diff --git a/django/contrib/auth/admin.py b/django/contrib/auth/admin.py
index 81a963d015..b444fa5bac 100644
--- a/django/contrib/auth/admin.py
+++ b/django/contrib/auth/admin.py
@@ -62,11 +62,11 @@ class UserAdmin(admin.ModelAdmin):
         Use special form during user creation
         """
         defaults = {}
-        if not obj:
-            defaults = {
-                'form': UserCreationForm,
-                'fields': ['username'],
-            }
+        if obj is None:
+            defaults.update({
+                'form': self.add_form,
+                'fields': admin.util.flatten_fieldsets(self.add_fieldsets),
+            })
         defaults.update(kwargs)
         return super(UserAdmin, self).get_form(request, obj, **defaults)