From the definitive phase, embedded-emissions data behind a CBAM declaration needs independent verification — not just internal sign-off.
Last verified: 02 September 2026
Actual, supplier-specific embedded-emissions data lowers your CBAM obligation compared to a default value — which creates an obvious incentive to report favourable numbers. Independent verification is the check against that: an ISO 17029-accredited body reviews the evidence behind the figures before they can be used in a declaration, the same discipline EU ETS already applies to domestic installations.
Verification isn't a rubber stamp on a spreadsheet total — it traces the number back to its source:
| Verification step | What it checks |
|---|---|
| Monitoring plan | Whether the operator's data-collection method is defined and consistently applied |
| Source data | Raw activity data (fuel use, production volume, electricity consumption) behind the claimed figure |
| Calculation methodology | Whether the SEE formula (EU IR 2025/2547) was applied correctly to that source data |
| Material misstatement check | Whether the reported figure is free of errors large enough to change the CBAM outcome |
The Commission published its full verification guidance on 24 August 2026 — a 141-page document setting out the verification process in detail. Verifiers can register in the CBAM Registry from 1 September 2026 onward.
If you're an importer relying on a supplier's verified actual data, confirm your verifier has completed CBAM Registry registration under this timeline — a verification performed before registration opened isn't automatically invalid, but registry registration is the step that makes a verifier's status checkable by a customs authority.
An independent verifier accredited under ISO 17029 (Conformity assessment — General principles and requirements for validation and verification bodies) — the same accreditation standard used for EU ETS verification.