CBAM Implementing Regulations: Complete List of All 13 Secondary Acts

CBAM implementing regulations total 13 secondary acts adopted between August 2023 and December 2025, filling the operational detail that the primary regulation, Regulation (EU) 2023/956, delegates to the European Commission. Each act targets a specific compliance mechanism: reporting formats, registry procedures, authorization criteria, emissions calculation methods, certificate pricing, and verifier accreditation. Understanding which act governs which obligation is the first step toward structured compliance with EU CBAM.

The 13 acts divide into two functional generations. The first generation (2023 to 2024) established transitional-period infrastructure. The second generation (2025) built the definitive-phase machinery that operates from January 1, 2026 onward. The sections below present the complete list, grouped by function, followed by answers to the most common questions about how CBAM secondary legislation works in practice.

Caption: All 13 CBAM implementing regulations span August 2023 to December 2025, with 11 of the 13 acts adopted in 2025 ahead of the definitive phase start.

What Are the CBAM Implementing Regulations?

CBAM implementing regulations are legally binding Commission acts that specify the procedural and technical details necessary to operate Regulation (EU) 2023/956. They do not create new obligations beyond the primary regulation; they define how those obligations are met. Each act is adopted under specific articles of Regulation (EU) 2023/956 that grant implementing powers to the Commission.

The primary regulation for EU CBAM establishes the framework: which goods are covered, who must comply, what a CBAM declaration contains, and what penalties apply. The implementing regulations convert that framework into operational instructions. For example, Article 7 of Regulation (EU) 2023/956 requires embedded emissions to be calculated according to a specified methodology. IR 2025/2547 is the act that defines that methodology in full, including system boundaries, monitoring plans, and the specific equations used for each sector.

Two of the 13 acts are technically delegated regulations rather than implementing regulations. DR 2025/2551 on verifier accreditation was adopted under a delegated power rather than an implementing power, which gives it slightly different legal status. For compliance purposes, the distinction is procedural; both types of secondary act carry the same binding force.

The EU carbon border adjustment mechanism as a whole therefore rests on 2 primary regulations plus these 13 secondary acts, with 2 further proposals pending co-legislator approval as of April 2026.

Complete List of All 13 CBAM Implementing Regulations

The table below presents all 13 secondary acts in chronological order. The regulation number, adoption date, Official Journal reference, and scope are drawn directly from the Official Journal of the European Union.

What Each Implementing Regulation Covers

IR 2023/1773: The Transitional Reporting Framework

IR 2023/1773 governed the entire transitional period from October 1, 2023 to December 31, 2025. It established quarterly reporting, defined 3 accepted calculation methods (actual emissions, default values, and alternative methods based on third-country carbon pricing systems), and set up the CBAM Transitional Registry. This act is now historical: its quarterly reporting obligations, the alternative calculation method, and the transitional-period penalties of €10–50 per tonne CO₂e no longer apply in the definitive phase that began January 1, 2026.

IR 2024/3210: Registry Infrastructure

IR 2024/3210 defines the CBAM Registry's technical and procedural architecture. It specifies account types, access management rules, data retention periods, and the authentication mechanism via UUM&DS (the same identity management system used by the EU ETS registry). This regulation applies from December 31, 2024 and underpins all registry operations, including authorization management and the certificate surrender process. IR 2025/2550 subsequently updated it for definitive-phase certificate management.

IR 2025/486: Authorized Declarant Authorization

IR 2025/486 operationalizes Articles 4 and 17 of Regulation (EU) 2023/956 for the EU CBAM authorization process. It defines the complete application package, sets the 120-day maximum decision timeline, lists grounds for refusal, specifies revocation conditions, and requires competent authorities to verify 5 years of customs and tax compliance history. IR 2025/2549 amended this act in December 2025 to incorporate the changes introduced by the Omnibus regulation.

IR 2025/2546 and IR 2025/2547: Verification and Calculation

These two acts form the technical core of the definitive phase. IR 2025/2546 sets the verification principles: when a site visit to the non-EU production installation is mandatory (it is mandatory for the first verification period), what a verification report must contain, and the independence requirements for verifiers. IR 2025/2547 defines the calculation methodology for CBAM embedded emissions, including monitoring plan requirements, system boundaries, direct versus indirect emission boundaries, and the sector-specific calculation equations. Compliance teams working through embedded emissions data for the first CBAM declaration in September 2027 rely on IR 2025/2547 as the primary technical reference.

IR 2025/2548: Certificate Price Calculation

IR 2025/2548 defines how the CBAM certificate price is derived from EU ETS auction prices. For 2026, the price is the quarterly average of EU ETS auction clearing prices. From 2027 onward, it switches to the weekly average of EU ETS auction closing prices. The Commission publishes the applicable price on a defined schedule. This distinction between quarterly averaging (2026) and weekly averaging (2027 onward) matters for financial planning: the 2026 method smooths short-term ETS volatility, while the 2027 method tracks market movements more closely.

