diff --git a/zipline/data/us_equity_pricing.py b/zipline/data/us_equity_pricing.py
index 12ec6a4b..57718438 100644
--- a/zipline/data/us_equity_pricing.py
+++ b/zipline/data/us_equity_pricing.py
@@ -41,7 +41,6 @@ from pandas import (
     DataFrame,
     DatetimeIndex,
     read_csv,
-    to_datetime,
     Timestamp,
 )
 from six import (