12]
+    [Post-stage processing (stage 1 of 10) at t = 2.03e-12 (tn = 0.00e+00 , tcur = 2.03e-12), ||y||_2 = 2.0345052083e-12]
+    [Pre-RHS processing (stage 2 of 10) at t = 2.03e-12 (tn = 0.00e+00 , tcur = 2.03e-12), ||y||_2 = 2.0345052083e-12]
+    [Post-stage processing (stage 2 of 10) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 3.0517578125e-12]
+    [Pre-RHS processing (stage 3 of 10) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 3.0517578125e-12]
+    [Post-stage processing (stage 3 of 10) at t = 4.07e-12 (tn = 0.00e+00 , tcur = 4.07e-12), ||y||_2 = 4.0690104167e-12]
+    [Pre-RHS processing (stage 4 of 10) at t = 4.07e-12 (tn = 0.00e+00 , tcur = 4.07e-12), ||y||_2 = 4.0690104167e-12]
+    [Post-stage processing (stage 4 of 10) at t = 5.09e-12 (tn = 0.00e+00 , tcur = 5.09e-12), ||y||_2 = 5.0862630208e-12]
+    [Post-stage processing (stage 4 of 10) at t = 2.03e-12 (tn = 0.00e+00 , tcur = 2.03e-12), ||y||_2 = 2.0345052083e-12]
+    [Pre-RHS processing (stage 5 of 10) at t = 2.03e-12 (tn = 0.00e+00 , tcur = 2.03e-12), ||y||_2 = 2.0345052083e-12]
+    [Post-stage processing (stage 5 of 10) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 3.0517578125e-12]
+    [Pre-RHS processing (stage 6 of 10) at t = 3.05e-12 (tn = 0.00e+00 , tcur = 3.05e-12), ||y||_2 = 3.0517578125e-12]
+    [Post-stage processing (stage 6 of 10) at t = 4.07e-12 (tn = 0.00e+00 , tcur = 4.07e-12), ||y||_2 = 4.0690104167e-12]
+    [Pre-RHS processing (stage 7 of 10) at t = 4.07e-12 (tn = 0.00e+00 , tcur = 4.07e-12), ||y||_2 = 4.0690104167e-12]
+    [Post-stage processing (stage 7 of 10) at t = 5.09e-12 (tn = 0.00e+00 , tcur = 5.09e-12), ||y||_2 = 5.0862630208e-12]
+    [Pre-RHS processing (stage 8 of 10) at t = 5.09e-12 (tn = 0.00e+00 , tcur = 5.09e-12), ||y||_2 = 5.0862630208e-12]
+    [Post-stage processing (stage 8 of 10) at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Pre-RHS processing (stage 9 of 10) at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Post-step processing at t = 6.10e-12 (tn = 0.00e+00 , tcur = 6.10e-12),||y||_2 = 6.1035156250e-12]
+       6.1035156250e-12       6.1035156250e-12       8.0779356695e-28
+    [Pre-step processing at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12),||y||_2 = 6.1035156250e-12]
+    [Pre-RHS processing (stage 0 of 10) at t = 6.10e-12 (tn = 6.10e-12 , tcur = 6.10e-12), ||y||_2 = 6.1035156250e-12]
+    [Post-stage processing (stage 0 of 10) at t = 1.02e-08 (tn = 6.10e-12 , tcur = 1.02e-08), ||y||_2 = 1.0178629557e-08]
+    [Pre-RHS processing (stage 1 of 10) at t = 1.02e-08 (tn = 6.10e-12 , tcur = 1.02e-08), ||y||_2 = 1.0178629557e-08]
+    [Post-stage processing (stage 1 of 10) at t = 2.04e-08 (tn = 6.10e-12 , tcur = 2.04e-08), ||y||_2 = 2.0351155599e-08]
+    [Pre-RHS processing (stage 2 of 10) at t = 2.04e-08 (tn = 6.10e-12 , tcur = 2.04e-08), ||y||_2 = 2.0351155599e-08]
+    [Post-stage processing (stage 2 of 10) at t = 3.05e-08 (tn = 6.10e-12 , tcur = 3.05e-08), ||y||_2 = 3.0523681641e-08]
+    [Pre-RHS processing (stage 3 of 10) at t = 3.05e-08 (tn = 6.10e-12 , tcur = 3.05e-08), ||y||_2 = 3.0523681641e-08]
+    [Post-stage processing (stage 3 of 10) at t = 4.07e-08 (tn = 6.10e-12 , tcur = 4.07e-08), ||y||_2 = 4.0696207682e-08]
+    [Pre-RHS processing (stage 4 of 10) at t = 4.07e-08 (tn = 6.10e-12 , tcur = 4.07e-08), ||y||_2 = 4.0696207682e-08]
+    [Post-stage processing (stage 4 of 10) at t = 5.09e-08 (tn = 6.10e-12 , tcur = 5.09e-08), ||y||_2 = 5.0868733724e-08]
+    [Post-stage processing (stage 4 of 10) at t = 2.04e-08 (tn = 6.10e-12 , tcur = 2.04e-08), ||y||_2 = 2.0351155599e-08]
+    [Pre-RHS processing (stage 5 of 10) at t = 2.04e-08 (tn = 6.10e-12 , tcur = 2.04e-08), ||y||_2 = 2.0351155599e-08]
+    [Post-stage processing (stage 5 of 10) at t = 3.05e-08 (tn = 6.10e-12 , tcur = 3.05e-08), ||y||_2 = 3.0523681641e-08]
+    [Pre-RHS processing (stage 6 of 10) at t = 3.05e-08 (tn = 6.10e-12 , tcur = 3.05e-08), ||y||_2 = 3.0523681641e-08]
+    [Post-stage processing (stage 6 of 10) at t = 4.07e-08 (tn = 6.10e-12 , tcur = 4.07e-08), ||y||_2 = 4.0696207682e-08]
+    [Pre-RHS processing (stage 7 of 10) at t = 4.07e-08 (tn = 6.10e-12 , tcur = 4.07e-08), ||y||_2 = 4.0696207682e-08]
+    [Post-stage processing (stage 7 of 10) at t = 5.09e-08 (tn = 6.10e-12 , tcur = 5.09e-08), ||y||_2 = 5.0868733724e-08]
+    [Pre-RHS processing (stage 8 of 10) at t = 5.09e-08 (tn = 6.10e-12 , tcur = 5.09e-08), ||y||_2 = 5.0868733724e-08]
+    [Post-stage processing (stage 8 of 10) at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Pre-RHS processing (stage 9 of 10) at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Post-step processing at t = 6.10e-08 (tn = 6.10e-12 , tcur = 6.10e-08),||y||_2 = 6.1041259766e-08]
+       6.1041259766e-08       6.1041259766e-08       0.0000000000e+00
+    [Pre-step processing at t = 6.10e-08 (tn = 6.10e-08 , tcur = 6.10e-08),||y||_2 = 6.1041259766e-08]
+    [Pre-RHS processing (stage 0 of 10) at t = 6.10e-08 (tn = 6.10e-08 , tcur = 6.10e-08), ||y||_2 = 6.1041259766e-08]
+    [Post-stage processing (stage 0 of 10) at t = 2.64e-07 (tn = 6.10e-08 , tcur = 2.64e-07), ||y||_2 = 2.6449178060e-07]
+    [Pre-RHS processing (stage 1 of 10) at t = 2.64e-07 (tn = 6.10e-08 , tcur = 2.64e-07), ||y||_2 = 2.6449178060e-07]
+    [Post-stage processing (stage 1 of 10) at t = 4.68e-07 (tn = 6.10e-08 , tcur = 4.68e-07), ||y||_2 = 4.6794230143e-07]
+    [Pre-RHS processing (stage 2 of 10) at t = 4.68e-07 (tn = 6.10e-08 , tcur = 4.68e-07), ||y||_2 = 4.6794230143e-07]
+    [Post-stage processing (stage 2 of 10) at t = 6.71e-07 (tn = 6.10e-08 , tcur = 6.71e-07), ||y||_2 = 6.7139282227e-07]
+    [Pre-RHS processing (stage 3 of 10) at t = 6.71e-07 (tn = 6.10e-08 , tcur = 6.71e-07), ||y||_2 = 6.7139282227e-07]
+    [Post-stage processing (stage 3 of 10) at t = 8.75e-07 (tn = 6.10e-08 , tcur = 8.75e-07), ||y||_2 = 8.7484334310e-07]
+    [Pre-RHS processing (stage 4 of 10) at t = 8.75e-07 (tn = 6.10e-08 , tcur = 8.75e-07), ||y||_2 = 8.7484334310e-07]
+    [Post-stage processing (stage 4 of 10) at t = 1.08e-06 (tn = 6.10e-08 , tcur = 1.08e-06), ||y||_2 = 1.0782938639e-06]
+    [Post-stage processing (stage 4 of 10) at t = 4.68e-07 (tn = 6.10e-08 , tcur = 4.68e-07), ||y||_2 = 4.6794230143e-07]
+    [Pre-RHS processing (stage 5 of 10) at t = 4.68e-07 (tn = 6.10e-08 , tcur = 4.68e-07), ||y||_2 = 4.6794230143e-07]
+    [Post-stage processing (stage 5 of 10) at t = 6.71e-07 (tn = 6.10e-08 , tcur = 6.71e-07), ||y||_2 = 6.7139282227e-07]
+    [Pre-RHS processing (stage 6 of 10) at t = 6.71e-07 (tn = 6.10e-08 , tcur = 6.71e-07), ||y||_2 = 6.7139282227e-07]
+    [Post-stage processing (stage 6 of 10) at t = 8.75e-07 (tn = 6.10e-08 , tcur = 8.75e-07), ||y||_2 = 8.7484334310e-07]
+    [Pre-RHS processing (stage 7 of 10) at t = 8.75e-07 (tn = 6.10e-08 , tcur = 8.75e-07), ||y||_2 = 8.7484334310e-07]
+    [Post-stage processing (stage 7 of 10) at t = 1.08e-06 (tn = 6.10e-08 , tcur = 1.08e-06), ||y||_2 = 1.0782938639e-06]
+    [Pre-RHS processing (stage 8 of 10) at t = 1.08e-06 (tn = 6.10e-08 , tcur = 1.08e-06), ||y||_2 = 1.0782938639e-06]
+    [Post-stage processing (stage 8 of 10) at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06), ||y||_2 = 1.2817443848e-06]
+    [Pre-RHS processing (stage 9 of 10) at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06), ||y||_2 = 1.2817443848e-06]
+    [Post-step processing at t = 1.28e-06 (tn = 6.10e-08 , tcur = 1.28e-06),||y||_2 = 1.2817443848e-06]
+       1.2817443848e-06       1.2817443848e-06       8.4703294725e-22
+---------------------------------------------------------------------
+Current time                  = 1.28174438476563e-06
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 3
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 6.103515625e-12
+Last step size                = 1.220703125e-06
+Current step size             = 2.44140625e-05
+RHS fn evals                  = 32
+Number of stages used         = 10
+End LSRKStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep.cpp b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep.cpp
new file mode 100644
index 0000000000..25791660d3
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep.cpp
@@ -0,0 +1,389 @@
+/* -----------------------------------------------------------------------------
+ * Programmer(s): Daniel R. Reynolds @ UMBC
+ * -----------------------------------------------------------------------------
+ * SUNDIALS Copyright Start
+ * Copyright (c) 2025-2026, Lawrence Livermore National Security,
+ * University of Maryland Baltimore County, and the SUNDIALS contributors.
