CBAM Registration: How to Register with HMRC

Any UK-established person (individual or business) who imports CBAM-covered goods with a total CIF value exceeding £50,000 in a calendar year must register with HMRC. The importer of record — the entity named on the customs declaration — is the party responsible for registration.

If you use a customs agent or broker, they act on your behalf for customs clearance, but CBAM liability sits with you as the importer of record. You are the one who must register with HMRC, not your agent.

Registration is per legal entity. If your business has multiple UK-incorporated entities, each one that crosses the threshold must register separately.

The registration timeline depends on when you first exceed the threshold:

• If you exceed £50,000 during 2027, you must register by 31 January 2028
• If you exceed £50,000 in any subsequent year, you must register within 30 days of exceeding it
• Proactive registration is permitted — you can register before you exceed the threshold if you expect to do so

Missing the registration deadline carries financial penalties. HMRC has indicated it will apply a risk-based approach to enforcement, but intentional non-compliance or persistent failure to register is likely to attract significant penalties.

To register with HMRC for CBAM, you will need the following information ready:

• Your company name, registered address, and Companies House number
• Your Economic Operators Registration and Identification (EORI) number
• Contact details for the person responsible for CBAM compliance
• Estimated annual tonnage of CBAM-covered imports by sector
• The customs procedure codes (CPCs) you use for importing covered goods
• Details of any customs agent or broker you authorise to act on your behalf

HMRC is expected to provide a dedicated CBAM registration portal within the Government Gateway system. If your business already has a Government Gateway account for VAT or customs purposes, you can use the same credentials.

Registration is expected to follow this sequence:

• Log in to Government Gateway and navigate to the CBAM service
• Complete the registration form with your business details and EORI number
• Declare the CBAM sectors relevant to your imports (aluminium, cement, fertiliser, hydrogen, iron and steel)
• Provide estimates of import volumes for the current and next calendar year
• Confirm your authorised representative for CBAM matters
• Submit and receive your CBAM registration number

Once registered, you will receive a CBAM registration number distinct from your EORI number. Keep this number accessible — you will need it for every CBAM return you file.

HMRC has committed to processing registrations within 30 working days. In practice, straightforward registrations may complete faster, but you should not leave registration until the last working day before the deadline.

Once registered, you become a CBAM declarant. This means:

• You must file CBAM returns for each reporting period (annually initially, quarterly from 2030)
• You must retain records supporting your emissions calculations for six years
• HMRC may audit your CBAM data and supporting evidence
• You must update your registration if your business details change or you cease importing covered goods

Registration is not a one-off event. You remain registered until you formally notify HMRC that you have ceased importing CBAM-covered goods or fallen permanently below the threshold.