UK CBAM Administration Rules: SI 2026/802

Status at 16 July 2026: SI 2026/802 had been made and laid, and commencement is fixed for 1 January 2027. Later HMRC notices and emissions legislation may add operational requirements.

Many UK importers have treated CBAM as a problem that begins at registration. If you expect to stay below the registration trigger, the reasoning goes, there is nothing to build yet.

SI 2026/802 removes that comfort. The instrument turns several core record, registration and return requirements into final rules, and the central record duty is not limited to registered persons.

The record duty starts before registration does

If you import a CBAM good in the course of a business, you must record the commodity code and description, the import date, the value and the weight. The code is recorded at the 8-digit level.

That duty applies whether or not you are registered. It reaches an importer who sits below the registration trigger, and it reaches one who has not yet arrived at the point where registration becomes necessary.

Two of those fields have a prescribed measure. The basic weight measure is net of packing, measured at UK import and expressed in kilograms. Value follows the applicable UK customs-valuation route.

Retention splits in two. Records linked to an accounting period must generally be kept for 6 years from the day after that period ends. Other covered records run for 6 years from creation. All of them must be in writing.

The check to run this week is small. Open your customs data and confirm it holds an 8-digit code, a description, an import date, a customs value and a net weight for every business import that could be in scope.

Registration data and return data are not the same set

The registration dataset is the broader of the two. It covers identity and contact details, business form, EORI, any VAT number held, the trigger date and import-value information for the applicable test.

It also requires an estimate of import weight by CBAM sector over the following 12 months. You must retain the evidence supporting the information you supply.

The return fields specified in the instrument are narrower. For each charged CBAM good, the return currently requires the 8-digit commodity code, the weight, the carbon-price-relief amount and the place of origin. It must also carry a declaration that it is true and accurate to the maker's best knowledge.

Note what is absent. The instrument does not itself make emissions intensity, actual-versus-default status or precursor data part of that core return list.

That absence is not permanent. HMRC can require additional information by notice, and later emissions legislation may add fields.

If the weight record is wrong, an officer can set it

Origin follows the non-preferential customs-tariff rules identified in the instrument, and you must retain the supporting origin evidence.

Weight carries a sharper consequence. If the recorded weight is wrong, or the required weight record is missing, an HMRC officer may determine the weight.

The officer may work from estimates, assumptions, comparisons, inspection material or other evidence, and must notify the person in writing. The practical effect is that the weight used against you can be set by someone other than you.

Reimbursement: 90 days, no fee, no deduction

The regulations also prescribe conditions for reimbursement arrangements. Reimbursement must be completed within 90 days, without a fee or deduction, and in the manner prescribed by HMRC.

If the sum is not reimbursed, it and the related interest must be repaid to HMRC. That repayment falls due 14 days after the end of the 90-day period.

What to do before 1 January 2027

Start with the import-data gap check described above. Confirm that your systems retain the required code, description, import date, customs value, net weight and origin evidence for every business import that may be in scope.

Then keep two evidence files rather than one. Registration evidence and return evidence are not identical datasets, and merging them makes it harder to show which record supported which submission.

Assign one named owner to monitor HMRC notices before any live registration or return is prepared. The notice power is the route by which further fields will arrive.

Do not add expected emissions fields to a checklist you are treating as final law. Mark them as pending until the legislation or notice that requires them is published.

Source note: This article is based on the as-made text of SI 2026/802 at the official legislation.gov.uk locator. Recheck that source, and any HMRC notices issued under the instrument, immediately before operational use.

Source

Source publication: The Carbon Border Adjustment Mechanism (Administrative Provisions) Regulations 2026

Source status/class: Made statutory instrument; made 13 July 2026, laid before the House of Commons 14 July 2026, in force 1 January 2027