The EU CBAM timeline spans 11 years, from October 1, 2023 (when the first reporting obligations activated) to January 1, 2034 (when free EU ETS allocations for CBAM sectors reach zero). Understanding this timeline is mandatory for every importer of iron and steel, cement, aluminium, fertilizers, electricity, and hydrogen into the EU customs territory. The EU CBAM guide covers the full mechanism; this page covers every date, every deadline, and the regulation article behind each one.
What Is the CBAM Implementation Timeline?
The CBAM implementation timeline is the sequence of legally binding deadlines under Regulation (EU) 2023/956, as amended by Regulation (EU) 2025/2083, governing how the EU Carbon Border Adjustment Mechanism phases in from a reporting-only transitional period through to full financial operation by 2034. The timeline spans two major phases: the transitional period (October 1, 2023 to December 31, 2025), during which importers reported emissions with no financial obligation, and the definitive phase (January 1, 2026 onward), in which authorized declarants purchase and surrender CBAM certificates priced at the EU ETS carbon price.
The critical 2025 Omnibus amendment (Regulation (EU) 2025/2083) shifted the most consequential deadlines, including extending the first CBAM declaration deadline from May 31, 2027 to September 30, 2027, and delaying certificate sales from an earlier projected date to February 1, 2027.
Complete CBAM Timeline: Every Key Date and Deadline
The 14 binding CBAM deadlines below span every major milestone in the EU CBAM timeline, from the transitional start through full phase-in. Each row includes the regulation article that creates the obligation.
| Date | Milestone | Regulation Reference |
|---|---|---|
| October 1, 2023 | Transitional period begins; quarterly reporting obligations activate | Article 32, Reg. (EU) 2023/956 |
| January 31, 2024 | First quarterly CBAM report due (covering Q4 2023) | IR (EU) 2023/1773 |
| January 1, 2025 | Only EU calculation methodology accepted; equivalent third-country methods expire | IR (EU) 2023/1773 |
| December 31, 2025 | Transitional period ends; last quarterly report covers Q3 2025 | Article 32, Reg. (EU) 2023/956 |
| January 1, 2026 | Definitive phase begins; financial obligations activate; all 6 sectors simultaneously | Article 36(2), Reg. (EU) 2023/956 |
| March 31, 2026 | Deadline for provisional authorization applications | Article 17(7a), Reg. (EU) 2025/2083 |
| September 1, 2026 | Verifier registration opens in CBAM Registry | DR (EU) 2025/2551; Reg. (EU) 2025/2083 |
| February 1, 2027 | Certificate sales begin via Common Central Platform | Regulation (EU) 2025/2083 |
| September 30, 2027 | First CBAM declaration due; covers calendar year 2026 imports | Article 6, as amended by Reg. (EU) 2025/2083 |
| October 31, 2027 | Deadline to request buyback of excess 2026 certificates (up to 50%) | Article 23, as amended by Reg. (EU) 2025/2083 |
| November 1, 2027 | Cancellation of unreturned 2026 certificates | Article 24(1), as amended |
| September 30 (annual) | Ongoing annual CBAM declaration deadline for each preceding year | Article 6, Reg. (EU) 2023/956 |
| January 1, 2028 | Proposed: ~180 downstream steel- and aluminium-intensive products added to scope (pending co-legislator approval of COM(2025)989) | COM(2025)989 |
| January 1, 2034 | Free EU ETS allocation for CBAM sectors reaches 0%; full financial phase-in complete | Article 10a(1a), Directive 2003/87/EC as amended |
Caption: The EU CBAM timeline from the October 2023 transitional start through to the 2034 full phase-in of certificate obligations.
The Transitional Period: October 2023 to December 2025
The CBAM transitional period ran from October 1, 2023 to December 31, 2025 and carried zero financial obligation. Importers of the 6 Annex I sectors submitted quarterly reports disclosing the quantity, origin, and embedded emissions of their CBAM goods, but purchased no certificates and paid no charges. The legal basis is Article 32 of Regulation (EU) 2023/956, with the detailed reporting mechanics set out in Implementing Regulation (EU) 2023/1773.
