diff --git a/chainladder/core/pandas.py b/chainladder/core/pandas.py
index 50179246..9d51741c 100644
--- a/chainladder/core/pandas.py
+++ b/chainladder/core/pandas.py
@@ -269,6 +269,26 @@ def fillna(self, value=None, inplace=False):
             new_obj = self.copy()
             return new_obj.fillna(value=value, inplace=True)
 
+    def fillzero(self, inplace=False):
+        """Fill nan with 0 by axis. separate function from fillna() because fillna(0) isn't working
+        Parameters
+        ----------
+        inplace: boolean, default = False
+            Whether to modify the triangle object directly (True), or
+            return a new modified triangle (False).
+
+        Returns
+        -------
+        Triangle
+        """
+        if inplace:
+            xp = self.get_array_module()
+            self.values = np.where((xp.nan_to_num(self.values) == 0) * (self.nan_triangle == 1), self.nan_triangle * 0, self.values)
+            return self
+        else:
+            new_obj = self.copy()
+            return new_obj.fillzero(inplace=True)
+
     def drop(self, labels=None, axis=1):
         """Drop specified labels from rows or columns.
 
diff --git a/chainladder/core/tests/test_triangle.py b/chainladder/core/tests/test_triangle.py
index 8ff5d638..8070ee6e 100644
--- a/chainladder/core/tests/test_triangle.py
+++ b/chainladder/core/tests/test_triangle.py
@@ -923,3 +923,9 @@ def test_OXDX_triangle():
                     #elif x in [6,3]:
                         #assert np.all(tri.origin.strftime('%Y') == pd.to_datetime(tri.odims).strftime('%Y'))
                         #assert np.all(tri.origin.strftime('%q').values.astype(float) == np.ceil((pd.to_datetime(tri.odims).strftime('%m').values.astype(int) - 0.5) / 3))
+
+def test_fillzero():
+    raa = cl.load_sample('raa')
+    zero = raa - raa[raa.origin=='1982']
+    filled = zero.fillzero()
+    assert (filled[filled.origin == '1982'][filled.development == 24].values.flatten()[0]) == 0
\ No newline at end of file