diff --git a/flepimop/gempyor_pkg/tests/utils/test_utils.py b/flepimop/gempyor_pkg/tests/utils/test_utils.py
index 87e7c4fbb..5a434d299 100644
--- a/flepimop/gempyor_pkg/tests/utils/test_utils.py
+++ b/flepimop/gempyor_pkg/tests/utils/test_utils.py
@@ -37,7 +37,7 @@ def test_read_df_and_write_success(fname, extension):
     ("fname", "extension"), [("mobility", "csv"), ("usa-geoid-params-output", "parquet")]
 )
 def test_read_df_and_write_fail(fname, extension):
-    with pytest.raises(NotImplementedError, match=r".*Invalid.*extension.*Must.*"):
+    with pytest.raises(ValueError, match=r".*Invalid.*extension.*Must.*"):
         os.chdir(tmp_path)
         os.makedirs("data", exist_ok=True)
         os.chdir("data")