Steel moving from the European Union to the United Kingdom after an initial EU import could face separate carbon assessments once the UK carbon border mechanism begins in 2027, creating additional requirements for emissions evidence and cost allocation across the two jurisdictions.
The issue arises where steel enters the EU and is subsequently re-exported to Britain. Carbon Pulse reported on the potential interaction between the two systems on 22 September. The situation does not mean that every re-export will automatically incur two complete and unreduced carbon charges.
The treatment of carbon costs under the UK system depends on whether a qualifying overseas carbon price has actually been borne and can be demonstrated under the applicable rules.
UK relief depends on eligible carbon prices
HM Revenue & Customs (HMRC) provides relief for qualifying overseas carbon prices that have been effectively paid. Its published list includes the EU Emissions Trading System (EU ETS) but does not expressly name the EU CBAM.
HMRC states that its list is non-exhaustive, meaning that the absence of EU CBAM from the published list does not, by itself, constitute a definitive determination that payments under the mechanism cannot qualify.
Recognition of a carbon-pricing scheme is separate from establishing the amount that can be deducted from a UK liability. Free allowances do not constitute an effective carbon price for this purpose, while rebates and other forms of compensation can reduce the relief available.
Evidence requirements affect re-export calculations
HMRC guidance requires independently verified carbon-pricing information when calculating eligible relief. Qualifying amounts must also be converted into sterling using the prescribed exchange rates, and the relief cannot exceed the corresponding UK liability.
A commercial invoice identifying an EU carbon surcharge is therefore not necessarily sufficient evidence for a UK deduction. Such an invoice may reflect a supplier’s estimate without demonstrating which emissions were priced, which carbon-pricing system applied or whether the documentation required by HMRC exists.
The distinction becomes relevant for steel distributors using European warehouses before onward shipment to Britain. Information generated or held by the original importer or supplier may not remain with the entity responsible for the subsequent UK carbon border return.
Contracts need to separate carbon charges from tax relief
For traders, the resulting exposure is both administrative and financial. A carbon-related amount shown in the purchase chain may appear in a shipment’s cost calculation but fail to qualify as a deductible amount under the UK mechanism if the relevant conditions are not met or the payment cannot be substantiated.
Re-export arrangements therefore need to distinguish between a carbon cost charged commercially by a supplier and a carbon-price amount that the UK destination authority will recognise as eligible relief. The treatment of the two is not established simply because the first charge appears on an invoice.
