diff --git a/jax/_src/state/indexing.py b/jax/_src/state/indexing.py
index 716520c55..2544644d9 100644
--- a/jax/_src/state/indexing.py
+++ b/jax/_src/state/indexing.py
@@ -139,11 +139,12 @@ class NDIndexer:
         if value := _maybe_concretize(start):
           if value >= s:
             raise ValueError(f"Out of bound slice: start={value}, dim={s}.")
-          if value + (idx.size - 1) * idx.stride >= s:
-            raise ValueError(
-                f"Out of bound slice: start={value}, size={idx.size},"
-                f" stride={idx.stride}, dim={s}."
-            )
+          if size := _maybe_concretize(idx.size):
+            if value + (size - 1) * idx.stride >= s:
+              raise ValueError(
+                  f"Out of bound slice: start={value}, size={size},"
+                  f" stride={idx.stride}, dim={s}."
+              )
         continue
       # The shape of indexer integers should be broadcastable up to the
       # int_indexer_shape of the whole NDIndexer