In brief: The Carbon Border Adjustment Mechanism, or CBAM, puts a carbon-related cost on certain carbon-intensive goods traded across borders. The EU’s definitive CBAM regime began on 1 January 2026. A separate UK CBAM begins on 1 January 2027. Businesses should check the commodity codes of affected goods, identify who is the importer, and begin collecting value, weight, origin and emissions information before the first affected shipment.
What is CBAM
CBAM is intended to reduce carbon leakage. Carbon leakage can occur when production moves to a country with a lower carbon price, or when buyers replace domestically produced goods with more carbon-intensive imports. CBAM links the treatment of selected imports to the emissions created during their production.
For a logistics or customs team, the starting point is not a broad product description such as steel parts. Scope is determined by the relevant commodity code. Two products made from similar materials can fall under different codes and therefore receive different customs and CBAM treatment.
EU CBAM and UK CBAM are separate systems
UK businesses may encounter both regimes. The applicable system depends on where the goods are being imported, not simply where the seller is based.
| Point | EU CBAM | UK CBAM |
|---|---|---|
| Start date | Definitive regime from 1 January 2026 | Applies to specified imports from 1 January 2027 |
| Current sectors | Selected cement, iron and steel, aluminium, fertiliser, electricity and hydrogen goods | Selected aluminium, cement, fertiliser, hydrogen, iron and steel goods |
| Responsible party | The EU importer or, in relevant cases, its indirect customs representative | The importer named on, or represented by, the customs declaration |
| Threshold | More than 50 tonnes of CBAM goods for the mass-based authorisation threshold described by the European Commission | GBP 50,000 registration test using forward 30-day and backward 12-month assessments |
| Key action | EU importer reports embedded emissions and surrenders the required certificates | Registered importer keeps records, submits returns and pays the UK CBAM charge |
Only selected goods within these sectors are covered. The official commodity-code lists and current guidance must be checked for each product and trade route.
What EU CBAM means for a UK exporter
The legal obligation usually sits with the importer in the EU, but the UK exporter and the overseas producer may need to provide information that allows the importer to comply. This can include the commodity code, quantity, country of origin, production installation and embedded emissions data.
If the importer cannot obtain reliable information, it may need to use default values or take a more cautious commercial approach. In practice, that can affect the landed cost, the information requested before despatch, contract terms and the choice of supplier.
What UK CBAM means for a UK importer
Current GOV.UK policy states that the UK importer is the liable person. This is generally the person in whose name the customs declaration is made, or the person on whose behalf it is made. A tax agent may submit returns, but the importer must register and remains responsible for the liability.
The minimum registration threshold is GBP 50,000 of CBAM goods. This is not simply a once-a-year check. The importer must consider both a forward-looking test over the next 30 days and a backward-looking test over the previous 12 months. During the first year, businesses that become liable have until 31 January 2028 to register. The first accounting period runs from 1 January to 31 December 2027, with the first return and payment due by 31 May 2028 under current guidance.
Information importers should start collecting
- The correct commodity code for every potentially affected product.
- The customs value and net weight of each consignment.
- The non-preferential country of origin of the goods.
- The producer and installation where the goods were made.
- Verified actual emissions intensity data, where it is available.
- Evidence of any qualifying carbon price already paid in the country of production.
- Commercial invoices, customs declarations, calculation records and supplier correspondence.
The UK system will allow default emissions values where actual verified data is unavailable, but using defaults may produce a different liability from using verified production data. Businesses should decide early who will obtain, validate and retain the information.
Six practical preparation steps
1. Map imported and exported products to their current commodity codes. Do not rely only on product names or old invoices.
2. Compare those codes with the official EU or UK CBAM scope for the destination market.
3. Confirm the importer of record and the form of customs representation before agreeing delivery terms.
4. Ask affected suppliers for production and emissions data now, including the format and verification that will be available.
5. Create a consignment-level record that links the purchase order, invoice, commodity code, customs entry, value, weight, origin and emissions evidence.
6. Review quotations and contracts so responsibility for information, delays and additional costs is clearly allocated.
How CBAM affects transport and customs clearance
CBAM does not replace the normal customs declaration, commodity classification, valuation, origin or licensing requirements. It adds another reason to make sure the shipment data is complete and consistent before goods move.
A transport or customs provider can help coordinate movement and declarations, identify missing documents and make sure instructions reach the correct parties. The importer or exporter must still provide accurate product and origin information, and specialist tax or emissions advice may be required for complex cases.
Frequently asked questions
Does a UK exporter pay EU CBAM
Usually the EU importer, or an indirect customs representative in relevant cases, carries the EU obligation. However, the UK exporter may need to supply product, origin and emissions data. Commercial contracts may also pass some of the cost back through pricing.
Does CBAM apply to every steel or aluminium product
No. CBAM applies to selected goods identified by commodity code. Always check the current official list for the market into which the goods are being imported.
Is CBAM based on the emissions from the delivery vehicle
No. CBAM principally concerns emissions embodied in the production of covered goods. Transport emissions and a carrier’s fuel use are separate environmental considerations.
Can a customs agent take over all CBAM responsibility
An agent can assist with customs processes and, where permitted, act in a defined representative or tax-agent role. That does not automatically transfer every CBAM obligation. The importer should confirm the legal role and responsibility in writing.
What should a business do first
Start with the product list and commodity codes. Once potentially affected goods are identified, confirm the importer, review the threshold and begin collecting supplier and emissions evidence.
How Courier Express can help
Courier Express supports international transport and customs clearance for businesses moving goods into and out of the UK. We can help coordinate shipping instructions and customs documentation, identify information gaps before collection, and keep the parties involved in the movement informed. CBAM tax calculations and emissions verification may require advice from an appropriately qualified specialist.
If you are planning an international movement and want to check what information will be needed for transport and customs clearance, contact the Courier Express team before the goods are despatched.