Wholesalers registered with the Trader Support Service (TSS) have until 20 October to migrate to the new platform before HMRC shuts the door on new goods movements through the current system.

The TSS is a free-to-use digital platform that provides end-to-end support for businesses moving goods between Great Britain and Northern Ireland, helping them comply with the Windsor Framework. From 20 October, all goods movements taking place on or after that date must be submitted on the new platform. The current TSS will stop accepting new movements from that date.

The migration timetable is tight but structured. From 1 October, businesses currently using TSS will receive emails with instructions on how to pre-enrol for the new platform. They will also receive instructions for accessing a test environment where they can familiarise themselves with how the platform works before the cutover.

Gill Evans, HMRC's Director of customs services and operations, said: "We're working with businesses to make the move to the new Trader Support Service as straightforward as possible. Businesses should look out for their invitation email and pre-enrol before 20 October to ensure they can continue submitting declarations as normal.

"Once their details have been updated, they can familiarise themselves with the new platform. Support and guidance is available to help businesses switch."

For wholesalers trading across the Irish Sea, the operational stakes are straightforward. Any GB–Northern Ireland consignment not declared on the new platform after 20 October risks delay at the border, and border delay translates directly into longer lead times for customers, disruption to delivery schedules and potential inventory gaps on shelves in the North. Businesses that treat the migration as an administrative formality rather than a supply chain task may find the hard cutover catches them mid-week, mid-delivery cycle.

The three-week window between the first invitation emails on 1 October and the deadline on 20 October leaves limited time for businesses to test, train staff and adjust internal processes. HMRC's provision of a test environment acknowledges that the new platform will not be identical to the old one in workflow terms, and distributors would be well advised to use it with realistic shipment scenarios rather than waiting for live traffic to expose gaps.

The Windsor Framework context matters for channel economics. The framework governs the post-Brexit arrangements for goods moving between Great Britain and Northern Ireland, and the TSS exists to keep that flow administratively manageable for traders who do not necessarily run large customs operations in-house. For wholesalers, the platform is effectively the compliance backbone of east-west trade on the island of Ireland, and its replacement is a mandatory infrastructure change, not an optional upgrade.

The practical checklist for registered wholesalers is short. Watch for the invitation email from 1 October. Pre-enrol before 20 October. Use the test environment to rehearse declarations. Update business details as instructed. HMRC states that support and guidance are available throughout the switch, and businesses that engage early with that support will face less risk of disruption than those that leave enrolment to the final days.

What remains unclear from HMRC's announcement is how the new platform will handle the volume of declarations that flows through TSS, and whether any functional differences beyond the interface will affect how wholesalers prepare and submit movements. HMRC has not disclosed transaction volumes or detailed performance expectations for the replacement system. Those are asserted as improvements in due course; what is measured today is only the deadline itself.

With under three weeks between invitation and cutover, wholesalers moving goods between Great Britain and Northern Ireland should treat pre-enrolment as this month's priority compliance task.