1. Ten new guidelines to support the implementation of the CBAM
On 14 August 2026, the European Commission published ten guidance documents, primarily aimed at operators of production installations located outside the European Union, as well as authorised CBAM declarants and verifiers.
The series comprises four general guidance documents addressing, in particular, the fundamental principles of the mechanism, the methods for calculating embedded emissions and the adjustment for free allocation under the EU Emissions Trading System (EU ETS). These are complemented by six sector-specific guides covering cement, hydrogen, fertilisers, iron and steel, aluminium and electricity.
Through practical examples, these documents help operators understand the requirements applicable since 1 January 2026 and prepare their first annual CBAM declarations.
Although not legally binding, the guidance documents provide valuable clarification on the application of the regulatory framework, particularly Commission Implementing Regulations (EU) 2025/2547 and 2025/2620.
2. Calculation methods for embedded emissions: further clarification
Guidance Document No. 3, dedicated to the calculation of embedded emissions, outlines the main changes introduced between the transitional period (2023–2025) and the definitive phase of the CBAM.
The calculation methodology is now subject to more standardised rules, taking into account emissions generated by production processes and, depending on the goods concerned, indirect emissions arising from electricity consumption and emissions embedded in input materials known as “precursors”.
Several developments deserve particular attention:
- Reporting period: The reference period is now aligned with the calendar year of production, subject to specific rules for determining the relevant reporting period for imported goods.
- Units of measurement: The applicable functional units have been further specified, notably by reference to clinker content for cement and nitrogen content for certain fertilisers.
- Treatment of precursors: New rules govern the attribution and calculation of emissions embedded in precursors, including the use of weighted averages where multiple suppliers or production periods are involved.
- Production processes: The boundaries of production processes and the conditions governing the calculation and attribution of direct and indirect emissions are now more clearly defined.
Record-keeping requirements have also been strengthened, with the mandatory retention period for emissions monitoring data extended from four to six years.
In practice, these clarifications highlight the need for greater traceability throughout industrial production processes and more reliable emissions data from non-EU suppliers.
3. Calculating CBAM certificate obligations: actual emissions, default values and free allocation
Authorised CBAM declarants may determine the embedded emissions of imported goods using either verified actual emissions data or default values established by the European Commission.
The use of actual emissions data requires detailed information on production installations, together with a verification report issued by an accredited verifier. Where such data are unavailable, importers may rely on the applicable default values, which include mark-ups designed to account for uncertainties in emissions calculations.
Guidance Document No. 4 also explains how to calculate the adjustment reflecting the emission allowances still allocated free of charge to EU producers under the EU Emissions Trading System (EU ETS).
The number of CBAM certificates to be surrendered is therefore determined on the basis of the embedded emissions of imported goods, taking into account the adjustment for free allocation and, where applicable, the carbon price effectively paid in the country of origin, in accordance with the applicable regulatory requirements.
The choice of calculation method is therefore a significant financial consideration for importers, as the emissions values used may directly affect their CBAM liability.
The sale of CBAM certificates will begin on 1 February 2027, through a common central platform, in accordance with Article 20 of Regulation (EU) 2023/956, as amended by Regulation (EU) 2025/2083. Certificates purchased in 2027 to cover imports made in 2026 will be priced according to the quarterly CBAM certificate price applicable to the period in which the goods were imported.
The first annual CBAM declaration, covering imports made in 2026, must be submitted, and the corresponding CBAM certificates surrendered, by 30 September 2027.
4. Revised default values with retroactive effect
Commission Implementing Regulation (EU) 2026/1740 of 20 July 2026, published on 31 July 2026, introduces corrections to several default values established for the definitive phase of the CBAM. These corrections apply retroactively from 1 January 2026.
For goods in the cement, iron and steel, aluminium and hydrogen sectors, the default values used to calculate the number of CBAM certificates to be surrendered are subject to a mark-up of 10% in 2026, 20% in 2027 and 30% from 2028 onwards. For fertilisers, a flat mark-up of 1% applies throughout the period.
On 10 August 2026, the Commission also made available an updated spreadsheet of default values, providing operators with a practical reference tool for applying the revised figures.
