The CBAM definitive period: what actually changed on 1 January 2026
During the transitional period a CBAM report was an administrative task with no financial consequence. Since 1 January 2026 the same data sits behind a certificate purchase, an annual declaration and an independent verification opinion. This note sets out what changed, which instruments govern it, and what a non-EU installation has to be able to hand over.
From a reporting exercise to a priced obligation.
The transitional period ran from 1 October 2023 to 31 December 2025 and required quarterly reports of embedded emissions with no obligation to buy or surrender anything. The definitive regime replaced that arrangement on 1 January 2026 with four obligations that operate together: authorised CBAM declarant status before goods may be imported, an annual CBAM declaration, the purchase and surrender of CBAM certificates against the declared embedded emissions, and independent verification of those emissions by an accredited verifier.
Since 2026 the mechanism applies above a single mass threshold of 50 tonnes of CBAM goods per importer per year, and the first annual declaration — covering 2026 imports — falls due by 30 September 2027. Source: European Commission — CBAM definitive regime, checked 01 September 2026.
The practical consequence for a non-EU producer is that the number is no longer yours to state. It becomes an assertion examined against a written methodology by a body accredited for the purpose, and an assertion that cannot be supported is replaced by a default value that is unlikely to flatter you.
What governs the definitive period.
| Instrument | Date | What it governs |
|---|---|---|
| Regulation (EU) 2023/956 | 10 May 2023 | The framework: scope, declarant authorisation, declaration, certificates, verification requirement, Annex I and Annex II goods. |
| Implementing Regulation (EU) 2025/2547 | 10 December 2025 | Methods for calculating emissions embedded in goods: system boundaries, monitoring plan, actual values, default values, precursors, emissions report. |
| Implementing Regulation (EU) 2025/2546 | 10 December 2025 | Application of the verification principles: site visits, materiality levels and other parameters, format of the verification report. |
| Delegated Regulation (EU) 2025/2551 | 20 November 2025 | Conditions for granting accreditation to verifiers, control and oversight of accredited verifiers, withdrawal, mutual recognition and peer evaluation of accreditation bodies. |
What a non-EU installation has to be able to hand over.
A monitoring plan that existed before the reporting year
Implementing Regulation (EU) 2025/2547 requires the operator to design and implement a monitoring plan containing at least the elements set out in its Annex II. A plan written after the year has closed is a reconstruction, and a verifier will treat it as one.
Article 5A defined installation and defined production processes
Embedded emissions are attributed per production process and per good identified by CN code. Where the site makes several goods, the attribution rule between processes is the first thing examined and the most common source of restatement.
System boundaryActual data, or a documented reason why not
Default values are permitted only where actual values cannot be determined. Alternative default values require specific conditions to be satisfied and formal adoption before they may be applied.
Articles 11–12Precursor emissions traced to their source
A complex good carries the embedded emissions of its precursors. Actual emissions may be calculated for the good while default values are used for one or more precursors — but the split has to be documented, not assumed.
Article 15Electricity treated under its own conditions
Using actual values for electricity requires the operator to demonstrate that the conditions listed in Annex IV to Regulation (EU) 2023/956 are met, with documentary evidence.
Article 8An emissions report a third party can follow
The report must carry specific embedded emissions and the information that allows their accuracy to be verified — which in practice means the calculation must be reproducible from the primary records, not only from a spreadsheet.
Article 10
The numbers that set the verification effort.
Materiality
Implementing Regulation (EU) 2025/2546, Article 5(1)- For all installations producing CBAM goods: 5 % of the total specific embedded emissions.
- And 5 % of the total specific embedded free allocation.
- Applied per tonne of each relevant good, identified by CN code.
- Not differentiated by installation size or category.
Site visits
Implementing Regulation (EU) 2025/2546, Articles 2–4- A physical site visit is required in the first year.
- In later years it may be replaced by a virtual visit or waived where the stated conditions are met.
- A physical visit must take place at least every two years.
- Serious circumstances allow a virtual visit under separate conditions.
What a Gulf exporter should be doing in the current cycle.
The 2026 data year is already running. Whatever monitoring arrangement exists now is the arrangement that will be verified — a verifier examines what happened, not what was intended. Three things are worth settling before the year closes.
First, fix the boundary on paper. Which installation, which production processes, which CN codes, and how shared utilities and shared precursors are attributed between them. Nearly every restatement we see at this stage is a boundary question rather than an arithmetic one.
Second, decide actual-versus-default deliberately. Default values are a fallback, not a shortcut, and for a producer whose real intensity is below the default they are an avoidable cost carried by the customer. That decision has a data consequence, and the data has to be collected during the year.
Third, check the verifier, not the brochure. Accredited CBAM verification may only be performed within a granted scope by a body accredited by a national accreditation body of an EU country under the conditions of Delegated Regulation (EU) 2025/2551. A verifier who cannot show you a certificate and a scope covering your goods cannot sign your verification report, whatever else is true about them.
Primary sources
- Regulation (EU) 2023/956 establishing a carbon border adjustment mechanism — eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32023R0956 (checked 01 September 2026)
- Commission Implementing Regulation (EU) 2025/2547 of 10 December 2025 — methods for calculating emissions embedded in goods — eur-lex.europa.eu/eli/reg_impl/2025/2547/oj/eng (checked 01 September 2026)
- Commission Implementing Regulation (EU) 2025/2546 of 10 December 2025 — application of the principles for verification of declared embedded emissions — eur-lex.europa.eu/eli/reg_impl/2025/2546/oj/eng (checked 01 September 2026)
- Commission Delegated Regulation (EU) 2025/2551 of 20 November 2025 — accreditation, oversight and withdrawal for CBAM verifiers — eur-lex.europa.eu/eli/reg_del/2025/2551/oj/eng (checked 01 September 2026)
- Commission Implementing Regulation (EU) 2018/2067 — verification and accreditation under the EU ETS (materiality levels, Article 23) — eur-lex.europa.eu/eli/reg_impl/2018/2067/oj (checked 01 September 2026)
- European Commission — CBAM definitive regime — taxation-customs.ec.europa.eu/carbon-border-adjustment-mechanism/cbam-definitive-regime_en (checked 01 September 2026)
- European Commission — CBAM verification — taxation-customs.ec.europa.eu/carbon-border-adjustment-mechanism/cbam-verification_en (checked 01 September 2026)
- European Commission — guidance for the definitive period, published 14 August 2026 — taxation-customs.ec.europa.eu/news/european-commission-publishes-series-guidance-documents-support-cbam-implementation-definitive-2026-08-14_en (checked 01 September 2026)
- European Commission — guidance for verifiers and accreditation bodies, published 24 August 2026 — taxation-customs.ec.europa.eu/news/european-commission-publishes-guidance-cbam-verifiers-and-accreditation-bodies-2026-08-24_en (checked 01 September 2026)
Editorial note. Author and technical review above are editorial functions. They are separate from the independent technical review and the decision functions required under ISO/IEC 17029:2019, which apply to validation and verification engagements and not to published articles. Nothing on this page is advice on a specific engagement, and nothing here extends or replaces the accreditation records.
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