diff --git a/src/pretix/base/services/cart.py b/src/pretix/base/services/cart.py
index ceb623a07..342562efb 100644
--- a/src/pretix/base/services/cart.py
+++ b/src/pretix/base/services/cart.py
@@ -109,7 +109,7 @@ def _add_new_items(event: Event, items: List[dict],
         voucher = None
         if i.get('voucher'):
             try:
-                voucher = Voucher.objects.get(code=i.get('voucher'), event=event)
+                voucher = Voucher.objects.get(code=i.get('voucher').strip(), event=event)
                 if voucher.redeemed:
                     return error_messages['voucher_redeemed']
                 if voucher.valid_until is not None and voucher.valid_until < now_dt:
diff --git a/src/pretix/presale/views/cart.py b/src/pretix/presale/views/cart.py
index fc992787e..5491ca24c 100644
--- a/src/pretix/presale/views/cart.py
+++ b/src/pretix/presale/views/cart.py
@@ -226,7 +226,7 @@ class RedeemView(EventViewMixin, TemplateView):
         from pretix.base.services.cart import error_messages
 
         err = None
-        v = request.GET.get('voucher')
+        v = request.GET.get('voucher').strip()
 
         if v:
             try: