Hydrogen default values

Published 16 October 2026

This publication is licensed under the terms of the Open Government Licence v3.0 except where otherwise stated. To view this licence, visit nationalarchives.gov.uk/doc/open-government-licence/version/3 or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: psi@nationalarchives.gov.uk.

Where we have identified any third party copyright information you will need to obtain permission from the copyright holders concerned.

This publication is available at https://www.gov.uk/government/publications/check-the-default-values-for-the-carbon-border-adjustment-mechanism-cbam/hydrogen-default-values

Use this guidance to find the default values to use for the hydrogen sector. The values apply to each Carbon Border Adjustment Mechanism (CBAM) good, regardless of origin.

If you submit a CBAM return that uses default values, you cannot amend it later with actual emissions data.

The default values are sorted by combined nomenclature (CN) code. To find out the CN code for a good, you can use the Trade Tariff tool.

Using default values and actual emissions

You can use default values to determine emissions in your CBAM goods, including any CBAM goods used to make a final CBAM good (precursors).

You can use default values for precursor goods when using actual emissions data for relevant processes associated with turning the precursor goods into final CBAM goods.

You cannot use actual emissions data for precursor CBAM goods and default values for the final CBAM good.