diff --git a/tests/test_assets.py b/tests/test_assets.py
index eeecd487..9fed193f 100644
--- a/tests/test_assets.py
+++ b/tests/test_assets.py
@@ -961,6 +961,14 @@ class TestFutureChain(TestCase):
             pd.Timestamp(feb_prev, tz='UTC')
         )
 
+        # Test that the as_of() method works with str args
+        feb_str = '2006-02-01'
+        cl_feb = cl.as_of(feb_str)
+        self.assertEqual(
+            cl_feb.as_of_date,
+            pd.Timestamp(feb, tz='UTC')
+        )
+
         # The chain as of the current dt should always be the same as
         # the defualt chain.
         self.assertEqual(cl[0], cl.as_of(pd.Timestamp('2005-12-01'))[0])
diff --git a/zipline/assets/futures.py b/zipline/assets/futures.py
index 9e71bd6a..12dcae52 100644
--- a/zipline/assets/futures.py
+++ b/zipline/assets/futures.py
@@ -162,7 +162,7 @@ class FutureChain(object):
             asset_finder=self._asset_finder,
             get_datetime=self._algorithm_get_datetime,
             root_symbol=self.root_symbol,
-            as_of_date=dt
+            as_of_date=Timestamp(dt, tz='UTC'),
         )
 
     def offset(self, time_delta):