diff --git a/google_auth_oauthlib/helpers.py b/google_auth_oauthlib/helpers.py
index 19c34b6..d32864d 100644
--- a/google_auth_oauthlib/helpers.py
+++ b/google_auth_oauthlib/helpers.py
@@ -137,6 +137,6 @@ def credentials_from_session(session, client_config=None):
         client_id=client_config.get('client_id'),
         client_secret=client_config.get('client_secret'),
         scopes=session.scope)
-    credentials.expiry = datetime.datetime.fromtimestamp(
+    credentials.expiry = datetime.datetime.utcfromtimestamp(
         session.token['expires_at'])
     return credentials