diff --git a/pint/compat.py b/pint/compat.py
index b968803ce..4b4cbab92 100644
--- a/pint/compat.py
+++ b/pint/compat.py
@@ -240,6 +240,8 @@ def _to_magnitude(value, force_ndarray=False, force_ndarray_like=False):
     "xarray.core.variable.Variable",
     "pandas.core.series.Series",
     "pandas.core.frame.DataFrame",
+    "pandas.Series",
+    "pandas.DataFrame",
     "xarray.core.dataarray.DataArray",
 )