About

The independent reference for the UK CBAM.

Law as at 13 September 2026.

UK CBAM is an independent information service focused exclusively on the United Kingdom carbon border adjustment mechanism. We prioritise enacted legislation, statutory instruments and incorporated documents over guidance, and we distinguish clearly between law, guidance, draft notices and material awaiting publication.

The mechanism is the tax that the Finance Act 2026 charges from 1 January 2027 on the emissions embodied in imported aluminium, cement, fertilisers, hydrogen, and iron and steel goods. The site is written for the business that imports those goods into the United Kingdom: the finance director who has to accrue for the tax, the customs manager whose declarations decide whether a consignment is in scope, and the procurement manager who has to get emissions data out of a supplier abroad. It is also written for that supplier, who has received a request it did not expect.

What the site offers

The commodity code checker reads an eight-digit commodity code against the Table in Schedule 16 to the Finance Act 2026 and says whether goods under it are UK CBAM goods, which sector they fall in, and where a code is excepted or open to doubt. The registration threshold calculator applies the £50,000 test in Schedule 17 to the customs values a business enters, on both the look-back and the forward-looking limb, with the 2027 modification. The worked example runs one consignment from the customs declaration to the tax due on the default value, on verified emissions data and on the mixed route, with carbon price relief.

The guides answer the questions an importer asks: who is the importer when an agent, a group company or a delivered duty paid seller declares; which dates and deadlines run from 2026 to 2028; when to use actual emissions data and when a default value; which records to keep and for how long; who may verify emissions data and what the verification report must contain; how carbon price relief works and what form CarbonVP1 requires; which goods are outside the charge; what a producer outside the United Kingdom has to supply; how Northern Ireland is treated; and what the penalties, assessments and appeals are. The sector pages give the covered commodity codes, the exceptions, the system boundary and the supplier questions for each of the five sectors.

The rates and data pages are maintained references: the sectoral domestic price for each sector and quarter, the default values tracked until the Treasury publishes them, HMRC's list of qualifying carbon pricing schemes, and the status of every instrument and notice, from the Finance Act 2026 and the five statutory instruments through the System Boundaries Document to the draft force of law notices and the notices still awaited. The updates log every change in the law and the published material, dated and sourced, and say what changed, who is affected and what an importer should do now. The resources include the supplier question sheet and the document checklist as Word documents.

How information is checked

Every statement on the site is read in the primary source before it is written: the Finance Act 2026 on legislation.gov.uk, the Carbon Border Adjustment Mechanism regulations of 2026, the System Boundaries Document and HMRC's publications on gov.uk. The hierarchy of sources is enacted law, then statutory instruments, then the documents the instruments incorporate, then notices in force, then HMRC guidance, then draft notices. Guidance is named as guidance and law as law. A draft notice is never presented as law, a figure that has not been published is shown as not published rather than estimated, and every substantive page ends with a source status block giving the law it rests on and the date it was last reviewed. The site does not rewrite GOV.UK: GOV.UK states the rule, and this site says what the rule means for an importer, what changed, which document is needed, which calculation follows and what to do next.

The checker and the calculator run in the visitor's browser and send nothing anywhere. The site sets no cookies of its own, stores nothing a visitor types and takes no orders or payments. It describes a method and is not legal, tax or accounting advice, and no reader should file a return, claim a relief or take a position with HMRC on the strength of it alone.

The book

UK CBAM for UK Importers is the practitioner's guide from which the site's guides, sector pages and resources are drawn. It states the law as it stood on 13 September 2026 in twenty-eight chapters and five appendices, and every change after that date is logged on the updates page and on the errata page.

Corrections

A correction to any page is made on the page itself, with the review date updated, and a correction that changes what an importer should do is logged on the updates page. Corrections to the book are logged on the errata page. A reader who finds an error can write through the contact form.

Independence

This is an independent information service on the UK CBAM. It is not affiliated with HM Government or HMRC, it sells no consultancy, verification or filing service, and it names no company, product or process beyond the email service named in its privacy statement. The legal and privacy page gives that statement, the licence under which extracts from legislation and HMRC publications are reproduced, and the way to reach the service.