diff --git a/app/serializers/user_serializer.rb b/app/serializers/user_serializer.rb
index 37dff62bb..6b32e83a1 100644
--- a/app/serializers/user_serializer.rb
+++ b/app/serializers/user_serializer.rb
@@ -2,6 +2,6 @@ class UserSerializer < ActiveModel::Serializer
   attributes :id, :name, :email, :locale, :ordergroup_name, :ordergroup_id
 
   def ordergroup_id
-    object.ordergroup.id
+    object.ordergroup ? object.ordergroup.id : -1
   end
 end