diff --git a/src/jade/post/manipulate_tally.py b/src/jade/post/manipulate_tally.py
index 5edf8d86..7c36e01a 100644
--- a/src/jade/post/manipulate_tally.py
+++ b/src/jade/post/manipulate_tally.py
@@ -342,11 +342,6 @@ def volume(tally: pd.DataFrame, volumes: dict[int, float]) -> pd.DataFrame:
                 tally["Value"] / volumes[cell],
                 tally["Value"],
             )
-            tally["Error"] = np.where(
-                (tally["Cells"] == cell),
-                tally["Error"] / volumes[cell],
-                tally["Error"],
-            )
     return tally
 
 
@@ -373,11 +368,6 @@ def mass(tally: pd.DataFrame, masses: dict[int, float]) -> pd.DataFrame:
                 tally["Value"] / masses[cell],
                 tally["Value"],
             )
-            tally["Error"] = np.where(
-                (tally["Cells"] == cell),
-                tally["Error"] / masses[cell],
-                tally["Error"],
-            )
     return tally
 
 
diff --git a/tests/post/test_manipulate_tally.py b/tests/post/test_manipulate_tally.py
index 114a46c9..0ce0fc83 100644
--- a/tests/post/test_manipulate_tally.py
+++ b/tests/post/test_manipulate_tally.py
@@ -390,7 +390,7 @@ def test_volume():
     volumes = {1: 2.0, 2: 2.0, 3: 2.0, 4: 2.0, 5: 2.0}
     result = volume(df, volumes)
     assert 3.65062e-06 == pytest.approx(result["Value"][0], rel=1e-5)
-    assert 0.05 == pytest.approx(result["Error"][0], rel=1e-5)
+    assert 0.1 == pytest.approx(result["Error"][0], rel=1e-5)
 
 
 def test_mass():
@@ -403,4 +403,4 @@ def test_mass():
     masses = {1: 2.0, 2: 2.0, 3: 2.0, 4: 2.0, 5: 2.0}
     result = mass(df, masses)
     assert 3.65062e-06 == pytest.approx(result["Value"][0], rel=1e-5)
-    assert 0.05 == pytest.approx(result["Error"][0], rel=1e-5)
+    assert 0.1 == pytest.approx(result["Error"][0], rel=1e-5)