diff --git a/app/helpers/bulk_upload/sales_log_to_csv.rb b/app/helpers/bulk_upload/sales_log_to_csv.rb
index 79b136adb..cb31d9365 100644
--- a/app/helpers/bulk_upload/sales_log_to_csv.rb
+++ b/app/helpers/bulk_upload/sales_log_to_csv.rb
@@ -70,8 +70,7 @@ class BulkUpload::SalesLogToCsv
     when 2025
       (1..121).to_a
     when 2026
-      # TODO: CLDC-4162: Replace with actual field numbers when 2026 format is known
-      (1..121).to_a
+      (1..BulkUpload::Lettings::Year2026::CsvParser::FIELDS).to_a
     else
       raise NotImplementedError "No mapping function implemented for year #{year}"
     end