diff --git a/pandas/tests/scalar/period/test_asfreq.py b/pandas/tests/scalar/period/test_asfreq.py
index 597282e10052e..0c491786370a2 100644
--- a/pandas/tests/scalar/period/test_asfreq.py
+++ b/pandas/tests/scalar/period/test_asfreq.py
@@ -825,6 +825,7 @@ def test_asfreq_MS(self):
         with pytest.raises(ValueError, match=msg):
             initial.asfreq(freq="MS", how="S")
 
+        msg = "MonthBegin is not supported as period frequency"
         with pytest.raises(ValueError, match=msg):
             Period("2013-01", "MS")