UK CBAM guidance
UK CBAM emissions data: what to ask suppliers for
You may use actual emissions only when the relevant data has been verified by a qualifying verifier. Otherwise, HMRC requires the use of a default value.
Last updated: 13 August 2026
What actual emissions data means
For actual emissions, the liable person needs emissions-intensity information from the producer, expressed in tonnes of carbon dioxide equivalent per functional unit, together with evidence that it has been verified by a qualifying verifier. The exact monitoring and verification guidance is still being developed by HMRC.
What your import record needs to connect
| Import-side data | Supplier-side data | Why the link matters |
|---|---|---|
| 8-digit CBAM commodity code | Product and production route | Shows which imported good the emissions value applies to. |
| Net weight at import | Emissions intensity | Forms the basis of embodied-emissions calculation. |
| Tax-point date | Monitoring period and verification date | Supports selection of a valid emissions value. |
| Country of origin | Carbon-price evidence, if any | Supports potential carbon-price relief. |
Questions for a supplier
- Can you provide product-specific emissions intensity for UK CBAM goods?
- Which calendar-year monitoring period does it cover?
- Who verified the data, and can you share the report or summary?
- Does the evidence identify precursor inputs where relevant?
- Has the product been subject to a qualifying carbon price, and is there evidence?
Plan for the default route too
Defaults are an explicit part of the regime, not a filing failure. If actual data is absent or you do not have verification evidence, HMRC says a default value must be used. Create a supplier-data status for every in-scope product: verified actual, requested, unavailable, or default needed.
Record retention: HMRC says you must keep the verification report or verification summary relevant to actual emissions reported for six years.