+ * Copyright (c) 2013-2025, Lawrence Livermore National Security
+ * and Southern Methodist University.
+ * Copyright (c) 2002-2013, Lawrence Livermore National Security.
+ * All rights reserved.
+ *
+ * See the top-level LICENSE and NOTICE files for details.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ * SUNDIALS Copyright End
+ * -----------------------------------------------------------------------------
+ * Test stage information and pre/postprocessing routines in MRIStep
+ * ---------------------------------------------------------------------------*/
+
+#include <cmath>
+#include <cstdio>
+#include <iomanip>
+#include <iostream>
+#include <limits>
+
+// Include desired integrators, vectors, linear solvers, and nonlinear solvers
+#include "arkode/arkode.h"
+#include "arkode/arkode_arkstep.h"
+#include "arkode/arkode_mristep.h"
+#include "nvector/nvector_serial.h"
+#include "sundials/sundials_context.hpp"
+#include "sundials/sundials_iterative.h"
+#include "sundials/sundials_matrix.h"
+#include "sunlinsol/sunlinsol_spgmr.h"
+
+#include "problems/kpr.hpp"
+#include "utilities/check_return.hpp"
+
+using namespace std;
+using namespace problems::kpr;
+
+// Store the main integrator global memory for these tests only, so that we
+// can call ARKodeGetLastTime etc in the step and stage pre/postprocessing
+// callback functions below.  This would normally be stored in user_data, but
+// here we reuse problem definitions from other tests.
+void* arkode_mem = nullptr;
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data);
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+
+int main(int argc, char* argv[])
+{
+  cout << "Start MRIStep StageInfo test" << endl;
+
+  // SUNDIALS context object for this simulation
+  sundials::Context sunctx;
+
+  // Method to use:
+  //   0 = Ex-MRI-GARK
+  //   1 = Im-MRI-GARK
+  //   2 = ImEx-MRI-GARK
+  //   3 = Ex-MRI-SR
+  //   4 = Im-MRI-SR
+  //   5 = ImEx-MRI-SR
+  //   6 = MERK
+  int method_type = 0;
+  if (argc > 1) { method_type = stoi(argv[1]); }
+
+  // Create initial condition
+  N_Vector y = N_VNew_Serial(2, sunctx);
+  if (check_ptr(y, "N_VNew_Serial")) { return 1; }
+
+  sunrealtype utrue, vtrue;
+  int flag = true_sol(zero, &utrue, &vtrue);
+  if (check_flag(flag, "true_sol")) { return 1; }
+
+  sunrealtype* ydata = N_VGetArrayPointer(y);
+  ydata[0]           = utrue;
+  ydata[1]           = vtrue;
+
+  // Create fast stepper
+  void* inner_arkode_mem = ARKStepCreate(ode_rhs_ff, nullptr, zero, y, sunctx);
+  if (check_ptr(inner_arkode_mem, "ARKStepCreate")) { return 1; }
+
+  flag = ARKodeSetUserData(inner_arkode_mem, &problem_data);
+  if (check_flag(flag, "ARKodeSetUserData")) { return 1; }
+
+  // Relative and absolute tolerances
+  const sunrealtype inner_rtol = SUN_RCONST(1.0e-6);
+  const sunrealtype inner_atol = SUN_RCONST(1.0e-10);
+
+  flag = ARKodeSStolerances(inner_arkode_mem, inner_rtol, inner_atol);
+  if (check_flag(flag, "ARKodeSStolerances")) { return 1; }
+
+  MRIStepInnerStepper stepper = nullptr;
+  flag = ARKStepCreateMRIStepInnerStepper(inner_arkode_mem, &stepper);
+  if (check_flag(flag, "ARKStepCreateMRIStepInnerStepper")) { return 1; }
+
+  // Create MRIStep memory structure
+  if (method_type == 0)
+  {
+    cout << "Using Ex-MRI-GARK method" << endl;
+    arkode_mem = MRIStepCreate(ode_rhs_s, nullptr, zero, y, stepper, sunctx);
+    if (check_ptr(arkode_mem, "MRIStepCreate")) { return 1; }
+  }
+  else if (method_type == 1)
+  {
+    cout << "Using Im-MRI-GARK method" << endl;
+    arkode_mem = MRIStepCreate(nullptr, ode_rhs_s, zero, y, stepper, sunctx);
+    if (check_ptr(arkode_mem, "MRIStepCreate")) { return 1; }
+  }
+  else if (method_type == 2)
+  {
+    cout << "Using ImEx-MRI-GARK method" << endl;
+    arkode_mem = MRIStepCreate(ode_rhs_se, ode_rhs_si, zero, y, stepper, sunctx);
+    if (check_ptr(arkode_mem, "MRIStepCreate")) { return 1; }
+  }
+  else if (method_type == 3)
+  {
+    cout << "Using Ex-MRI-SR method" << endl;
+    arkode_mem = MRIStepCreate(ode_rhs_s, nullptr, zero, y, stepper, sunctx);
+    if (check_ptr(arkode_mem, "MRIStepCreate")) { return 1; }
+  }
+  else if (method_type == 4)
+  {
+    cout << "Using Im-MRI-SR method" << endl;
+    arkode_mem = MRIStepCreate(nullptr, ode_rhs_s, zero, y, stepper, sunctx);
+    if (check_ptr(arkode_mem, "MRIStepCreate")) { return 1; }
+  }
+  else if (method_type == 5)
+  {
+    cout << "Using ImEx-MRI-SR method" << endl;
+    arkode_mem = MRIStepCreate(ode_rhs_se, ode_rhs_si, zero, y, stepper, sunctx);
+    if (check_ptr(arkode_mem, "MRIStepCreate")) { return 1; }
+  }
+  else if (method_type == 6)
+  {
+    cout << "Using MERK method" << endl;
+    arkode_mem = MRIStepCreate(ode_rhs_s, nullptr, zero, y, stepper, sunctx);
+    if (check_ptr(arkode_mem, "MRIStepCreate")) { return 1; }
+  }
+  else
+  {
+    cerr << "ERROR: Invalid method type option " << method_type;
+    return 1;
+  }
+
+  // Set MRI-SR or MERK method
+  MRIStepCoupling C = nullptr;
+  if (method_type == 3 || method_type == 4 || method_type == 5)
+  {
+    C = MRIStepCoupling_LoadTable(ARKODE_IMEX_MRI_SR32);
+    if (check_ptr(C, "MRIStepCoupling_LoadTable")) { return 1; }
+  }
+  else if (method_type == 6)
+  {
+    C = MRIStepCoupling_LoadTable(ARKODE_MERK32);
+    if (check_ptr(C, "MRIStepCoupling_LoadTable")) { return 1; }
+  }
+
+  if (C)
+  {
+    flag = MRIStepSetCoupling(arkode_mem, C);
+    if (check_flag(flag, "MRIStepSetCoupling")) { return 1; }
+    MRIStepCoupling_Free(C);
+  }
+
+  flag = ARKodeSetUserData(arkode_mem, &problem_data);
+  if (check_flag(flag, "ARKodeSetUserData")) { return 1; }
+
+  // Relative and absolute tolerances
+  const sunrealtype rtol = SUN_RCONST(1.0e-6);
+  const sunrealtype atol = SUN_RCONST(1.0e-10);
+
+  flag = ARKodeSStolerances(arkode_mem, rtol, atol);
+  if (check_flag(flag, "ARKodeSStolerances")) { return 1; }
+
+  // Set the slow step size
+  const sunrealtype hfixed = SUN_RCONST(0.001);
+
+  flag = ARKodeSetFixedStep(arkode_mem, hfixed);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  SUNMatrix A        = nullptr;
+  SUNLinearSolver LS = nullptr;
+
+  if (method_type == 1 || method_type == 2 || method_type == 4 || method_type == 5)
+  {
+    cout << "Using Newton nonlinear solver" << endl;
+    cout << "Using GMRES iterative linear solver" << endl;
+
+    LS = SUNLinSol_SPGMR(y, SUN_PREC_NONE, 0, sunctx);
+    if (check_ptr(LS, "SUNLinSol_SPGMR")) { return 1; }
+
+    flag = ARKodeSetLinearSolver(arkode_mem, LS, A);
+    if (check_flag(flag, "ARKodeSetLinearSolver")) { return 1; }
+  }
+
+  // Set pre/post step and stage routines
+  flag = ARKodeSetPreprocessStepFn(arkode_mem, preprocess_step);
+  if (check_flag(flag, "ARKodeSetPreprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFn(arkode_mem, postprocess_step);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFailFn(arkode_mem, postprocess_step_fail);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFailFn")) { return 1; }
+  flag = ARKodeSetPreprocessRHSFn(arkode_mem, preprocess_stage);
+  if (check_flag(flag, "ARKodeSetPreprocessRHSFn")) { return 1; }
+  flag = ARKodeSetPostprocessStageFn(arkode_mem, postprocess_stage);
+  if (check_flag(flag, "ARKodeSetPostprocessStageFn")) { return 1; }
+
+  // Initial time and fist output time
+  const sunrealtype dtout = one; // output interval
+  const int nout          = 3;   // number of outputs
+  sunrealtype tret        = zero;
+  sunrealtype tout        = tret + dtout;
+
+  // Output initial contion
+  cout << scientific;
+  cout << setprecision(numeric_limits<sunrealtype>::digits10);
+  cout << "           t              ";
+  cout << "          u              ";
+  cout << "          v              ";
+  cout << "        u err            ";
+  cout << "        v err            " << endl;
+  for (int i = 0; i < 9; i++) { cout << "--------------"; }
+  cout << endl;
+
+  cout << setw(22) << tret << setw(25) << ydata[0] << setw(25) << ydata[1]
+       << setw(25) << abs(ydata[0] - utrue) << setw(25) << abs(ydata[1] - vtrue)
+       << endl;
+
+  // Advance in time
+  for (int i = 0; i < nout; i++)
+  {
+    flag = ARKodeEvolve(arkode_mem, tout, y, &tret, ARK_ONE_STEP);
+    if (check_flag(flag, "ARKode")) { return 1; }
+
+    flag = true_sol(tret, &utrue, &vtrue);
+    if (check_flag(flag, "true_sol")) { return 1; }
+
+    cout << setw(22) << tret << setw(25) << ydata[0] << setw(25) << ydata[1]
+         << setw(25) << abs(ydata[0] - utrue) << setw(25)
+         << abs(ydata[1] - vtrue) << endl;
+
+    // update output time
+    tout += dtout;
+  }
+  for (int i = 0; i < 9; i++) { cout << "--------------"; }
+  cout << endl;
+
+  // Print some final statistics
+  flag = ARKodePrintAllStats(arkode_mem, stdout, SUN_OUTPUTFORMAT_TABLE);
+  if (check_flag(flag, "ARKodePrintAllStats")) { return 1; }
+
+  // Clean up and return with successful completion
+  N_VDestroy(y);
+  SUNMatDestroy(A);
+  SUNLinSolFree(LS);
+  MRIStepInnerStepper_Free(&stepper);
+  ARKodeFree(&inner_arkode_mem);
+  ARKodeFree(&arkode_mem);
+
+  cout << "End MRIStep StageInfo test" << endl;
+
+  return 0;
+}
+
+// Callback functions
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step failure processing at t = "
+            << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << ")," << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-RHS processing (stage " << stage << " of " << max_stages
+            << ") at t = " << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << "), " << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-stage processing (stage " << stage << " of "
+            << max_stages << ") at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "), "
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+/*---- end of file ----*/
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_0.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_0.out
new file mode 100644
index 0000000000..d9e0a94bac
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_0.out
@@ -0,0 +1,52 @@
+Start MRIStep StageInfo test
+Using Ex-MRI-GARK method
+           t                        u                        v                      u err                    v err            
