HMRC has published its latest round of updates to the Customs Declaration Service (CDS) codelists — versions 2.56 and 2.57. Together, the two releases bring new additions, corrections and structural changes across multiple codelists: a fresh validation code, a substantial batch of new document codes, five new Additional Information (AI) statement codes, and significant maintenance of the goods location (UN/LOCODE) list.
Codelist updates rarely make headlines, but they decide whether your declarations clear first time. A declaration built on an outdated codelist can be rejected outright — or, just as costly, miss a newer code that fits your movement better. Here is the full breakdown of what has changed, followed by what to check in your own filing workflow.
The ValidationResultTypes codelist — the catalogue of validation and error codes CDS can return when it checks a submitted declaration — has gained one new entry:
In practice this means CDS has a new way of telling you something is wrong (or needs attention) on a declaration. If your filing software has not incorporated the latest codelists, a response carrying an unrecognised code can surface as a generic or unexplained failure — which is far harder to troubleshoot than a properly mapped error.
If a declaration starts failing with an error you have not seen before, codelist drift is one of the first things to rule out. Validation rules evolve with every CDS release — your software (or provider) needs to keep pace.
This is the largest single area of change. Eighteen new document codes have been added to the DocumentTypes codelist and mapped across the relevant child codelists — ImportCertificates, ExportCertificates, StatusDocuments, NonStatusDocuments and ReasonDocuments — as applicable. These are the codes you quote in Data Element 2/3 to reference licences, certificates, waivers and statements against your goods items.
| Series | New Codes | Typically Used For |
|---|---|---|
| Y-series | Y081Y682Y683Y684Y685Y763Y770Y889 | Union statement and waiver-style codes — typically declaring that a particular measure, prohibition or restriction does not apply to the goods. |
| C-series | C127C128C129 | Union certificates, licences and authorisations referenced against the declared commodity. |
| U-series | U190 | Proofs of origin and preference-related documents. |
| National (9-series) | 9C019U089U099U109U119Y16 | UK national document codes, used where GB-specific documentary requirements apply. |
New document codes usually arrive because a new regulation, licensing regime or documentary requirement is coming into force — or because HMRC is refining how an existing requirement is declared. The exact usage conditions for each code (which commodities, which procedures, which measures) are defined in HMRC’s document code guidance, so always confirm the completion notes for a code before using it on a live declaration.
Five new Additional Information (AI) codes — also known as Special Mentions, declared in Data Element 2/2 — have been introduced. Each has a defined scope, so note carefully whether a code applies to imports, exports, or both:
AI statements carry information customs needs that has no dedicated data element of its own — and where a measure requires one, omitting it will stop a declaration from clearing. Applying a statement outside its scope — an export-only code on an import, or vice versa — will fail validation, so bake the scope into your templates from the start. As with document codes, each AI code comes with specific completion rules in HMRC’s Appendix 4 guidance: check the conditions before adding a new statement to your templates.
Significant maintenance has been carried out on the UnLocodes codelist — the goods location codes (GLCs) declared in Data Element 5/23 to identify exactly where goods can be examined. This release adds 42 new locations:
Scanning the list, you will spot the familiar three-letter hub codes embedded in many of the new entries — LHR (Heathrow), BHX (Birmingham), FXT (Felixstowe), BFS (Belfast), LIV (Liverpool), DOV (Dover), IMM (Immingham) and more — reflecting new sheds, depots and approved premises coming online around the UK’s major air and sea gateways.
Why it matters: the goods location code on a declaration must match a live entry on the CDS codelist and reflect where the goods will genuinely be available for examination. If a shed, ETSF or approved premises you use has just been added under a new code, declarations quoting an old or incorrect location can be rejected or held. Equally, a newly approved location near you may simplify a routing you currently work around.
Every role in the supply chain touches these codelists differently. Expand the section that fits you:
The goods location updates are the ones to watch. If the sheds, ETSFs or approved premises you deliver to have new GLCs, the declarations covering your loads need to quote them correctly — a wrong location code is a classic cause of goods being held at the frontier.
Check with your shed or inventory operator whether any of the new GBAU/GBCU codes above now applies to sites on your regular routes, and make sure whoever files your declarations knows.
Review your declaration templates. Saved templates are where stale codes hide: a template built last year will not know about the 18 new document codes or the 5 new AI statements, and may quote goods locations that have since been superseded.
Confirm your filing software is running the v2.56–2.57 codelists, and brief your entry clerks on the new codes — especially the import/export scope of each new AI statement, since applying an export-only statement to an import (or vice versa) will fail validation.
New document and AI codes usually track new regulatory requirements. If your commodities fall under evolving regimes, ask your broker (or check HMRC’s completion guidance) whether any of the new codes now applies to your goods — being early to a required statement is far cheaper than a rejected consignment.
If you self-file, make sure the platform you use keeps its codelists current, so new codes appear in your picklists the moment they are valid.
Ingest the updated codelists across ValidationResultTypes, DocumentTypes (and its child codelists — ImportCertificates, ExportCertificates, StatusDocuments, NonStatusDocuments, ReasonDocuments), the AI code list and UnLocodes.
Map the new validation code CDS11014 so it surfaces meaningfully to users rather than as an unknown error, and regression-test any local validation that mirrors HMRC’s rules.
Keeping pace with every CDS codelist release is exactly the kind of overhead the Customs Declarations UK platform is built to absorb. Codelists are maintained in line with HMRC’s releases, so the codes above are available where you would expect them — no patches to install, no spreadsheets of new codes to circulate around the team.
Whether you file CDS imports, CDS exports, GB ENS safety & security declarations, EU ICS2 or French ELO — on a simple pay-as-you-go basis, with no port badge required — the platform keeps the compliance plumbing current so your team can focus on the goods, not the codelists.
Taken together, CDS codelist versions 2.56 and 2.57 deliver four things: major UN/LOCODE maintenance, large-scale document code expansion, enhanced validation rules, and new Special Mention (AI) codes. None of it changes how you file — all of it changes what a correct filing contains.
Codelists are the vocabulary of CDS — and with v2.56–2.57 that vocabulary just grew, so make sure every declaration you submit is speaking the current version.