diff --git a/grudge/reductions.py b/grudge/reductions.py
index b86bccfbf79233f2872a3cf97b1e0d425c992a75..a1848bebc87ee5a41a9c0d51332122850235539d 100644
--- a/grudge/reductions.py
+++ b/grudge/reductions.py
@@ -248,7 +248,7 @@ def nodal_max_loc(dcoll: DiscretizationCollection, dd, vec) -> Any:
             vec, actx.from_numpy(np.array(-np.inf)))
 
 
-def integral(dcoll: DiscretizationCollection, dd, vec):
+def integral(dcoll: DiscretizationCollection, dd, vec) -> Any:
     """Numerically integrates a function represented by a
     :class:`~meshmode.dof_array.DOFArray` of degrees of freedom.