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Post-stage processing (stage 1 of 4) at t = 3.33e-04 (tn = 0.00e+00 , tcur = 3.33e-04), ||y||_2 = 2.1213151057e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 3.33e-04 (tn = 0.00e+00 , tcur = 3.33e-04), ||y||_2 = 2.1213151057e+00]
+    [Post-stage processing (stage 2 of 4) at t = 7.50e-04 (tn = 0.00e+00 , tcur = 7.50e-04), ||y||_2 = 2.1212937905e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 7.50e-04 (tn = 0.00e+00 , tcur = 7.50e-04), ||y||_2 = 2.1212937905e+00]
+    [Post-stage processing (stage 3 of 4) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-step processing at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+      1.0000000000e-03         1.2247447693e+00         1.7319930735e+00         2.2426505097e-14         1.9984014443e-15
+    [Pre-step processing at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-stage processing (stage 1 of 4) at t = 1.33e-03 (tn = 1.00e-03 , tcur = 1.33e-03), ||y||_2 = 2.1212364434e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 1.33e-03 (tn = 1.00e-03 , tcur = 1.33e-03), ||y||_2 = 2.1212364434e+00]
+    [Post-stage processing (stage 2 of 4) at t = 1.75e-03 (tn = 1.00e-03 , tcur = 1.75e-03), ||y||_2 = 2.1211758016e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 1.75e-03 (tn = 1.00e-03 , tcur = 1.75e-03), ||y||_2 = 2.1211758016e+00]
+    [Post-stage processing (stage 3 of 4) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-step processing at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+      2.0000000000e-03         1.2247444631e+00         1.7318198829e+00         4.4853010195e-14         3.7747582837e-15
+    [Pre-step processing at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-stage processing (stage 1 of 4) at t = 2.33e-03 (tn = 2.00e-03 , tcur = 2.33e-03), ||y||_2 = 2.1210634067e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 2.33e-03 (tn = 2.00e-03 , tcur = 2.33e-03), ||y||_2 = 2.1210634067e+00]
+    [Post-stage processing (stage 2 of 4) at t = 2.75e-03 (tn = 2.00e-03 , tcur = 2.75e-03), ||y||_2 = 2.1209634544e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 2.75e-03 (tn = 2.00e-03 , tcur = 2.75e-03), ||y||_2 = 2.1209634544e+00]
+    [Post-stage processing (stage 3 of 4) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956339e+00]
+    [Post-step processing at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03),||y||_2 = 2.1208956339e+00]
+      3.0000000000e-03         1.2247439528e+00         1.7315312703e+00         6.7279515292e-14         5.3290705182e-15
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.003
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 0
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.001
+Last step size                = 0.001
+Current step size             = 0.001
+Explicit slow RHS fn evals    = 9
+Implicit slow RHS fn evals    = 0
+Inner stepper failures        = 0
+NLS iters                     = 0
+NLS fails                     = 0
+NLS iters per step            = 0
+LS setups                     = 0
+End MRIStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_1.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_1.out
new file mode 100644
index 0000000000..80768d9871
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_1.out
@@ -0,0 +1,110 @@
+Start MRIStep StageInfo test
+Using Im-MRI-GARK method
+Using Newton nonlinear solver
+Using GMRES iterative linear solver
+           t                        u                        v                      u err                    v err            
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 8) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Post-stage processing (stage 1 of 8) at t = 3.33e-04 (tn = 0.00e+00 , tcur = 3.33e-04), ||y||_2 = 2.1213151057e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 3.33e-04 (tn = 0.00e+00 , tcur = 3.33e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 3.33e-04 (tn = 0.00e+00 , tcur = 3.33e-04), ||y||_2 = 2.1213183373e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 3.33e-04 (tn = 0.00e+00 , tcur = 3.33e-04), ||y||_2 = 2.1213213312e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 3.33e-04 (tn = 0.00e+00 , tcur = 3.33e-04), ||y||_2 = 2.1213150886e+00]
+    [Post-stage processing (stage 2 of 8) at t = 3.33e-04 (tn = 0.00e+00 , tcur = 3.33e-04), ||y||_2 = 2.1213150886e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 3.33e-04 (tn = 0.00e+00 , tcur = 3.33e-04), ||y||_2 = 2.1213150886e+00]
+    [Post-stage processing (stage 3 of 8) at t = 6.67e-04 (tn = 0.00e+00 , tcur = 6.67e-04), ||y||_2 = 2.1212993503e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 6.67e-04 (tn = 0.00e+00 , tcur = 6.67e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 6.67e-04 (tn = 0.00e+00 , tcur = 6.67e-04), ||y||_2 = 2.1213183389e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 6.67e-04 (tn = 0.00e+00 , tcur = 6.67e-04), ||y||_2 = 2.1213213345e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 6.67e-04 (tn = 0.00e+00 , tcur = 6.67e-04), ||y||_2 = 2.1212993415e+00]
+    [Post-stage processing (stage 4 of 8) at t = 6.67e-04 (tn = 0.00e+00 , tcur = 6.67e-04), ||y||_2 = 2.1212993415e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 6.67e-04 (tn = 0.00e+00 , tcur = 6.67e-04), ||y||_2 = 2.1212993415e+00]
+    [Post-stage processing (stage 5 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731966e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213183413e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213213393e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-stage processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-step processing at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+      1.0000000000e-03         1.2247447693e+00         1.7319930735e+00         2.6090241079e-13         1.1546319456e-14
+    [Pre-step processing at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 0 of 8) at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-stage processing (stage 1 of 8) at t = 1.33e-03 (tn = 1.00e-03 , tcur = 1.33e-03), ||y||_2 = 2.1212364434e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 1.33e-03 (tn = 1.00e-03 , tcur = 1.33e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 1.33e-03 (tn = 1.00e-03 , tcur = 1.33e-03), ||y||_2 = 2.1212711424e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 1.33e-03 (tn = 1.00e-03 , tcur = 1.33e-03), ||y||_2 = 2.1212741398e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 1.33e-03 (tn = 1.00e-03 , tcur = 1.33e-03), ||y||_2 = 2.1212364263e+00]
+    [Post-stage processing (stage 2 of 8) at t = 1.33e-03 (tn = 1.00e-03 , tcur = 1.33e-03), ||y||_2 = 2.1212364263e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 1.33e-03 (tn = 1.00e-03 , tcur = 1.33e-03), ||y||_2 = 2.1212364263e+00]
+    [Post-stage processing (stage 3 of 8) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.1211892263e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.1212711424e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.1212741398e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.1211892175e+00]
+    [Post-stage processing (stage 4 of 8) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.1211892175e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.1211892175e+00]
+    [Post-stage processing (stage 5 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211316142e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212711430e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212741409e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-stage processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-step processing at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+      2.0000000000e-03         1.2247444631e+00         1.7318198829e+00         2.9067859231e-12         2.3980817332e-14
+    [Pre-step processing at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 0 of 8) at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-stage processing (stage 1 of 8) at t = 2.33e-03 (tn = 2.00e-03 , tcur = 2.33e-03), ||y||_2 = 2.1210634067e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 2.33e-03 (tn = 2.00e-03 , tcur = 2.33e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 2.33e-03 (tn = 2.00e-03 , tcur = 2.33e-03), ||y||_2 = 2.1211295605e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 2.33e-03 (tn = 2.00e-03 , tcur = 2.33e-03), ||y||_2 = 2.1211325579e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 2.33e-03 (tn = 2.00e-03 , tcur = 2.33e-03), ||y||_2 = 2.1210633896e+00]
+    [Post-stage processing (stage 2 of 8) at t = 2.33e-03 (tn = 2.00e-03 , tcur = 2.33e-03), ||y||_2 = 2.1210633896e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 2.33e-03 (tn = 2.00e-03 , tcur = 2.33e-03), ||y||_2 = 2.1210633896e+00]
+    [Post-stage processing (stage 3 of 8) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.1209847405e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.1211295605e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.1211325579e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.1209847317e+00]
+    [Post-stage processing (stage 4 of 8) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.1209847317e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.1209847317e+00]
+    [Post-stage processing (stage 5 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956853e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211295608e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211325586e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956339e+00]
+    [Post-stage processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956339e+00]
+    [Post-step processing at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03),||y||_2 = 2.1208956339e+00]
+      3.0000000000e-03         1.2247439528e+00         1.7315312703e+00         1.0538681039e-11         3.7747582837e-14
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.003
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 0
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.001
+Last step size                = 0.001
+Current step size             = 0.001
+Explicit slow RHS fn evals    = 0
+Implicit slow RHS fn evals    = 27
+Inner stepper failures        = 0
+NLS iters                     = 18
+NLS fails                     = 0
+NLS iters per step            = 6
+LS setups                     = 0
+Jac fn evals                  = 0
+LS RHS fn evals               = 18
+Prec setup evals              = 0
+Prec solves                   = 0
