On 16 October 2026 HMRC published the UK CBAM default values: 570 commodity codes across the five sectors, one value per code in tonnes of CO₂e per tonne of product. The value is the same whatever country the goods come from. HMRC says the values replicate the draft Default Values Force of Law notice, which puts them in force from 1 January 2027 to 31 December 2028. All 570 are now searchable on this site.
What the values look like
- Iron & steel: 478 codes, 0.494 to 9.121 tCO₂e/t
- Aluminium: 58 codes, 2.030 to 6.023
- Fertilisers: 27 codes, 0.457 to 3.247
- Cement: 6 codes, 0.240 to 2.075
- Hydrogen: 1 code, 28.378
HMRC built them from EU data, weighted to what the UK actually imports, with EU-origin data left out. Every sector carries a 10% markup except fertilisers, which has none. From 2029 the UK moves to country-specific values, one per good per country, and the markup is reviewed then. These are a different set from the EU's country-by-country default values, so expect the same product to carry a different number in each scheme.
The rule to know before you file
HMRC: if you submit a return that uses default values, you cannot amend it later with actual emissions data. Decide which route each good takes before the first return, due 31 May 2028. If your suppliers can give you verified actual data, ask now; the supplier data templates cover the request.
Illustrative rates, not binding ones
HMRC also published illustrative CBAM ratesper tonne of CO₂e: iron & steel £9.69, aluminium £9.79, cement £8.78, fertiliser £1.45 and hydrogen £9.24. They use the Q3 2026 average UK ETS price of £58.15 and the 2027 free-allocation phase-out factor of 97.5%. For cement, with 87.1% baseline free allocation: £58.15 × (1 − 87.1% × 97.5%) = £8.78.
HMRC is explicit that these create no liability and are not forecasts. The binding rates for January to March 2027 come out before the end of 2026, then by the start of every quarter. As a sense of scale only: a tonne of hot-rolled coil (7208 10 00) at its 2.722 default comes to about £26 at the illustrative steel rate.
What changed on this site
The UK default values page lists all 570 codes with the illustrative cost per tonne beside each. The UK CBAM overview and the UK vs EU comparisonare updated. The UK readiness pack's liability sheet now uses HMRC's values instead of the EU proxy, priced at the illustrative rates in cells you overwrite when the binding rates arrive. Earlier buyers get the new version from their download link.