UK CBAM from 2027: what exporters to Britain need to know
The UK starts its own carbon border tax on 1 January 2027. Who pays, the £50,000 threshold, the first deadlines, and how it differs from the EU CBAM.
Checked against the EU rules on 6 October 2026.
The UK starts its own Carbon Border Adjustment Mechanism on 1 January 2027. Like the EU CBAM, it charges for the emissions embedded in imported carbon-intensive goods. If you export to both the EU and the UK, your buyers on both sides will ask for the same kind of data.
Goods covered
Aluminium, cement, fertiliser, hydrogen, and iron and steel. Glass and ceramics, proposed earlier, are not in scope from 2027.
Who pays
The importer of the goods into the UK is liable, not you. As with the EU, the cost comes back to you in price talks, and your buyer will ask for emissions data that lowers it.
The £50,000 threshold
An importer must register with HMRC once it imports £50,000 or more of CBAM goods in the previous 12 months, or expects to within the next 30 days. Only goods imported from 1 January 2027 count. Smaller UK buyers stay outside. Note the difference: the EU threshold is 50 tonnes a year, the UK one is a value.
Dates
- 1 January 2027: UK CBAM starts; the government publishes a rate per sector at the start of each quarter.
- 31 January 2028: registration deadline for importers who became liable in 2027 (normally 30 days).
- 31 May 2028: return and payment for the whole of 2027, the first accounting period.
- From 2028: quarterly accounting periods.
EU and UK side by side
| Topic | EU CBAM | UK CBAM |
|---|---|---|
| Starts | 1 January 2026 | 1 January 2027 |
| Who pays | Authorised CBAM declarant (importer) | Importer |
| Threshold | 50 tonnes a year | £50,000 of goods |
| Price | Certificates at the EU ETS price | Tax at a rate set each quarter |
| First payment | 30 September 2027, for 2026 | 31 May 2028, for 2027 |
Emissions data and carbon price paid
UK importers can use verified actual emissions or default values published by the government. They can also claim carbon price relief where the emissions were already subject to a qualifying carbon price. The UK has its own emissions and verification regulations, so ask your UK buyer whether the figures and verification you prepare for the EU will be accepted as they are.
What to do now
- Ask your UK buyers whether they expect to pass the £50,000 threshold.
- Work out your own figure with the emissions calculator; the same records serve both markets.
- Send UK buyers the emissions summary in English.
Sources: GOV.UK CBAM policy summary (updated 9 September 2026) and work out the date you'll need to register (16 July 2026). UK rates and default values are published by the government; this page does not estimate them.
General information for planning, not legal, tax or customs advice. See the disclaimer.