IR 2025/2619, 2025/2620, and 2025/2621: Customs Integration and Default Values

Three acts adopted on December 16, 2025 complete the definitive-phase operational layer.

IR 2025/2619 establishes the data exchange protocol between EU customs authorities and the CBAM Registry. Customs offices transmit import declaration data in real time, enabling automatic verification that the importer holds valid authorization at the moment of import.

IR 2025/2620 codifies the SEFA (Specific Embedded Free Allocation) methodology, which calculates the CBAM certificate reduction attributable to EU ETS free allocation received by competing domestic EU producers. This act implements the free allocation phase-out schedule that runs from 2026 (CBAM factor: 2.5%, free allocation remaining: 97.5%) through to 2034 (CBAM factor: 100%, free allocation: 0%).

IR 2025/2621 sets the default embedded emission values for the definitive phase. It provides country-specific and product-specific emission intensity defaults for all 6 CBAM sectors, with a punitive mark-up applied on top of the calculated default: 10% above the calculated default in 2026, 20% in 2027, and 30% from 2028 onward. Fertilizers receive a flat mark-up of 1% in each year rather than the 10/20/30 schedule, reflecting agricultural price sensitivity. IR 2025/2621 applies from January 1, 2026.

DR 2025/2551: Verifier Accreditation

DR 2025/2551 is the delegated regulation governing verifier accreditation. It sets the conditions under which national accreditation bodies grant accreditation to third-party verifiers under the EN ISO/IEC 14065 standard, defines the control and oversight regime, and establishes mutual recognition between national accreditation bodies through peer evaluation by European Accreditation (EA). Verifiers cannot register in the CBAM Registry until September 1, 2026, when that module opens under the rules of IR 2024/3210 as amended by IR 2025/2550.

Caption: The 13 CBAM secondary acts group into 5 functional areas: transitional reporting, registry, authorization, calculation and verification, and certificate operations.

Adoption Pattern: Why 11 of 13 Acts Arrived in 2025

The Commission adopted only 2 of the 13 CBAM implementing regulations before 2025: IR 2023/1773 in August 2023 (needed immediately for transitional reporting) and IR 2024/3210 in December 2024 (needed for registry launch). The remaining 11 acts were adopted between March and December 2025, clustered in two bursts: March (authorization rules), October to November (offshore goods and verifier accreditation), and December (the full definitive-phase technical package).

This compression reflects the legislative sequence that Regulation (EU) 2023/956 created: the primary regulation delegated implementing power to the Commission, which then needed to develop detailed technical rules through the Standing Committee on Climate Change and the Union Climate Change Committee processes. The parallel passage of the Omnibus Regulation (EU) 2025/2083 in October 2025 required simultaneous amendment of IR 2025/486 and IR 2024/3210 before any of those definitives could enter force.

How CBAM Secondary Legislation Relates to the Primary Regulation

Which Articles of Regulation (EU) 2023/956 Each Secondary Act Implements

The 13 acts implement specific articles rather than the regulation as a whole. The key implementing-power grants are listed below.

• Article 3 and Article 7: calculation methodology (IR 2025/2547)
• Article 8: verification principles (IR 2025/2546) and verifier accreditation (DR 2025/2551)
• Article 10 and Article 14: registry infrastructure (IR 2024/3210, amended by IR 2025/2550)
• Article 17: authorized declarant authorization (IR 2025/486, amended by IR 2025/2549)
• Article 22: certificate price calculation (IR 2025/2548)
• Article 25: customs-registry data exchange (IR 2025/2619)
• Article 30a (ETS free allocation adjustment): SEFA methodology (IR 2025/2620)
• Article 7(7): default values (IR 2025/2621)
• Article 32 (transitional period): quarterly reporting (IR 2023/1773)
• Article 2(7) (EEZ/continental shelf): offshore goods (IR 2025/2210)

Does the CBAM Regulation Override the Implementing Regulations?

Regulation (EU) 2023/956 takes precedence over all implementing and delegated regulations. The secondary acts cannot extend, limit, or modify the obligations set in the primary regulation; they can only fill the procedural gaps that the primary regulation explicitly delegates. The Omnibus amendment (Regulation (EU) 2025/2083) amended the primary regulation directly, which then required corresponding amendments to IR 2025/486 and IR 2024/3210 via the December 2025 implementing acts.

CBAM Secondary Legislation and the Compliance Calendar

Understanding when each CBAM implementing regulation applies shapes the compliance calendar. The 4 critical dates governed by secondary legislation are listed below.

• December 31, 2024: IR 2024/3210 applies (registry open, authorization applications possible)
• March 31, 2025: IR 2025/486 applies (authorization application deadline infrastructure ready)
• January 1, 2026: IR 2025/2621 default values apply; DR 2025/2551 verifier rules apply
• September 1, 2026: verifier registration module opens (DR 2025/2551 via IR 2025/2550)

The first CBAM declaration, due September 30, 2027 and covering calendar year 2026 imports, requires compliant embedded emissions data calculated under IR 2025/2547 and verified under IR 2025/2546. Both acts have been in force since their publication in December 2025. Importers who began monitoring emissions using the transitional methodology under IR 2023/1773 need to confirm their data aligns with the updated calculation requirements in IR 2025/2547.