Importers should therefore reassess their estimated CBAM costs where these were calculated using the previously published default values.
5. Further clarification on emissions verification
On 24 August 2026, the European Commission published new guidance on CBAM verification and accreditation.
These documents clarify the accreditation requirements applicable to verifiers, the procedures for verifying emissions data and the arrangements for submitting verification reports.
Since 1 September 2026, accredited verifiers have been able to apply for access to the CBAM Registry. From January 2027, they will be able to issue verification reports through the Registry.
For importers intending to rely on actual emissions data, anticipating verification requirements and ensuring close cooperation with non-EU suppliers are therefore essential steps towards CBAM compliance.
6. French customs authorities take a tougher stance on CBAM declaration errors
In France, in a notice published on 23 October 2026, the French Directorate-General of Customs and Indirect Taxes (DGDDI) announced that the initial period of guidance and awareness-raising following the introduction of the CBAM is drawing to a close. The DGDDI warns that certain errors in import declarations can no longer be treated as mere inaccuracies and may, depending on their nature and implications, constitute customs offences and give rise to penalties.
Importers must, in particular, use their SIREN-based EORI number (EORI SIREN), including when claiming an exemption, ensure that the information provided in their customs declarations matches the details associated with their CBAM account, and use the appropriate customs codes reflecting their specific circumstances.
The DGDDI specifically highlights the requirement for authorised CBAM declarants to use code Y128, the use of code Y137 when claiming the exemption based on the annual 50-tonne threshold, and the exceptional nature of code Y238, which remains available only to a limited number of operators specifically identified by the European Commission. Code Y422 must also be used when placing goods covered by the CBAM under the inward processing procedure.
7. Financial obligations becoming a reality
On 5 October 2026, the European Commission published the CBAM certificate price for the third quarter of 2026, set at €82.32, up from €75.28 in the second quarter.
CBAM certificate prices are calculated and published quarterly in 2026, before switching to weekly pricing from 2027 onwards.
Importers will be required to submit their first annual CBAM declaration, covering imports made in 2026, and surrender the corresponding CBAM certificates by 30 September 2027.
Meanwhile, discussions at EU level are continuing on the proposed extension of the CBAM to certain downstream products containing steel or aluminium from 2028 onwards.
These developments confirm that CBAM compliance is no longer limited to reporting requirements. Importers must now ensure the reliability of their emissions data, review their contractual arrangements with suppliers and anticipate the carbon costs associated with their imports.
8. Downstream products: proposed extension of CBAM from 2028
In its legislative proposal of 17 December 2025, the European Commission proposes to extend the scope of the CBAM from 1 January 2028 to approximately 180 categories of downstream products with a high steel or aluminium content, including certain fasteners, wires, springs and manufactured articles. The proposed extension aims to mitigate the risk of carbon leakage further down the value chain.
On 12 June 2026, the Council of the European Union adopted its negotiating position, expanding the proposed scope to approximately 200 product categories. The European Parliament subsequently adopted its amendments on 15 September 2026, by 464 votes in favour, 50 against and 159 abstentions, advocating an even broader extension of the mechanism.
Interinstitutional negotiations, which began in autumn 2026, are also addressing additional anti-circumvention measures, the treatment of metal scrap and the rules governing default values.
9. China: a potential obstacle to the transfer of carbon emissions data
On 26 October 2026, China’s Ministry of Commerce (MOFCOM) launched a public consultation, open until 24 November 2026, on draft special provisions for the protection of Chinese trade secrets. Article 2 targets foreign entities involved in infringements of Chinese trade secrets where such conduct harms, or poses an actual threat to, China’s sovereignty, security or development interests. Under Article 5, MOFCOM could, in particular, restrict or prohibit certain international trade activities and services involving the entities concerned.
For CBAM purposes, this proposal raises the possibility of a blockage in the flow of carbon emissions data. The calculation and verification of actual embedded emissions require access to detailed information on industrial processes, energy consumption and raw materials at installations outside the EU. Some of that information may be commercially sensitive. If its disclosure to foreign importers or verifiers were challenged on trade secret grounds, a broad application of the future rules could make the transfer of such data difficult, or even practically impossible, for certain Chinese supply chains.