+LS iters                      = 18
+LS fails                      = 0
+Jac-times setups              = 0
+Jac-times evals               = 18
+LS iters per NLS iter         = 1
+Jac evals per NLS iter        = 0
+Prec evals per NLS iter       = 0
+End MRIStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_2.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_2.out
new file mode 100644
index 0000000000..fcad2aa93a
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_2.out
@@ -0,0 +1,116 @@
+Start MRIStep StageInfo test
+Using ImEx-MRI-GARK method
+Using Newton nonlinear solver
+Using GMRES iterative linear solver
+           t                        u                        v                      u err                    v err            
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 8) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Post-stage processing (stage 1 of 8) at t = 4.36e-04 (tn = 0.00e+00 , tcur = 4.36e-04), ||y||_2 = 2.1213113879e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 4.36e-04 (tn = 0.00e+00 , tcur = 4.36e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 4.36e-04 (tn = 0.00e+00 , tcur = 4.36e-04), ||y||_2 = 2.1213183438e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 4.36e-04 (tn = 0.00e+00 , tcur = 4.36e-04), ||y||_2 = 2.1213213443e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 4.36e-04 (tn = 0.00e+00 , tcur = 4.36e-04), ||y||_2 = 2.1213113879e+00]
+    [Post-stage processing (stage 2 of 8) at t = 4.36e-04 (tn = 0.00e+00 , tcur = 4.36e-04), ||y||_2 = 2.1213113879e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 4.36e-04 (tn = 0.00e+00 , tcur = 4.36e-04), ||y||_2 = 2.1213113879e+00]
+    [Post-stage processing (stage 3 of 8) at t = 7.18e-04 (tn = 0.00e+00 , tcur = 7.18e-04), ||y||_2 = 2.1212960228e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 7.18e-04 (tn = 0.00e+00 , tcur = 7.18e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 7.18e-04 (tn = 0.00e+00 , tcur = 7.18e-04), ||y||_2 = 2.1213183421e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 7.18e-04 (tn = 0.00e+00 , tcur = 7.18e-04), ||y||_2 = 2.1213213409e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 7.18e-04 (tn = 0.00e+00 , tcur = 7.18e-04), ||y||_2 = 2.1212960259e+00]
+    [Post-stage processing (stage 4 of 8) at t = 7.18e-04 (tn = 0.00e+00 , tcur = 7.18e-04), ||y||_2 = 2.1212960259e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 7.18e-04 (tn = 0.00e+00 , tcur = 7.18e-04), ||y||_2 = 2.1212960259e+00]
+    [Post-stage processing (stage 5 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731087e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213183406e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213213379e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731290e+00]
+    [Post-stage processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731290e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731290e+00]
+    [Post-stage processing (stage 7 of 8) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-step processing at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+      1.0000000000e-03         1.2247447693e+00         1.7319930735e+00         2.6378899065e-13         8.2156503822e-15
+    [Pre-step processing at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 0 of 8) at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-stage processing (stage 1 of 8) at t = 1.44e-03 (tn = 1.00e-03 , tcur = 1.44e-03), ||y||_2 = 2.1212230476e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 1.44e-03 (tn = 1.00e-03 , tcur = 1.44e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 1.44e-03 (tn = 1.00e-03 , tcur = 1.44e-03), ||y||_2 = 2.1212711435e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 1.44e-03 (tn = 1.00e-03 , tcur = 1.44e-03), ||y||_2 = 2.1212741418e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 1.44e-03 (tn = 1.00e-03 , tcur = 1.44e-03), ||y||_2 = 2.1212230476e+00]
+    [Post-stage processing (stage 2 of 8) at t = 1.44e-03 (tn = 1.00e-03 , tcur = 1.44e-03), ||y||_2 = 2.1212230476e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 1.44e-03 (tn = 1.00e-03 , tcur = 1.44e-03), ||y||_2 = 2.1212230476e+00]
+    [Post-stage processing (stage 3 of 8) at t = 1.72e-03 (tn = 1.00e-03 , tcur = 1.72e-03), ||y||_2 = 2.1211810603e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 1.72e-03 (tn = 1.00e-03 , tcur = 1.72e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 1.72e-03 (tn = 1.00e-03 , tcur = 1.72e-03), ||y||_2 = 2.1212711432e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 1.72e-03 (tn = 1.00e-03 , tcur = 1.72e-03), ||y||_2 = 2.1212741414e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 1.72e-03 (tn = 1.00e-03 , tcur = 1.72e-03), ||y||_2 = 2.1211810634e+00]
+    [Post-stage processing (stage 4 of 8) at t = 1.72e-03 (tn = 1.00e-03 , tcur = 1.72e-03), ||y||_2 = 2.1211810634e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 1.72e-03 (tn = 1.00e-03 , tcur = 1.72e-03), ||y||_2 = 2.1211810634e+00]
+    [Post-stage processing (stage 5 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315263e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212711428e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212741405e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315465e+00]
+    [Post-stage processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315465e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315465e+00]
+    [Post-stage processing (stage 7 of 8) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-step processing at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+      2.0000000000e-03         1.2247444631e+00         1.7318198829e+00         3.1354918661e-12         1.3988810110e-14
+    [Pre-step processing at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 0 of 8) at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-stage processing (stage 1 of 8) at t = 2.44e-03 (tn = 2.00e-03 , tcur = 2.44e-03), ||y||_2 = 2.1210403366e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 2.44e-03 (tn = 2.00e-03 , tcur = 2.44e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 2.44e-03 (tn = 2.00e-03 , tcur = 2.44e-03), ||y||_2 = 2.1211295611e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 2.44e-03 (tn = 2.00e-03 , tcur = 2.44e-03), ||y||_2 = 2.1211325591e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 2.44e-03 (tn = 2.00e-03 , tcur = 2.44e-03), ||y||_2 = 2.1210403366e+00]
+    [Post-stage processing (stage 2 of 8) at t = 2.44e-03 (tn = 2.00e-03 , tcur = 2.44e-03), ||y||_2 = 2.1210403366e+00]
+    [Pre-RHS processing (stage 2 of 8) at t = 2.44e-03 (tn = 2.00e-03 , tcur = 2.44e-03), ||y||_2 = 2.1210403366e+00]
+    [Post-stage processing (stage 3 of 8) at t = 2.72e-03 (tn = 2.00e-03 , tcur = 2.72e-03), ||y||_2 = 2.1209717381e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 2.72e-03 (tn = 2.00e-03 , tcur = 2.72e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 2.72e-03 (tn = 2.00e-03 , tcur = 2.72e-03), ||y||_2 = 2.1211295610e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 2.72e-03 (tn = 2.00e-03 , tcur = 2.72e-03), ||y||_2 = 2.1211325588e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 2.72e-03 (tn = 2.00e-03 , tcur = 2.72e-03), ||y||_2 = 2.1209717412e+00]
+    [Post-stage processing (stage 4 of 8) at t = 2.72e-03 (tn = 2.00e-03 , tcur = 2.72e-03), ||y||_2 = 2.1209717412e+00]
+    [Pre-RHS processing (stage 4 of 8) at t = 2.72e-03 (tn = 2.00e-03 , tcur = 2.72e-03), ||y||_2 = 2.1209717412e+00]
+    [Post-stage processing (stage 5 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208955974e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211295607e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211325583e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956177e+00]
+    [Post-stage processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956177e+00]
+    [Pre-RHS processing (stage 6 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956177e+00]
+    [Post-stage processing (stage 7 of 8) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956339e+00]
+    [Post-step processing at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03),||y||_2 = 2.1208956339e+00]
+      3.0000000000e-03         1.2247439528e+00         1.7315312703e+00         1.1467271577e-11         1.8207657604e-14
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.003
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 0
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.001
+Last step size                = 0.001
+Current step size             = 0.001
+Explicit slow RHS fn evals    = 12
+Implicit slow RHS fn evals    = 30
+Inner stepper failures        = 0
+NLS iters                     = 18
+NLS fails                     = 0
+NLS iters per step            = 6
+LS setups                     = 0
+Jac fn evals                  = 0
+LS RHS fn evals               = 18
+Prec setup evals              = 0
+Prec solves                   = 0
+LS iters                      = 18
+LS fails                      = 0
+Jac-times setups              = 0
+Jac-times evals               = 18
+LS iters per NLS iter         = 1
+Jac evals per NLS iter        = 0
+Prec evals per NLS iter       = 0
+End MRIStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_3.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_3.out
new file mode 100644
index 0000000000..4ddd50175a
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_3.out
@@ -0,0 +1,58 @@
+Start MRIStep StageInfo test
+Using Ex-MRI-SR method
+           t                        u                        v                      u err                    v err            
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Post-stage processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1212987717e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1212987717e+00]
+    [Post-stage processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1212901822e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1212901822e+00]
+    [Post-stage processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1212596852e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1212596852e+00]
+    [Post-stage processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-step processing at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+      1.0000000000e-03         1.2247447693e+00         1.7319930735e+00         7.9936057773e-15         1.3744561045e-13
