diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 6da55483f..52cbf3fc0 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -15,7 +15,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]
+        python-version: ["3.11", "3.12", "3.13"]
         os: [ubuntu-latest]
 
     steps:
diff --git a/pyproject.toml b/pyproject.toml
index c4aca1300..300efa9fa 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -9,7 +9,7 @@ build-backend = "setuptools.build_meta"
 name = "boutdata"
 description = "Python package for collecting BOUT++ data"
 readme = "README.md"
-requires-python = ">=3.9"
+requires-python = ">= 3.11"
 classifiers = [
     "Programming Language :: Python",
     "Intended Audience :: Science/Research",
@@ -32,10 +32,10 @@ authors = [{name = "Ben Dudson", email = "benjamin.dudson@york.ac.uk"}, {name =
 urls = {project = "https://github.com/boutproject/boutdata"}
 dependencies = [
     "sympy>=1.5.1",
-    "numpy>=1.22.0",
-    "matplotlib>=3.2.1",
+    "numpy >= 1.26.0",
+    "matplotlib >= 3.8.0",
     "natsort>=8.1.0",
-    "scipy>=1.4.1",
+    "scipy >= 1.12.0",
     "netCDF4",
 ]
 dynamic = ["version"]