diff --git a/script/import_scripts/generic.rb b/script/import_scripts/generic.rb
index 5ea539fa5c..5efd3caeee 100644
--- a/script/import_scripts/generic.rb
+++ b/script/import_scripts/generic.rb
@@ -366,7 +366,8 @@ class ImportScripts::Generic < ImportScripts::Base
       post_type: post_type,
       action_code: "split_topic",
       import_mode: true,
-      created_at: to_datetime(row["created_at"])
+      created_at: to_datetime(row["created_at"]),
+      custom_fields: { import_id: row["id"] }
     )
   end