+    [Pre-step processing at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-stage processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1211877224e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1211877224e+00]
+    [Post-stage processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1211674743e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1211674743e+00]
+    [Post-stage processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1211055205e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1211055205e+00]
+    [Post-stage processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-step processing at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+      2.0000000000e-03         1.2247444631e+00         1.7318198829e+00         1.5987211555e-14         2.6245672302e-13
+    [Pre-step processing at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-stage processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1209823117e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1209823117e+00]
+    [Post-stage processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1209504105e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1209504105e+00]
+    [Post-stage processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1208570163e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1208570163e+00]
+    [Post-stage processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956339e+00]
+    [Post-step processing at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03),||y||_2 = 2.1208956339e+00]
+      3.0000000000e-03         1.2247439528e+00         1.7315312703e+00         2.4202861937e-14         3.7436720390e-13
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.003
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 0
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.001
+Last step size                = 0.001
+Current step size             = 0.001
+Explicit slow RHS fn evals    = 12
+Implicit slow RHS fn evals    = 0
+Inner stepper failures        = 0
+NLS iters                     = 0
+NLS fails                     = 0
+NLS iters per step            = 0
+LS setups                     = 0
+End MRIStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_4.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_4.out
new file mode 100644
index 0000000000..e28d9326b8
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_4.out
@@ -0,0 +1,119 @@
+Start MRIStep StageInfo test
+Using Im-MRI-SR method
+Using Newton nonlinear solver
+Using GMRES iterative linear solver
+           t                        u                        v                      u err                    v err            
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1213183396e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1213213360e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1212987262e+00]
+    [Post-stage processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1212987262e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1212987262e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1213183393e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1213213353e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1212901049e+00]
+    [Post-stage processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1212901049e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1212901049e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1213183421e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1213213410e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1212597444e+00]
+    [Post-stage processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1212597444e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1212597444e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213183414e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213213394e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-stage processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-step processing at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+      1.0000000000e-03         1.2247447693e+00         1.7319930735e+00         2.4846791291e-13         1.5143442056e-13
+    [Pre-step processing at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1212711427e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1212741403e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1211876769e+00]
+    [Post-stage processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1211876769e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1211876769e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1212711425e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1212741399e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1211673971e+00]
+    [Post-stage processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1211673971e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1211673971e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1212711434e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1212741417e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1211055797e+00]
+    [Post-stage processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1211055797e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1211055797e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212711431e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212741411e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-stage processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-step processing at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+      2.0000000000e-03         1.2247444631e+00         1.7318198829e+00         2.6707525080e-12         2.9021229864e-13
+    [Pre-step processing at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1211295607e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1211325583e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1209822662e+00]
+    [Post-stage processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1209822662e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1209822662e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1211295606e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1211325581e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1209503332e+00]
+    [Post-stage processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1209503332e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1209503332e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1211295611e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1211325591e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1208570755e+00]
+    [Post-stage processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1208570755e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1208570755e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211295609e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211325588e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956339e+00]
+    [Post-stage processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956339e+00]
+    [Post-step processing at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03),||y||_2 = 2.1208956339e+00]
+      3.0000000000e-03         1.2247439528e+00         1.7315312703e+00         9.4586560806e-12         4.1744385726e-13
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.003
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 0
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.001
+Last step size                = 0.001
+Current step size             = 0.001
+Explicit slow RHS fn evals    = 0
+Implicit slow RHS fn evals    = 36
+Inner stepper failures        = 0
+NLS iters                     = 24
+NLS fails                     = 0
+NLS iters per step            = 8
+LS setups                     = 0
+Jac fn evals                  = 0
+LS RHS fn evals               = 24
+Prec setup evals              = 0
+Prec solves                   = 0
+LS iters                      = 24
+LS fails                      = 0
+Jac-times setups              = 0
+Jac-times evals               = 24
+LS iters per NLS iter         = 1
+Jac evals per NLS iter        = 0
+Prec evals per NLS iter       = 0
+End MRIStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_5.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_5.out
new file mode 100644
index 0000000000..7780877a70
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_5.out
@@ -0,0 +1,119 @@
+Start MRIStep StageInfo test
+Using ImEx-MRI-SR method
+Using Newton nonlinear solver
+Using GMRES iterative linear solver
+           t                        u                        v                      u err                    v err            
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1213183438e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1213213444e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1212987717e+00]
+    [Post-stage processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1212987717e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 6.76e-04 (tn = 0.00e+00 , tcur = 6.76e-04), ||y||_2 = 2.1212987717e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1213183444e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1213213455e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1212901821e+00]
+    [Post-stage processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1212901821e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 8.00e-04 (tn = 0.00e+00 , tcur = 8.00e-04), ||y||_2 = 2.1212901821e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1213183402e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1213213371e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1212596854e+00]
+    [Post-stage processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1212596854e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 1.13e-03 (tn = 0.00e+00 , tcur = 1.13e-03), ||y||_2 = 2.1212596854e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213183414e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1213213394e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-stage processing (stage 4 of 5) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-step processing at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+      1.0000000000e-03         1.2247447693e+00         1.7319930735e+00         2.8288482667e-13         1.3744561045e-13