For the complete CBAM regulation framework, including the primary regulation text and the Omnibus amendment, see the dedicated regulation guide.

Frequently Asked Questions About CBAM Implementing Regulations

How many CBAM implementing regulations are there?

13 secondary acts implement Regulation (EU) 2023/956 as of April 2026. The full list runs from IR 2023/1773 (adopted August 17, 2023, governing transitional-period reporting) to IR 2025/2621 (adopted December 16, 2025, setting definitive-phase default values). One of the 13 is technically a delegated regulation (DR 2025/2551 on verifier accreditation) rather than an implementing regulation.

Is IR 2023/1773 still in force?

IR 2023/1773 remains on the books but its operational provisions apply only to the transitional period (October 1, 2023 to December 31, 2025). Its quarterly reporting schedules, alternative calculation methods, and €10–50 penalty rates do not apply to the definitive phase that began January 1, 2026. Importers still retain any historical data obligations from the transitional period under this regulation.

Does the CBAM Omnibus change any implementing regulations?

Yes. Regulation (EU) 2025/2083 (the Omnibus regulation) amended the primary regulation, which required corresponding updates to 2 implementing regulations. IR 2025/2549 amended IR 2025/486 to align authorized declarant procedures with the Omnibus changes. IR 2025/2550 amended IR 2024/3210 to update the registry for definitive-phase certificate operations.

What does IR 2025/2547 govern?

IR 2025/2547 is the calculation methodology regulation. It defines how operators and importers calculate the embedded emissions of CBAM goods, including monitoring plan requirements, the system boundaries for each production process, and the calculation equations specific to each of the 6 covered sectors (iron and steel, cement, aluminium, fertilizers, electricity, and hydrogen). This is the core technical reference for the embedded emissions figure that appears in CBAM declarations.

Do implementing regulations apply to non-EU exporters?

CBAM implementing regulations bind EU importers and EU competent authorities, not non-EU exporters directly. Non-EU exporters are affected because the calculation and verification methodologies (IR 2025/2547 and IR 2025/2546) determine the data format and quality that exporters must provide to EU importers. Exporters who supply verified emissions data compliant with IR 2025/2547 enable their EU importers to declare actual emissions rather than default values, which is financially beneficial as default value mark-ups increase to 20% in 2027 and 30% from 2028.

Are there additional CBAM implementing regulations expected?

As of April 2026, 2 pending legislative proposals exist: COM(2025)989, which proposes to expand CBAM scope to approximately 180 downstream steel- and aluminium-intensive products from January 2028, and COM(2025)990, which proposes a Temporary Decarbonization Fund for EU exporters. Both require co-legislator approval through ordinary legislative procedure. If adopted, each would likely trigger further implementing regulations covering their specific procedural requirements. The CBAM Omnibus article covers the most recent primary regulation amendments in detail.

Related CBAM Compliance Topics

What Is the Difference Between the CBAM Regulation and Implementing Regulations?

Regulation (EU) 2023/956 is the primary legislation adopted by the European Parliament and the Council under Article 192(1) TFEU. It establishes the CBAM mechanism, defines the 6 covered sectors, sets the certificate obligation, and creates the penalty structure. CBAM implementing regulations are Commission-level secondary acts that operate within the space the primary regulation opens.

The practical distinction for compliance teams: the primary regulation tells you that you need to surrender certificates equal to embedded emissions. The implementing regulations tell you exactly how to calculate those emissions (IR 2025/2547), how a verifier checks your calculation (IR 2025/2546), how the certificate price is set (IR 2025/2548), and how the registry processes your surrender (IR 2025/2550).

Are CBAM Implementing Regulations Subject to Change?

CBAM implementing regulations can be amended by the Commission acting alone, without requiring co-legislator approval, as long as the amendment stays within the delegated or implementing power granted by the primary regulation. This procedural flexibility means secondary acts can be updated more quickly than the primary regulation. The December 2025 package demonstrated this: 9 acts were adopted within a 6-day window (December 10 to 16, 2025) to meet the January 1, 2026 definitive-phase start.

Changes that exceed the delegated scope require primary regulation amendment through the full Parliament-Council procedure, as was the case with the Omnibus reform in 2025. The CBAM declaration process depends on the stability of the calculation and registry implementing acts in particular, since changes to those acts affect the format and content of annual declarations.

Are CBAM Certificates Governed by an Implementing Regulation?

CBAM certificates are created, held, surrendered, and cancelled in the CBAM Registry under the rules of IR 2024/3210 (as amended by IR 2025/2550). The certificate price is derived using the formula in IR 2025/2548. The volume of certificates an authorized declarant must hold quarterly is not set by an implementing regulation but directly by Article 22(2) of Regulation (EU) 2023/956 as amended by the Omnibus: at least 50% of cumulative embedded emissions since the start of the calendar year, assessed at each quarter end.