diff --git a/src/pretix/plugins/stripe/payment.py b/src/pretix/plugins/stripe/payment.py
index a0f7275d91..79af9a71d3 100644
--- a/src/pretix/plugins/stripe/payment.py
+++ b/src/pretix/plugins/stripe/payment.py
@@ -664,7 +664,7 @@ class StripeMethod(BasePaymentProvider):
             return
         d = json.loads(obj.info)
         new = {}
-        if 'source' in d:
+        if d.get('source'):
             new['source'] = {
                 'id': d['source'].get('id'),
                 'type': d['source'].get('type'),