diff --git a/netbox/extras/models/customfields.py b/netbox/extras/models/customfields.py
index 017e65c24..24d808c03 100644
--- a/netbox/extras/models/customfields.py
+++ b/netbox/extras/models/customfields.py
@@ -823,27 +823,31 @@ class CustomFieldChoiceSet(CloningMixin, ExportTemplatesMixin, ChangeLoggedModel
             raise ValidationError(_("Must define base or extra choices."))
 
         # check if removing any used choices
-        original_choices = [obj[1] for obj in self._original_extra_choices]
-        new_choices = [obj[1] for obj in self.extra_choices]
-        diff_choices = list(set(original_choices) - set(new_choices))
-        if diff_choices:
-            # CustomFields using this ChoiceSet
-            for custom_field in self.choices_for.all():
-                for object_type in custom_field.object_types.all():
-                    # unfortunately querying the whole array of diff_choices doesn't work
-                    for choice in diff_choices:
-                        # Need to OR query as can be multiple choice or single choice so
-                        # have to do both contains and equals to catch both
-                        query_args = {
-                            f"custom_field_data__{custom_field.name}__contains": choice,
-                            f"custom_field_data__{custom_field.name}": choice
-                        }
-                        if object_type.model_class().objects.filter(models.Q(**query_args, _connector=models.Q.OR)).exists():
-                            raise ValidationError(
-                                _("Cannot remove choice {choice} as it is used in model {model}").format(
-                                    choice=choice, model=object_type
+        if self._original_extra_choices:
+            original_choices = new_choices = []
+            original_choices = [obj[1] for obj in self._original_extra_choices]
+            if self.extra_choices:
+                new_choices = [obj[1] for obj in self.extra_choices]
+
+            diff_choices = list(set(original_choices) - set(new_choices))
+            if diff_choices:
+                # CustomFields using this ChoiceSet
+                for custom_field in self.choices_for.all():
+                    for object_type in custom_field.object_types.all():
+                        # unfortunately querying the whole array of diff_choices doesn't work
+                        for choice in diff_choices:
+                            # Need to OR query as can be multiple choice or single choice so
+                            # have to do both contains and equals to catch both
+                            query_args = {
+                                f"custom_field_data__{custom_field.name}__contains": choice,
+                                f"custom_field_data__{custom_field.name}": choice
+                            }
+                            if object_type.model_class().objects.filter(models.Q(**query_args, _connector=models.Q.OR)).exists():
+                                raise ValidationError(
+                                    _("Cannot remove choice {choice} as it is used in model {model}").format(
+                                        choice=choice, model=object_type
+                                    )
                                 )
-                            )
 
     def save(self, *args, **kwargs):