diff --git a/membership/models.py b/membership/models.py
index e5454839..b572833d 100644
--- a/membership/models.py
+++ b/membership/models.py
@@ -96,7 +96,9 @@ def assign_username(user):
 
         # Try to come up with a username
         first_name, last_name = get_first_and_last_name(user.name)
-        user.username = unicodedata.normalize('NFKD', first_name + last_name).encode('ascii', 'ignore')
+        user.username = unicodedata.normalize(
+            'NFKD', first_name + last_name
+        ).encode('ascii', 'ignore').decode('ascii', 'ignore')
         user.username = "".join([char for char in user.username if char.isalnum()]).lower()
         if user.username.strip() == "":
             try: