UK maritime port codes for customs declarations
HMRC has published the official location codes for maritime ports and wharves to be used in Data Element 5/23 of the UK Customs Declaration Service. These codes identify where goods may be examined upon import or export. Shippers and freight forwarders using CDS must reference the correct port code when filing maritime cargo declarations.
Photo: Wolfgang Weiser / Pexels# UK maritime port codes for customs declarations
On 6 May 2026, HMRC released guidance specifying the location codes required for Data Element 5/23 of the Customs Declaration Service (CDS). Data Element 5/23 designates the location where goods may be examined, and for maritime movements, these codes correspond to UK ports and wharves.
"Find the codes which can be used in Data Element 5/23 to identify the location where the goods may be examined for maritime ports and wharves (Appendix 16C)." — HMRC
The codes are set out in Appendix 16C of the guidance. This technical requirement applies to all maritime cargo declarations filed via CDS, including imports, exports, and transhipments through UK ports.
Data Element 5/23 is a mandatory field in the CDS and must match the actual port or wharf where examination may take place. Using an incorrect code can delay processing, trigger errors in CDS submission, and potentially result in penalties for non-compliance with declaration standards.
The specific port codes cover all operational maritime facilities across the UK, including major container ports, roll-on/roll-off terminals, breakbulk wharves, and specialist cargo handlers. Traders and forwarders must verify they are referencing the correct code for the port of loading, discharge, or transhipment before submission.
HMRC updates the port code list periodically as facilities open, close, or change operational status. The current version published in May 2026 supersedes any earlier guidance.
What this means for shippers
You must obtain and use the correct maritime port code from Appendix 16C when completing CDS declarations for any shipment moving through UK ports. Failure to use the accurate code will cause CDS validation errors and delays. Check the HMRC guidance immediately and update your freight management and customs systems with the current port codes for all UK ports you use. Assign one person to monitor HMRC updates to this list and notify your team when codes change.
