Last updated: 16 October 2026
What is the Trader Support Service?
The Trader Support Service (TSS) is a free HMRC-funded service that helps businesses move goods between Great Britain and Northern Ireland, and into Northern Ireland from outside the UK, under the Windsor Framework. It completes customs and safety declarations on your behalf and offers guidance and training. A new TSS platform, operated by Netcompany and hosted on GOV.UK, replaces the old system: all goods movements on or after 20 October 2026 must be submitted on the new platform, so registered businesses need to pre-enrol before then.
Who should register?
- GB businesses sending goods to customers in Northern Ireland
- Northern Ireland businesses bringing goods in from GB or outside the UK
- Hauliers and intermediaries handling these movements
Movements of goods from Northern Ireland to GB generally need no customs declarations.
What TSS does
| Service | Detail |
| Customs declarations | Submitted on your behalf |
| Safety and security declarations | Entry summary declarations |
| Guidance | Help with the UK Internal Market Scheme and green lane |
| Training | Webinars and support |
| Cost | Free to use |
Green and red lanes
Under the Windsor Framework, goods staying in Northern Ireland can move through the green lane with simplified data if the business is registered for the UK Internal Market Scheme (UKIMS). Goods at risk of moving into the EU use the red lane, with full declarations and possible duty.
Steps to take now
- Watch for the invitation email from HMRC about the new platform.
2. Pre-enrol and set a new password.
3. Update your business details and user permissions.
4. Check you’re registered for UKIMS if you use the green lane.
5. Try the test environment before 20 October 2026.
Example
A Manchester online retailer sells clothing to customers in Belfast. It registers for UKIMS and uses TSS to submit simplified declarations through the green lane. When the new platform launches, it pre-enrols in early October, updates its details in 15 minutes and continues sending goods without delay.
VAT
Northern Ireland follows EU VAT rules for goods, so VAT registered businesses use XI VAT numbers when trading goods with the EU. Goods moving from GB to Northern Ireland are treated as domestic UK supplies for VAT.
Common mistakes
- Missing the switchover to the new platform
- Using the green lane without UKIMS authorisation
- Treating Northern Ireland as an export destination
- Forgetting safety and security declarations
Records to keep
Keep declaration references, UKIMS authorisation and commercial invoices.
The UK Internal Market Scheme
UKIMS authorisation lets businesses declare that goods are staying in Northern Ireland, so no EU tariffs apply and fewer data fields are needed. Applicants need to be established in the UK, have an XI EORI number and meet record-keeping conditions. Authorisation is usually quick if your records are in order.
Frequently asked questions
Does TSS cost anything?
No, it’s free.
Do I need an EORI number?
Yes, a GB or XI EORI as relevant.
Can my courier deal with it?
Many parcel carriers handle declarations for parcels.
Does it cover goods from the EU to Northern Ireland?
No declarations are needed for EU to NI goods.
Getting help
TSS offers phone and online support, and HMRC has contacted registered businesses with guidance and webinars.
Related: customs grants, the Import One Stop Shop and import VAT reviews.
Talk to Accotax
Want this handled for you? Our team at Accotax can help with GB to Northern Ireland trade help. See our small business accountants service, or contact us for a free, no-obligation quote.
This page is general guidance based on HMRC rules for the 2026/27 tax year, checked against gov.uk on 16 October 2026. It is not personal advice, so speak to an accountant about your own situation.