Three calculation methods were accepted during the transitional period: the EU full calculation methodology using actual production data, a default value approach based on IEA country-specific data, and an alternative methodology allowing equivalent third-country measurement systems. The alternative methodology expired on January 1, 2025 under IR 2023/1773, leaving only the EU calculation method and defaults accepted for Q1–Q3 2025 reports.
The transitional period served as a data-gathering and system-readiness phase. Over 12,000 authorization applications were submitted before the definitive phase launched, and over 4,100 operators received authorization by January 7, 2026. Non-reporting during the transitional period carried penalties of €10–50 per tonne CO₂e unreported under Article 35 of IR 2023/1773, significantly below the definitive phase penalty of €100 per tonne CO₂e.
The Definitive Phase: January 2026 Onward
The definitive CBAM phase began on January 1, 2026, activating the full financial obligation for importers of all 6 Annex I sectors simultaneously. From this date, only importers holding authorized declarant status under IR (EU) 2025/486 may legally import CBAM goods into the EU. Unauthorized importers face penalties of €300–500 per tonne CO₂e, representing 3 to 5 times the standard rate.
The CBAM deadline most important for 2026 importers falls on March 31, 2026: this is the last date to submit a provisional authorization application while continuing to import. Importers who applied by March 31, 2026 may continue importing pending their competent authority's decision, which can take up to 120 days from a complete application under Article 4(1) of IR 2025/486.
Certificate pricing in 2026 uses a quarterly average of EU ETS auction clearing prices under Article 22(1a), inserted by Regulation (EU) 2025/2083. From 2027, pricing shifts to a weekly average under Article 22(1). The EU ETS price stood at approximately €70 per tonne CO₂e in late March 2026 (Q1 2026 range: €66–90), though this figure fluctuates daily with market conditions.
The net financial obligation in 2026 is significantly reduced by the EU ETS free allocation factor. Because 97.5% of free ETS allocation for CBAM sectors remains in 2026 (CBAM factor: 2.5%), the effective certificate obligation is only 2.5% of gross embedded emissions. A blast furnace steel importer paying €70 per tonne CO₂, with an emission factor of approximately 2.0 tonnes CO₂ per tonne of steel, faces a gross CBAM cost of €140 per tonne but a net 2026 obligation of approximately €3.50 per tonne, because of this allocation offset.
The free allocation adjustment follows the SEFA methodology established in IR (EU) 2025/2620. The CBAM regulation article covers the legal architecture behind each of these obligations.
The Free Allocation Phase-Out: 2026 to 2034
The free allocation phase-out schedule is the mechanism that makes the CBAM timeline financially significant for the long term. As free ETS allocations reduce, CBAM certificate obligations increase proportionally, making the 2029–2034 period the window where costs become material for most importers.
The 9-year phase-out schedule below, established under Article 10a(1a) of EU ETS Directive 2003/87/EC as amended, shows the CBAM factor (the percentage of embedded emissions that must be covered by CBAM certificates) and the free allocation remaining in each year.
| Year | CBAM Factor | Free Allocation Remaining | Net Cost (BF-BOF Steel @ €70/tCO₂) |
|---|---|---|---|
| 2026 | 2.5% | 97.5% | ~€3.50/tonne |
| 2027 | 5% | 95% | ~€7.00/tonne |
| 2028 | 10% | 90% | ~€14.00/tonne |
| 2029 | 22.5% | 77.5% | ~€31.50/tonne |
| 2030 | 48.5% | 51.5% | ~€67.90/tonne |
| 2031 | 61% | 39% | ~€85.40/tonne |
| 2032 | 73.5% | 26.5% | ~€102.90/tonne |
| 2033 | 86% | 14% | ~€120.40/tonne |
| 2034 | 100% | 0% | ~€140.00/tonne |
The steepest acceleration in this CBAM timeline occurs between 2029 and 2030, when the CBAM factor jumps from 22.5% to 48.5%. Importers planning supply chain decarbonization or supplier switching decisions need to model their exposure across this 2029–2030 cliff, not just their 2026 starting position.
