Free instant check
Does UK CBAM catch your business?
From 1 January 2027 the UK's carbon border tax applies to importers of iron & steel, aluminium, cement, fertiliser and hydrogen above a £50,000 rolling threshold. Answer three questions for an instant read on your position and your deadlines.
Customs value of the covered goods only — not your total import spend.
Runs entirely in your browser — nothing you enter is sent anywhere. Indicative only, based on the enacted Finance Act 2026 and draft regulations (reviewed 4 July 2026); not tax advice.
How the threshold actually works
The £50,000 minimum registration threshold is set by the Finance Act 2026 (Schedule 17), and it runs on two tests. The backward-looking test runs on the first day of every month: if the customs value of covered goods you imported over the preceding 12 months is £50,000 or more, you've triggered registration. The forward-looking test bites on any day you expect £50,000+ of covered goods within the next 30 days — so a single large shipment can put you in scope from day one, before any look-back builds up.
Only covered goods count: the statutory commodity-code list spans the five sectors but has real edges — scrap and most ferro-alloys are out, while downstream products like screws, bolts and aluminium structures are in. Our sector-by-sector guide walks the list, and the threshold deep-dive has worked examples of exactly when different import patterns trigger.
If you trigger during 2027, registration is due by 31 January 2028, and your first return — covering the whole of 2027 — lands with payment by 31 May 2028. The data in that return is collected during 2027, which is why the useful preparation starts with your suppliers, not with HMRC.
Threshold questions, answered
How does the £50,000 UK CBAM threshold work?
Two statutory tests, and meeting either one triggers registration. Backward-looking: on the first day of each month, if your covered goods imported over the preceding 12 months total £50,000 or more, you're in. Forward-looking: on any day you expect to import £50,000 or more of covered goods within the next 30 days, you're in immediately. In 2027 the look-back only reaches to 1 January 2027.
What value counts towards the threshold?
The customs value of the covered goods only — the same value used to work out customs duty. Your total import spend is irrelevant; only goods on the CBAM commodity-code list count.
When would I have to register?
Normally within 30 days of triggering the threshold. For the first year there's an easement: anyone who triggers at any point during 2027 has until 31 January 2028 to register with HMRC.
Are scrap metal imports caught?
No — ferrous waste and scrap and aluminium scrap are outside the statutory goods list. But check your commodity codes carefully: remelt products and downstream goods are covered, and mixed consignments can still take you over the threshold.
Does the threshold apply per company or per group?
Per legal entity — there is no group aggregation. Each company that meets the tests registers and files separately. The legislation also contains anti-avoidance rules against artificially splitting a business to stay under £50,000.