diff --git a/src/pretix/base/orderimport.py b/src/pretix/base/orderimport.py
index c25b65a509..ed7a731256 100644
--- a/src/pretix/base/orderimport.py
+++ b/src/pretix/base/orderimport.py
@@ -836,7 +836,7 @@ class CustomerColumn(ImportColumn):
         if value:
             try:
                 value = self.event.organizer.customers.get(
-                    Q(identifier=value) | Q(email=value) | Q(external_identifier=value)
+                    Q(identifier=value) | Q(email__iexact=value) | Q(external_identifier=value)
                 )
             except Customer.MultipleObjectsReturned:
                 value = self.event.organizer.customers.get(