What Happened
HMRC has updated its Appendix 2 guidance on the Additional Procedure Codes used in Data Element 1/11 of the Customs Declaration Service. GOV.UK published the revision on 19 August 2026. The document sets out the completion rules for each 3-digit Union and National Additional Procedure Code that can be entered in DE 1/11 on an import declaration. It is the reference declarants use to confirm which code applies to a consignment, what conditions attach to it, and which supporting documents the entry must carry. The published summary does not itemise which individual codes changed.
Published: 19 August 2026 Source: GOV.UK HMRC
What the CDS Update Means for UK Importers
The practical issue here is version control. The Additional Procedure Code sits alongside the Procedure Code in DE 1/11 and shapes the duty and relief treatment applied to the goods, so working from a superseded code list can produce a rejected declaration or an entry that clears at the wrong rate. Anyone submitting entries directly, or reviewing work carried out on their behalf, should be reading the version HMRC published on 19 August 2026 rather than a saved internal copy. That matters most for standing declaration templates covering repeat shipments, where codes are copied forward month after month without anyone rechecking them.
This is maintenance of a live rule set rather than a single policy announcement, and it is the pattern importers have dealt with since CHIEF was withdrawn and CDS became the sole declaration platform. HMRC treats the CDS appendices as working documents and revises them as procedures, reliefs and statement codes change. The consequence is that the declaration rules a business validated when it first moved to CDS are not necessarily the rules in force now. For traders using inward processing, customs warehousing, returned goods relief or onward supply relief, DE 1/11 is where those regimes are actually claimed and evidenced.
The next step is a documented check rather than a one-off read. Confirm which Additional Procedure Codes your entries currently use, match each against the 19 August 2026 version of Appendix 2, and record the date of that check for audit purposes. Businesses that outsource UK import and customs clearance still carry the liability for what is declared in their name, so the review should cover broker templates as well as in-house ones. Errors found now can be corrected before goods arrive, which is considerably cheaper than a post-clearance amendment or a demand for underpaid duty.
Key Takeaway
Treat Appendix 2 as a document that changes, not a manual you read once. Check the codes on your live import entries against the current version, keep a dated record of the check, and make sure anyone declaring on your behalf is working from the same list.
Market Impact for UK Importers
The cost of getting DE 1/11 wrong is operational before it is financial. An entry rejected at validation holds the consignment at the frontier or in the temporary storage facility until it is resubmitted, and storage charges accrue while that happens. At Avonmouth and the other major container ports, free time on an arriving container is finite, so a declaration corrected 2 days late can turn into demurrage and detention on top of the original clearance issue.
The wider effect is on businesses claiming duty relief. Additional Procedure Codes are the mechanism by which relief regimes are declared, so an incorrect or outdated code can silently forfeit relief the business is entitled to, or claim one it cannot support on audit. Importers running inward processing or customs warehousing should expect HMRC to test code use against authorisation conditions, and the record of which guidance version was applied at the time of declaration becomes part of that defence.
