Two systems, one Irish Sea
Both the UK and Ireland have created a barcode-style reference that links a vehicle, a sailing and the customs declarations behind the load. They serve the same conceptual purpose — give the port authority a single thing to scan — but they live in different systems and are operated by different agencies.
- GMR (Goods Movement Reference) — created on HMRC's GVMS, used at UK RoRo ports and the Channel Tunnel. Required to board a ferry departing from or arriving at a GVMS-controlled UK port.
- PBN (Pre-Boarding Notification) — created on Revenue's Customs RoRo system, used at Irish ports (Dublin, Rosslare, Cork). Required to board a ferry sailing into an Irish port.
A round trip from Dublin to Holyhead and back
Say you're running a trailer from Dublin to Birmingham and back.
Dublin → Holyhead (outbound):
- You need a PBN on the Irish side because the trailer is departing an Irish port.
- The PBN links your Irish export declaration (AES) to the specific vehicle and sailing.
- At Holyhead you need a GMR on the UK side because the trailer is arriving at a UK port.
- The GMR links your UK import declaration (CDS) and safety and security entry (S&S GB) to the vehicle.
Holyhead → Dublin (return):
- You need a GMR on the UK side because the trailer is departing a UK port.
- The GMR links your UK export declaration to the vehicle.
- At Dublin you need a PBN on the Irish side because the trailer is arriving at an Irish port.
- The PBN links your Irish import declaration (AIS) and ICS2 safety and security entry to the vehicle.
Miss either reference and the driver does not board. Miss both and you're re-writing the day.
Channel colour
PBNs are channelled at the ramp: green, orange or red. Green means go; orange means documentary check; red means physical inspection. If you don't know your channel before the ramp, the driver will be the last to find out — and usually at the worst time.
GMRs don't use the same channel system, but the underlying declarations can still go into query, which has the same effect: the driver sits.
How we handle it
For every UK–Ireland round trip we prepare both references together, pair each to the underlying declaration before the cut-off, and monitor status right up to arrival. If a PBN channels red or a GMR goes into query, one call to our bilingual team and we work it until the vehicle is released.
Request a quote and tell us the route, volume and sailing window.