Carbon Border Adjustment Mechanism (CBAM)
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CBAM's New Rulebook
On 24 August 2026, the European Commission published new Guidance on CBAM verification and accreditation, addressed to verifiers and National Accreditation Bodies. The 141-page document sets out how the definitive verification and accreditation rules apply to CBAM goods imported into the EU from 1 January 2026 onward. It is currently available in English only; a French version will follow.
For importers of steel, aluminium, cement, fertilizers, hydrogen, or electricity, this guidance determines whether a supplier’s actual emissions data can be used in a CBAM declaration, or whether the applicable default value plus its associated mark-up will apply instead.
CBAM places a carbon price on imports of these six product categories, calibrated to match the carbon price EU producers already pay under the EU Emissions Trading System. Its definitive phase, established by Regulation (EU) 2023/956 (as amended by Regulation (EU) 2025/2083), started on 1 January 2026. It is a mechanism intended to prevent carbon leakage and support fair competition between EU and non-EU producers.
Importers submit annual declarations based either on actual verified emissions data or on default emissions values. Actual emissions count only where they have been verified by an independent body accredited under Regulation (EC) No 765/2008 by an EU/EEA National Accreditation Body.
Verification at installation level. A supplier certificate alone is not sufficient evidence. Verifiers must assess how the non-EU installation defines its production boundary, measures emissions, and controls the underlying data. Where a single installation report covers several products, the verifier also checks that each product is correctly matched to its combined nomenclature (CN) code, production route, and calculation boundary.
A high assurance bar. Verifiers are required to assess the completeness, consistency, comparability, accuracy, and integrity of emissions data, with professional scepticism, independence, and impartiality treated as essential requirements.
A structured accreditation cycle. Requirements include competence assessments, office and witness audits, five-year accreditation periods, annual surveillance reviews, and lead-auditor rotation.
Registry access as the operational gatekeeper. From 1 September 2026, accredited verifiers can access the CBAM Registry and must register within two months of receiving accreditation (not before that date). From January 2027, verification reports will be issued directly in the Registry, which is what allows importers to use actual verified emissions in their CBAM declarations. The first CBAM verifiers are expected to receive accreditation around September 2026.
The guidance itself creates no new legal obligation: it clarifies how the existing rules apply, while leaving the emissions methodology, default values, and reporting deadlines unchanged.
For 2026 imports, authorised declarants must submit their first annual declaration by 30 September 2027. Working back from that date, industry analysis of the guidance suggests verified reports should reach declarants by mid-August, allowing time to assemble the declaration and purchase certificates, and recommends that verification start during the reporting year rather than after production data are closed. This is presented as an operational reading of the guidance rather than a deadline stated explicitly by the Commission.
Verification guidance is closely linked to a separate cost question. Where verified data is not available, importers must use default values set for the country of origin, plus a mark-up. Both are defined in Implementing Regulation (EU) 2025/2621, which was corrected by Implementing Regulation (EU) 2026/1740, published on 31 July 2026 and applicable retroactively from 1 January 2026. The mark-up varies by sector: for aluminium, cement, and iron and steel, it rises from 10% in 2026 to 30% in 2028; for fertilizers, reflecting supply-chain complexity, it remains at 1%.
Several industry trackers report specific default values, by product and country, that run above what verified data from efficient producers would typically show. Individual figures should be checked against the official IR 2025/2621 annexes, the Commission’s authoritative source, before being cited or relied upon. The Commission also provides the corrected values in an Excel file. That file is for information purposes only; the legally binding values remain those in the regulation, and a consolidated version is expected soon.
The August guidance moves CBAM’s definitive phase from stated rules to defined verification practice. That means installation-level audits, documented scepticism, five-year accreditation cycles, and a registry that now determines who can issue a valid verification report. For importers, whether a supplier’s emissions are ultimately priced on verified data or on a marked-up default may depend on whether an accredited verifier is engaged in the coming months.
Looking for an independent verifier for your suppliers’ 2026 emissions data? Normec Verifavia, a COFRAC-accredited verification body, is in process of becoming CBAM accredited, contact us at [email protected].
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