+    [Pre-step processing at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1212711437e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1212741424e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1211877224e+00]
+    [Post-stage processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1211877224e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 1.68e-03 (tn = 1.00e-03 , tcur = 1.68e-03), ||y||_2 = 2.1211877224e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1212711440e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1212741429e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1211674743e+00]
+    [Post-stage processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1211674743e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 1.80e-03 (tn = 1.00e-03 , tcur = 1.80e-03), ||y||_2 = 2.1211674743e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1212711427e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1212741403e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1211055207e+00]
+    [Post-stage processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1211055207e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 2.13e-03 (tn = 1.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.1211055207e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212711431e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1212741411e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-stage processing (stage 4 of 5) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-step processing at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+      2.0000000000e-03         1.2247444631e+00         1.7318198829e+00         2.7395863356e-12         2.6245672302e-13
+    [Pre-step processing at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 0 of 5) at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1211295613e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1211325595e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1209823117e+00]
+    [Post-stage processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1209823117e+00]
+    [Pre-RHS processing (stage 1 of 5) at t = 2.68e-03 (tn = 2.00e-03 , tcur = 2.68e-03), ||y||_2 = 2.1209823117e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1211295614e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1211325598e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1209504105e+00]
+    [Post-stage processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1209504105e+00]
+    [Pre-RHS processing (stage 2 of 5) at t = 2.80e-03 (tn = 2.00e-03 , tcur = 2.80e-03), ||y||_2 = 2.1209504105e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1211295607e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1211325583e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1208570165e+00]
+    [Post-stage processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1208570165e+00]
+    [Pre-RHS processing (stage 3 of 5) at t = 3.13e-03 (tn = 2.00e-03 , tcur = 3.13e-03), ||y||_2 = 2.1208570165e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211295609e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1211325588e+00]
+    [Pre-RHS processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956339e+00]
+    [Post-stage processing (stage 4 of 5) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956339e+00]
+    [Post-step processing at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03),||y||_2 = 2.1208956339e+00]
+      3.0000000000e-03         1.2247439528e+00         1.7315312703e+00         9.5614627327e-12         3.7592151614e-13
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.003
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 0
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.001
+Last step size                = 0.001
+Current step size             = 0.001
+Explicit slow RHS fn evals    = 12
+Implicit slow RHS fn evals    = 36
+Inner stepper failures        = 0
+NLS iters                     = 24
+NLS fails                     = 0
+NLS iters per step            = 8
+LS setups                     = 0
+Jac fn evals                  = 0
+LS RHS fn evals               = 24
+Prec setup evals              = 0
+Prec solves                   = 0
+LS iters                      = 24
+LS fails                      = 0
+Jac-times setups              = 0
+Jac-times evals               = 24
+LS iters per NLS iter         = 1
+Jac evals per NLS iter        = 0
+Prec evals per NLS iter       = 0
+End MRIStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_6.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_6.out
new file mode 100644
index 0000000000..92ab1f21fe
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_mristep_6.out
@@ -0,0 +1,52 @@
+Start MRIStep StageInfo test
+Using MERK method
+           t                        u                        v                      u err                    v err            
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    1.224744871391589e+00    1.732050807568877e+00    0.000000000000000e+00    0.000000000000000e+00
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.1213203436e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.1213203436e+00]
+    [Post-stage processing (stage 1 of 4) at t = 5.00e-04 (tn = 0.00e+00 , tcur = 5.00e-04), ||y||_2 = 2.1213085585e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 5.00e-04 (tn = 0.00e+00 , tcur = 5.00e-04), ||y||_2 = 2.1213085585e+00]
+    [Post-stage processing (stage 2 of 4) at t = 6.67e-04 (tn = 0.00e+00 , tcur = 6.67e-04), ||y||_2 = 2.1212993663e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 6.67e-04 (tn = 0.00e+00 , tcur = 6.67e-04), ||y||_2 = 2.1212993663e+00]
+    [Post-stage processing (stage 3 of 4) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-step processing at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+      1.0000000000e-03         1.2247447693e+00         1.7319930735e+00         3.3528735344e-14         1.4566126083e-13
+    [Pre-step processing at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03),||y||_2 = 2.1212731452e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03), ||y||_2 = 2.1212731452e+00]
+    [Post-stage processing (stage 1 of 4) at t = 1.50e-03 (tn = 1.00e-03 , tcur = 1.50e-03), ||y||_2 = 2.1212141650e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 1.50e-03 (tn = 1.00e-03 , tcur = 1.50e-03), ||y||_2 = 2.1212141650e+00]
+    [Post-stage processing (stage 2 of 4) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.1211892422e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.1211892422e+00]
+    [Post-stage processing (stage 3 of 4) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-step processing at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+      2.0000000000e-03         1.2247444631e+00         1.7318198829e+00         6.7057470687e-14         2.7866597918e-13
+    [Pre-step processing at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03),||y||_2 = 2.1211315628e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.1211315628e+00]
+    [Post-stage processing (stage 1 of 4) at t = 2.50e-03 (tn = 2.00e-03 , tcur = 2.50e-03), ||y||_2 = 2.1210254031e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 2.50e-03 (tn = 2.00e-03 , tcur = 2.50e-03), ||y||_2 = 2.1210254031e+00]
+    [Post-stage processing (stage 2 of 4) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.1209847564e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.1209847564e+00]
+    [Post-stage processing (stage 3 of 4) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.1208956339e+00]
+    [Post-step processing at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03),||y||_2 = 2.1208956339e+00]
+      3.0000000000e-03         1.2247439528e+00         1.7315312703e+00         1.0058620603e-13         3.9879211045e-13
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.003
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 0
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.001
+Last step size                = 0.001
+Current step size             = 0.001
+Explicit slow RHS fn evals    = 9
+Implicit slow RHS fn evals    = 0
+Inner stepper failures        = 0
+NLS iters                     = 0
+NLS fails                     = 0
+NLS iters per step            = 0
+LS setups                     = 0
+End MRIStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_splittingstep.cpp b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_splittingstep.cpp
new file mode 100644
index 0000000000..66b1ee3357
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_splittingstep.cpp
@@ -0,0 +1,296 @@
+/* -----------------------------------------------------------------------------
+ * Programmer(s): Daniel R. Reynolds @ UMBC
+ * -----------------------------------------------------------------------------
+ * SUNDIALS Copyright Start
+ * Copyright (c) 2025-2026, Lawrence Livermore National Security,
+ * University of Maryland Baltimore County, and the SUNDIALS contributors.
+ * Copyright (c) 2013-2025, Lawrence Livermore National Security
+ * and Southern Methodist University.
+ * Copyright (c) 2002-2013, Lawrence Livermore National Security.
+ * All rights reserved.
+ *
+ * See the top-level LICENSE and NOTICE files for details.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ * SUNDIALS Copyright End
+ * -----------------------------------------------------------------------------
+ * Test stage information and pre/postprocessing routines in SplittingStep
+ * ---------------------------------------------------------------------------*/
+
+#include <cmath>
+#include <cstdio>
+#include <iomanip>
+#include <iostream>
+#include <limits>
+
+// Include desired integrators and vectors
+#include "arkode/arkode_erkstep.h"
+#include "arkode/arkode_splittingstep.h"
+#include "nvector/nvector_serial.h"
+#include "sundials/sundials_context.hpp"
+
+#include "problems/estep.hpp"
+#include "utilities/check_return.hpp"
+
+using namespace std;
+using namespace problems::estep;
+
+// Store the main integrator global memory for these tests only, so that we
+// can call ARKodeGetLastTime etc in the step and stage pre/postprocessing
+// callback functions below.  This would normally be stored in user_data, but
+// here we reuse problem definitions from other tests.
