diff --git a/src/__tests__/handleAction-test.js b/src/__tests__/handleAction-test.js
index caa43051..ca156547 100644
--- a/src/__tests__/handleAction-test.js
+++ b/src/__tests__/handleAction-test.js
@@ -19,6 +19,13 @@ describe('handleAction()', () => {
             counter: 7
           });
       });
+      it('returns default state if action is empty', () => {
+        const reducer = handleAction('NOTTYPE', () => null, { counter: 7 });
+        expect(reducer(undefined, {}))
+          .to.deep.equal({
+            counter: 7
+          });
+      });
 
       it('accepts single function as handler', () => {
         const reducer = handleAction(type, (state, action) => ({
diff --git a/src/handleAction.js b/src/handleAction.js
index 207f9071..800a8115 100644
--- a/src/handleAction.js
+++ b/src/handleAction.js
@@ -12,7 +12,7 @@ export default function handleAction(actionType, reducers, defaultState) {
     : [reducers.next, reducers.throw].map(reducer => (isNil(reducer) ? identity : reducer));
 
   return (state = defaultState, action) => {
-    if (!includes(actionTypes, action.type.toString())) {
+    if (action.type == null || !includes(actionTypes, action.type.toString())) {
       return state;
     }