diff --git a/chargebee/util.py b/chargebee/util.py
index bcc2504..b20237b 100644
--- a/chargebee/util.py
+++ b/chargebee/util.py
@@ -1,3 +1,6 @@
+import calendar
+from datetime import datetime
+
 from chargebee import compat
 
 def serialize(value, prefix=None, idx=None):
@@ -34,6 +37,8 @@ def get_val(val):
         return ''
     elif isinstance(val, bool):
         return str(val).lower()
+    elif isinstance(val, datetime):
+        return calendar.timegm(val.utctimetuple())
     else:
         if compat.py_major_v < 3 and isinstance(val, unicode): 
               return val.encode("utf-8")
diff --git a/tests/util.py b/tests/util.py
index 41bb308..311b4d7 100644
--- a/tests/util.py
+++ b/tests/util.py
@@ -1,5 +1,7 @@
 import unittest
 
+import datetime
+
 from chargebee import util
 
 
@@ -25,7 +27,8 @@ def test_serialize(self):
                 'expiry_month': '1',
                 'expiry_year': '2024',
                 'cvv': '007',
-            }
+            },
+            'starts': datetime.datetime(2017,01,10)
         }
 
         after = {
@@ -40,6 +43,7 @@ def test_serialize(self):
             'card[expiry_month]': '1',
             'card[expiry_year]': '2024',
             'card[cvv]': '007',
+            'starts': 1484006400,
         }
 
         self.assertEqual(after, util.serialize(before))