diff --git a/modules/utility/init.zsh b/modules/utility/init.zsh
index caa0ec8d41..eeaa00dda7 100644
--- a/modules/utility/init.zsh
+++ b/modules/utility/init.zsh
@@ -118,13 +118,17 @@ alias ll='ls -lh'        # Lists human readable sizes.
 alias lr='ll -R'         # Lists human readable sizes, recursively.
 alias la='ll -A'         # Lists human readable sizes, hidden files.
 alias lm='la | "$PAGER"' # Lists human readable sizes, hidden files through pager.
-alias lx='ll -XB'        # Lists sorted by extension (GNU only).
 alias lk='ll -Sr'        # Lists sorted by size, largest last.
 alias lt='ll -tr'        # Lists sorted by date, most recent last.
 alias lc='lt -c'         # Lists sorted by date, most recent last, shows change time.
 alias lu='lt -u'         # Lists sorted by date, most recent last, shows access time.
 alias sl='ls'            # I often screw this up.
 
+# Only make alias if ls supports -XB (darwins BSD style ls doesn't)
+if ls -XB &> /dev/null; then
+  alias lx='ll -XB'        # Lists sorted by extension (GNU only).
+fi
+
 # Grep
 if zstyle -t ':prezto:module:utility:grep' color; then
   export GREP_COLOR='37;45'           # BSD.