+void* arkode_mem = nullptr;
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data);
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+
+int main(int argc, char* argv[])
+{
+  cout << "Start SplittingStep StageInfo test" << endl;
+
+  // SUNDIALS context object for this simulation
+  sundials::Context sunctx;
+
+  // Step sizes: overall, partition 1, partition 2
+  sunrealtype dt   = SUN_RCONST(0.001);
+  sunrealtype dt_1 = dt / 2;
+  sunrealtype dt_2 = dt / 4;
+
+  // Create initial condition
+  N_Vector y = N_VNew_Serial(1, sunctx);
+  if (check_ptr(y, "N_VNew_Serial")) { return 1; }
+
+  int flag = initial_condition(y);
+  if (check_flag(flag, "initial_condition")) { return 1; }
+
+  // Create partition 1 integrator
+  void* stepper_1 = ERKStepCreate(ode_rhs_1, zero, y, sunctx);
+  if (check_ptr(stepper_1, "ERKStepCreate")) { return 1; }
+
+  flag = ARKodeSetUserData(stepper_1, &problem_data);
+  if (check_flag(flag, "ARKodeSetUserData")) { return 1; }
+
+  flag = ARKodeSetFixedStep(stepper_1, dt_1);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  // Create partition 1 integrator
+  void* stepper_2 = ERKStepCreate(ode_rhs_2, zero, y, sunctx);
+  if (check_ptr(stepper_2, "ERKStepCreate")) { return 1; }
+
+  flag = ARKodeSetFixedStep(stepper_2, dt_2);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  // Create the overall integrator
+  SUNStepper steppers[2];
+
+  flag = ARKodeCreateSUNStepper(stepper_1, &steppers[0]);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  flag = ARKodeCreateSUNStepper(stepper_2, &steppers[1]);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  arkode_mem = SplittingStepCreate(steppers, 2, zero, y, sunctx);
+  if (check_ptr(arkode_mem, "SplittingStepCreate")) { return 1; }
+
+  flag = ARKodeSetFixedStep(arkode_mem, dt);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  // Set pre/post step and stage routines
+  flag = ARKodeSetPreprocessStepFn(arkode_mem, preprocess_step);
+  if (check_flag(flag, "ARKodeSetPreprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFn(arkode_mem, postprocess_step);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFailFn(arkode_mem, postprocess_step_fail);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFailFn")) { return 1; }
+  flag = ARKodeSetPreprocessRHSFn(arkode_mem, preprocess_stage);
+  if (check_flag(flag, "ARKodeSetPreprocessRHSFn")) { return 1; }
+  flag = ARKodeSetPostprocessStageFn(arkode_mem, postprocess_stage);
+  if (check_flag(flag, "ARKodeSetPostprocessStageFn")) { return 1; }
+
+  // True solution vector
+  N_Vector yt = N_VClone(y);
+
+  flag = true_solution(zero, problem_data, yt);
+  if (check_flag(flag, "true_solution")) { return 1; }
+
+  // Initial time and fist output time
+  const sunrealtype dtout = one; // output interval
+  const int nout          = 3;   // number of outputs
+  sunrealtype tret        = zero;
+  sunrealtype tout        = tret + dtout;
+
+  const int width = numeric_limits<sunrealtype>::digits10 + 8;
+
+  // Output initial contion
+  cout << scientific;
+  cout << setprecision(numeric_limits<sunrealtype>::digits10);
+  cout << setw(width) << " t";
+  cout << setw(width) << " y";
+  cout << setw(width) << " y err" << endl;
+  for (int i = 0; i < 3 * width; i++) { cout << "-"; }
+  cout << endl;
+
+  sunrealtype* y_data  = N_VGetArrayPointer(y);
+  sunrealtype* yt_data = N_VGetArrayPointer(yt);
+
+  cout << setw(width) << tret << setw(width) << y_data[0] << setw(width)
+       << abs(y_data[0] - yt_data[0]) << endl;
+
+  // Advance in time
+  for (int i = 0; i < nout; i++)
+  {
+    flag = ARKodeEvolve(arkode_mem, tout, y, &tret, ARK_ONE_STEP);
+    if (check_flag(flag, "ARKodeEvolve")) { return 1; }
+
+    flag = true_solution(tret, problem_data, yt);
+    if (check_flag(flag, "true_solution")) { return 1; }
+
+    cout << setw(width) << tret << setw(width) << y_data[0] << setw(width)
+         << abs(y_data[0] - yt_data[0]) << endl;
+
+    // update output time
+    tout += dtout;
+  }
+  for (int i = 0; i < 3 * width; i++) { cout << "-"; }
+  cout << endl;
+
+  // Print some final statistics
+  flag = ARKodePrintAllStats(arkode_mem, stdout, SUN_OUTPUTFORMAT_TABLE);
+  if (check_flag(flag, "ARKodePrintAllStats")) { return 1; }
+
+  // Clean up and return with successful completion
+  N_VDestroy(y);
+  N_VDestroy(yt);
+  ARKodeFree(&arkode_mem);
+  ARKodeFree(&stepper_1);
+  ARKodeFree(&stepper_2);
+  SUNStepper_Destroy(&steppers[0]);
+  SUNStepper_Destroy(&steppers[1]);
+
+  cout << "End SplittingStep StageInfo test" << endl;
+
+  return 0;
+}
+
+// Callback functions
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step failure processing at t = "
+            << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << ")," << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-RHS processing (stage " << stage << " of " << max_stages
+            << ") at t = " << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << "), " << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-stage processing (stage " << stage << " of "
+            << max_stages << ") at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "), "
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+/*---- end of file ----*/
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_splittingstep.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_splittingstep.out
new file mode 100644
index 0000000000..3e8770502d
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_splittingstep.out
@@ -0,0 +1,28 @@
+Start SplittingStep StageInfo test
+                      t                      y                  y err
+---------------------------------------------------------------------
+  0.000000000000000e+00  1.000000000000000e+00  0.000000000000000e+00
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 1.0000000000e+00]
+    [Post-step processing at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03),||y||_2 = 9.9899900167e-01]
+       1.0000000000e-03       9.9899900167e-01       9.9866566894e-07
+    [Pre-step processing at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03),||y||_2 = 9.9899900167e-01]
+    [Post-step processing at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03),||y||_2 = 9.9799800734e-01]
+       2.0000000000e-03       9.9799800734e-01       1.9953280224e-06
+    [Pre-step processing at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03),||y||_2 = 9.9799800734e-01]
+    [Post-step processing at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03),||y||_2 = 9.9699701901e-01]
+       3.0000000000e-03       9.9699701901e-01       2.9899850904e-06
+---------------------------------------------------------------------
+Current time                  = 0.003
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 0
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.001
+Last step size                = 0.001
+Current step size             = 0.001
+Partition 1 evolves           = 3
+Partition 2 evolves           = 3
+End SplittingStep StageInfo test
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_sprkstep.cpp b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_sprkstep.cpp
new file mode 100644
index 0000000000..8e953e73c2
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_sprkstep.cpp
@@ -0,0 +1,253 @@
+/* -----------------------------------------------------------------------------
+ * Programmer(s): Daniel R. Reynolds @ UMBC
+ * -----------------------------------------------------------------------------
+ * SUNDIALS Copyright Start
+ * Copyright (c) 2025-2026, Lawrence Livermore National Security,
+ * University of Maryland Baltimore County, and the SUNDIALS contributors.
+ * Copyright (c) 2013-2025, Lawrence Livermore National Security
+ * and Southern Methodist University.
+ * Copyright (c) 2002-2013, Lawrence Livermore National Security.
+ * All rights reserved.
+ *
+ * See the top-level LICENSE and NOTICE files for details.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ * SUNDIALS Copyright End
+ * -----------------------------------------------------------------------------
+ * Test stage information and pre/postprocessing routines in SPRKStep
+ * ---------------------------------------------------------------------------*/
+
+#include <cmath>
+#include <cstdio>
+#include <iomanip>
+#include <iostream>
+#include <limits>
+
+// Include desired integrators, vectors, linear solvers, and nonlinear solvers
+#include "arkode/arkode_sprkstep.h"
+#include "nvector/nvector_serial.h"
+#include "sundials/sundials_context.hpp"
+
+#include "problems/kepler.hpp"
+#include "utilities/check_return.hpp"
+
+using namespace std;
+using namespace problems::kepler;
+
+// Store the main integrator global memory for these tests only, so that we
+// can call ARKodeGetLastTime etc in the step and stage pre/postprocessing
+// callback functions below.  This would normally be stored in user_data, but
+// here we reuse problem definitions from other tests.
+void* arkode_mem = nullptr;
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data);
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data);
+
+int main(int argc, char* argv[])
+{
+  cout << "Start SPRKStep StageInfo test" << endl;
+
+  // SUNDIALS context object for this simulation
+  sundials::Context sunctx;
+
+  // Create initial condition
+  N_Vector y = N_VNew_Serial(4, sunctx);
+  if (check_ptr(y, "N_VNew_Serial")) { return 1; }
+
+  int flag = initial_condition(y, eccentricity);
+  if (check_flag(flag, "initial_condition")) { return 1; }
+
+  // Create SPRKStep memory structure
+  arkode_mem = SPRKStepCreate(ode_rhs_force, ode_rhs_velocity, zero, y, sunctx);
+  if (check_ptr(arkode_mem, "SPKStepCreate")) { return 1; }
+
+  // Step size
+  const sunrealtype dt = SUN_RCONST(0.001);
+  flag                 = ARKodeSetFixedStep(arkode_mem, dt);
+  if (check_flag(flag, "ARKodeSetFixedStep")) { return 1; }
+
+  // Set pre/post step and stage routines
+  flag = ARKodeSetPreprocessStepFn(arkode_mem, preprocess_step);
+  if (check_flag(flag, "ARKodeSetPreprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFn(arkode_mem, postprocess_step);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFn")) { return 1; }
+  flag = ARKodeSetPostprocessStepFailFn(arkode_mem, postprocess_step_fail);
+  if (check_flag(flag, "ARKodeSetPostprocessStepFailFn")) { return 1; }
+  flag = ARKodeSetPreprocessRHSFn(arkode_mem, preprocess_stage);
