diff --git a/arraycontext/container/traversal.py b/arraycontext/container/traversal.py
index fe486781..a7aebdcd 100644
--- a/arraycontext/container/traversal.py
+++ b/arraycontext/container/traversal.py
@@ -866,7 +866,10 @@ def _to_numpy_with_check(subary: Any) -> Any:
                     f"array of type '{type(subary).__name__}' not in "
                     f"supported types {actx.array_types}")
 
-    return rec_map_array_container(_to_numpy_with_check, ary)
+    return rec_map_array_container(_to_numpy_with_check,
+                                   # do a freeze first, if 'actx' supports
+                                   # container-wide freezes
+                                   thaw(freeze(ary, actx), actx))
 
 # }}}