NCTS6 Phase 1 Implementation and Downtime

The New Computerised Transit System, Phase 6 (NCTS6) will be delivered in two phases. NCTS6 Phase 1 is scheduled for deployment on Monday, 1 September 2025.

Planned downtime - 1 September 2025

To support the deployment of NCTS6 Phase 1, there will be a short period of downtime affecting both the Great Britain (GB) and Northern Ireland (XI) NCTS services:

Both Great Britain (GB) and Northern Ireland (XI) services will be unavailable from 21:00 BST on 1 September 2025. Both services are expected to be fully restored by 23:00 BST.

Messages relating to submitted declarations during this time will be queued and issued once the services have been restored.

Important information during downtime

Please ensure you follow the usual procedures for exports and imports, such as getting a Goods Movement Reference if moving via a GVMS location.

For departures, whilst NCTS is unavailable, we recommend avoiding movements under the normal procedure, which requires attendance at Inland Border Facilities (IBFs) or ports.

If you must move goods and cannot submit declarations before the downtime begins, you may use the manual fallback procedure. However, we advise against travelling to an IBF to start a transit movement until the system is back online.

For arrivals into GB or XI you should continue your movements as usual. Some transit processes such as office of destination may need to be completed when NCTS is available.

You can find the manual fallback processes in the Transit Manual Supplement.

Need Help?

If you require urgent support during this time, please contact: -

• NCTS Helpdesk - ncts.helpdesk@hmrc.gov.uk or 0300 322 7095
• NCTS Supervising Office - isbc.nctssupervisingoffice@hmrc.gov.uk or 0300 322 9452.

What’s changing in NCTS6 Phase 1?

NCTS6 Phase 1 is primarily a Migration Pathway release that does not impact on customers, ahead of the full NCTS6 Phase 2 deployment (date to be confirmed). It also includes fixes for several known issues in NCTS5:

• Unloading Remarks Timestamp Issue: Currently, unloading remarks submitted between 00:00 and 01:00 BST are incorrectly treated as future dated. This will be resolved, eliminating the need for the workaround of using the previous day’s date.
• National Transit Write-Off Issue: When the same trader handles both arrival and departure, the CC045 message is incorrectly linked to the arrival identifier. This will be corrected.
• Reusable Local Reference Numbers (LRNs): NCTS currently rejects LRNs that have been cancelled and reused. This restriction will be lifted.
• Unloading Remarks Rejections for Multiple House Consignments: When adding goods items sequentially within consignments, the system currently expects the sequence to follow the total number of goods items. This will be fixed, and the current workaround will no longer be necessary.
• Successful message regeneration: You will now be able to ask the NCTS Helpdesk to re-send a transit message that has already been successfully sent.

Note: Your software provider may have implemented temporary workarounds for some or all of these issues. Please contact them directly to understand how your system will operate after 1 September.

What’s next?

HMRC will issue communications and update our service availability page to confirm when NCTS6 Phase 1 is live.