+  if (check_flag(flag, "ARKodeSetPreprocessRHSFn")) { return 1; }
+  flag = ARKodeSetPostprocessStageFn(arkode_mem, postprocess_stage);
+  if (check_flag(flag, "ARKodeSetPostprocessStageFn")) { return 1; }
+
+  // Initial time and fist output time
+  const sunrealtype dtout = dt; // output interval
+  const int nout          = 3;  // number of outputs
+  sunrealtype tret        = zero;
+  sunrealtype tout        = tret + dtout;
+
+  // Output initial contion
+  sunrealtype* ydata = N_VGetArrayPointer(y);
+  if (check_ptr(y, "N_VGetArrayPointer")) { return 1; }
+
+  cout << scientific;
+  cout << setprecision(numeric_limits<sunrealtype>::digits10);
+  cout << "           t              ";
+  cout << "          q1             ";
+  cout << "          q2             ";
+  cout << "        q3               ";
+  cout << "        q4               " << endl;
+  for (int i = 0; i < 9; i++) { cout << "--------------"; }
+  cout << endl;
+
+  cout << setw(22) << tret << setw(25) << ydata[0] << setw(25) << ydata[1]
+       << setw(25) << ydata[2] << setw(25) << ydata[3] << endl;
+
+  // Advance in time
+  for (int i = 0; i < nout; i++)
+  {
+    flag = ARKodeEvolve(arkode_mem, tout, y, &tret, ARK_ONE_STEP);
+    if (check_flag(flag, "ARKodeEvolve")) { return 1; }
+
+    cout << setw(22) << tret << setw(25) << ydata[0] << setw(25) << ydata[1]
+         << setw(25) << ydata[2] << setw(25) << ydata[3] << endl;
+
+    // update output time
+    tout += dtout;
+  }
+  for (int i = 0; i < 9; i++) { cout << "--------------"; }
+  cout << endl;
+
+  // Print some final statistics
+  flag = ARKodePrintAllStats(arkode_mem, stdout, SUN_OUTPUTFORMAT_TABLE);
+  if (check_flag(flag, "ARKodePrintAllStats")) { return 1; }
+
+  // Clean up and return with successful completion
+  N_VDestroy(y);
+  ARKodeFree(&arkode_mem);
+
+  cout << "End SPRKStep StageInfo test" << endl;
+
+  return 0;
+}
+
+// Callback functions
+static int preprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step processing at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "),"
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_step_fail(sunrealtype t, N_Vector y, void* user_data)
+{
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-step failure processing at t = "
+            << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << ")," << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int preprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Pre-RHS processing (stage " << stage << " of " << max_stages
+            << ") at t = " << std::setprecision(2) << t << " (tn = " << tn
+            << " , tcur = " << tcur << "), " << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+static int postprocess_stage(sunrealtype t, N_Vector y, void* user_data)
+{
+  int stage, max_stages;
+  sunrealtype tn, tcur;
+  if (ARKodeGetLastTime(arkode_mem, &tn) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetLastTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetCurrentTime(arkode_mem, &tcur) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetCurrentTime" << std::endl;
+    return -1;
+  }
+  if (ARKodeGetStageIndex(arkode_mem, &stage, &max_stages) != ARK_SUCCESS)
+  {
+    std::cerr << "Error in ARKodeGetStageIndex" << std::endl;
+    return -1;
+  }
+  std::cout << "    [Post-stage processing (stage " << stage << " of "
+            << max_stages << ") at t = " << std::setprecision(2) << t
+            << " (tn = " << tn << " , tcur = " << tcur << "), "
+            << std::setprecision(10)
+            << "||y||_2 = " << SUNRsqrt(N_VDotProd(y, y)) << "]" << std::endl
+            << std::flush;
+  return 0;
+}
+
+/*---- end of file ----*/
diff --git a/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_sprkstep.out b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_sprkstep.out
new file mode 100644
index 0000000000..1388944790
--- /dev/null
+++ b/test/unit_tests/arkode/CXX_serial/ark_test_stageinfo_sprkstep.out
@@ -0,0 +1,64 @@
+Start SPRKStep StageInfo test
+           t                        q1                       q2                     q3                       q4               
+------------------------------------------------------------------------------------------------------------------------------
+ 0.000000000000000e+00    4.000000000000000e-01    0.000000000000000e+00    0.000000000000000e+00    2.000000000000000e+00
+    [Pre-step processing at t = 0.00e+00 (tn = 0.00e+00 , tcur = 0.00e+00),||y||_2 = 2.0396078054e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 1.34e-04 (tn = 0.00e+00 , tcur = 0.00e+00), ||y||_2 = 2.0396078054e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 5.15e-04 (tn = 0.00e+00 , tcur = 1.34e-04), ||y||_2 = 2.0396079787e+00]
+    [Post-stage processing (stage 0 of 4) at t = 1.34e-04 (tn = 0.00e+00 , tcur = 1.34e-04), ||y||_2 = 2.0396081541e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = -9.03e-05 (tn = 0.00e+00 , tcur = 1.34e-04), ||y||_2 = 2.0396081541e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 4.30e-04 (tn = 0.00e+00 , tcur = -9.03e-05), ||y||_2 = 2.0396116094e+00]
+    [Post-stage processing (stage 1 of 4) at t = -9.03e-05 (tn = 0.00e+00 , tcur = -9.03e-05), ||y||_2 = 2.0396115204e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 6.66e-04 (tn = 0.00e+00 , tcur = -9.03e-05), ||y||_2 = 2.0396115204e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 8.71e-04 (tn = 0.00e+00 , tcur = 6.66e-04), ||y||_2 = 2.0396057340e+00]
+    [Post-stage processing (stage 2 of 4) at t = 6.66e-04 (tn = 0.00e+00 , tcur = 6.66e-04), ||y||_2 = 2.0396059367e+00]
+    [Pre-RHS processing (stage 3 of 4) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 6.66e-04), ||y||_2 = 2.0396059367e+00]
+    [Pre-RHS processing (stage 3 of 4) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.0396023491e+00]
+    [Post-stage processing (stage 3 of 4) at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03), ||y||_2 = 2.0396024276e+00]
+    [Post-step processing at t = 1.00e-03 (tn = 0.00e+00 , tcur = 1.00e-03),||y||_2 = 2.0396024276e+00]
+      1.0000000000e-03         3.9999687501e-01         1.9999947917e-03        -6.2499544275e-03         1.9999843751e+00
+    [Pre-step processing at t = 1.00e-03 (tn = 1.00e-03 , tcur = 1.00e-03),||y||_2 = 2.0396024276e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 1.13e-03 (tn = 1.00e-03 , tcur = 1.00e-03), ||y||_2 = 2.0396024276e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 1.52e-03 (tn = 1.00e-03 , tcur = 1.13e-03), ||y||_2 = 2.0396010553e+00]
+    [Post-stage processing (stage 0 of 4) at t = 1.13e-03 (tn = 1.00e-03 , tcur = 1.13e-03), ||y||_2 = 2.0396016098e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 9.10e-04 (tn = 1.00e-03 , tcur = 1.13e-03), ||y||_2 = 2.0396016098e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 1.43e-03 (tn = 1.00e-03 , tcur = 9.10e-04), ||y||_2 = 2.0396076483e+00]
+    [Post-stage processing (stage 1 of 4) at t = 9.10e-04 (tn = 1.00e-03 , tcur = 9.10e-04), ||y||_2 = 2.0396074962e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 9.10e-04), ||y||_2 = 2.0396074962e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 1.87e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.0395930192e+00]
+    [Post-stage processing (stage 2 of 4) at t = 1.67e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.0395935467e+00]
+    [Pre-RHS processing (stage 3 of 4) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 1.67e-03), ||y||_2 = 2.0395935467e+00]
+    [Pre-RHS processing (stage 3 of 4) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.0395861214e+00]
+    [Post-stage processing (stage 3 of 4) at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.0395862946e+00]
+    [Post-step processing at t = 2.00e-03 (tn = 1.00e-03 , tcur = 2.00e-03),||y||_2 = 2.0395862946e+00]
+      2.0000000000e-03         3.9998750018e-01         3.9999583342e-03        -1.2499635430e-02         1.9999375021e+00
+    [Pre-step processing at t = 2.00e-03 (tn = 2.00e-03 , tcur = 2.00e-03),||y||_2 = 2.0395862946e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 2.13e-03 (tn = 2.00e-03 , tcur = 2.00e-03), ||y||_2 = 2.0395862946e+00]
+    [Pre-RHS processing (stage 0 of 4) at t = 2.52e-03 (tn = 2.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.0395833769e+00]
+    [Post-stage processing (stage 0 of 4) at t = 2.13e-03 (tn = 2.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.0395843104e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 1.91e-03 (tn = 2.00e-03 , tcur = 2.13e-03), ||y||_2 = 2.0395843104e+00]
+    [Pre-RHS processing (stage 1 of 4) at t = 2.43e-03 (tn = 2.00e-03 , tcur = 1.91e-03), ||y||_2 = 2.0395929317e+00]
+    [Post-stage processing (stage 1 of 4) at t = 1.91e-03 (tn = 2.00e-03 , tcur = 1.91e-03), ||y||_2 = 2.0395927166e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 1.91e-03), ||y||_2 = 2.0395927166e+00]
+    [Pre-RHS processing (stage 2 of 4) at t = 2.87e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.0395695501e+00]
+    [Post-stage processing (stage 2 of 4) at t = 2.67e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.0395704024e+00]
+    [Pre-RHS processing (stage 3 of 4) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 2.67e-03), ||y||_2 = 2.0395704024e+00]
+    [Pre-RHS processing (stage 3 of 4) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.0395591399e+00]
+    [Post-stage processing (stage 3 of 4) at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03), ||y||_2 = 2.0395594079e+00]
+    [Post-step processing at t = 3.00e-03 (tn = 2.00e-03 , tcur = 3.00e-03),||y||_2 = 2.0395594079e+00]
+      3.0000000000e-03         3.9997187592e-01         5.9998593813e-03        -1.8748769629e-02         1.9998593855e+00
+------------------------------------------------------------------------------------------------------------------------------
+Current time                  = 0.003
+Steps                         = 3
+Step attempts                 = 3
+Stability limited steps       = 0
+Accuracy limited steps        = 0
+Error test fails              = 0
+NLS step fails                = 0
+Inequality constraint fails   = 0
+Initial step size             = 0.001
+Last step size                = 0.001
+Current step size             = 0.001
+f1 RHS fn evals               = 12
+f2 RHS fn evals               = 12
+End SPRKStep StageInfo test