diff --git a/pint/quantity.py b/pint/quantity.py
index 138e17aa6..cfc5d93bf 100644
--- a/pint/quantity.py
+++ b/pint/quantity.py
@@ -771,6 +771,8 @@ def _get_reduced_units(self, units):
             if unit1 not in units:
                 continue
             for unit2 in units:
+                # get exponent after reduction
+                exp = units[unit1]
                 if unit1 != unit2:
                     power = self._REGISTRY._get_dimensionality_ratio(unit1, unit2)
                     if power:
diff --git a/pint/testsuite/test_quantity.py b/pint/testsuite/test_quantity.py
index b5413f4c1..998a53daa 100644
--- a/pint/testsuite/test_quantity.py
+++ b/pint/testsuite/test_quantity.py
@@ -642,6 +642,9 @@ def test_to_reduced_units(self):
             q.to_reduced_units(), self.Q_([3000.0, 4000.0], "ms**2")
         )
 
+        q = self.Q_(0.5, "g*t/kg")
+        helpers.assert_quantity_equal(q.to_reduced_units(), self.Q_(0.5, "kg"))
+
 
 class TestQuantityToCompact(QuantityTestCase):
     def assertQuantityAlmostIdentical(self, q1, q2):