diff --git a/users/serializers.py b/users/serializers.py
index df33adf3b7..0e583de015 100644
--- a/users/serializers.py
+++ b/users/serializers.py
@@ -439,7 +439,7 @@ class ChangeEmailRequestUpdateSerializer(serializers.ModelSerializer):
     @transaction.atomic
     def update(self, instance, validated_data):
         """Updates an email change request"""
-        if User.objects.filter(email=instance.new_email).exists():
+        if User.objects.filter(email__iexact=instance.new_email).exists():
             log.debug(
                 "User %s tried to change email address to one already in use", instance
             )