What Changed After the Omnibus Amendment?
The October 2025 Omnibus amendment (Regulation (EU) 2025/2083, adopted October 8, 2025, in force October 17, 2025) revised the CBAM timeline in 5 material respects. The CBAM omnibus article details all changes; the timeline-specific changes are listed below.
The 5 timeline changes introduced by Regulation (EU) 2025/2083 are as follows.
- Declaration deadline extended: from May 31 to September 30 of the year following the import year (Article 6, as amended). The first declaration covering 2026 imports is due September 30, 2027, not May 31, 2027.
- Certificate sales start delayed: from an earlier projected date to February 1, 2027, via a Common Central Platform operated by the European Commission.
- Quarterly holding requirement reduced: from 80% to 50% of cumulative embedded emissions per quarter (Article 22(2), as amended), easing cash flow pressure in 2026.
- Verifier registration date fixed: September 1, 2026 as the earliest date verifiers can register in the CBAM Registry under DR (EU) 2025/2551.
- De minimis threshold introduced: importers with fewer than 50 annual tonnes of CBAM goods (per importer, across all product types, excluding electricity and hydrogen) are exempt from all CBAM obligations under Article 2(3a), inserted by Regulation (EU) 2025/2083.
Certificate Deadlines: Surrender, Buyback, and Cancellation
Three annual CBAM certificate deadlines operate after the first declaration year, each falling in a defined window. The CBAM declaration page covers the full submission process; the calendar below shows the three certificate lifecycle deadlines.
The 3 certificate deadlines that follow each declaration year are structured as follows.
- September 30: The annual CBAM declaration deadline. Authorized declarants submit their declaration and surrender certificates equal to the verified embedded emissions of goods imported in the preceding calendar year.
- October 31: The buyback deadline. Declarants may resell up to 50% of certificates purchased in that declaration year back to the competent authority at the original purchase price, covering over-purchased positions.
- November 1: Certificate cancellation date. CBAM certificates from the year before the prior year that were not surrendered or bought back are cancelled without compensation.
The first cycle of these 3 deadlines activates in autumn 2027: declaration due September 30, buyback deadline October 31, cancellation November 1. For 2026, CBAM certificates purchased via the Common Central Platform from February 1, 2027 onward are the instruments used for that surrender. The CBAM certificates page covers the certificate purchase mechanics ahead of that February 1, 2027 sales date.
CBAM Timeline: Contextual Border with Key Compliance Actions
The CBAM implementation timeline contains 4 compliance actions that require preparation well before their stated deadlines. Understanding these lead times is the operational difference between compliance and penalty exposure.
The 4 preparation-critical CBAM deadlines with their required lead times are listed below.
- March 31, 2026 authorization deadline: Requires a complete application (customs compliance history, tax registration, company documents) submitted to the national competent authority. The 120-day decision window under Article 4(1) of IR 2025/486 means applications must be complete, not just submitted.
- September 1, 2026 verifier registration: Verifiers must be accredited by a national accreditation body under EN ISO/IEC 14065 before they can register. The accreditation process itself requires months. Importers reliant on third-party verification of 2026 embedded emissions need to contract verifiers before the registry opens.
- February 1, 2027 certificate sales start: Importers need CBAM Registry accounts active, authorized declarant status confirmed, and a forecast of their 2026 embedded emissions calculated before this date to begin purchasing certificates. The CBAM authorized declarant page covers the authorization requirements ahead of this window.
- September 30, 2027 first declaration: The declaration requires verified embedded emissions data for every CBAM good imported during calendar year 2026, matched to CBAM certificates of equal quantity. Third-party verification under IR (EU) 2025/2546 requires a mandatory physical site visit for the first verification period.
Caption: The annual CBAM certificate lifecycle: declaration, buyback, and cancellation deadlines that recur each year from 2027 onward.
Is the CBAM Scope Expanding After 2026?
Yes. The European Commission published a formal legislative proposal (COM(2025)989) on December 17, 2025, proposing to expand the CBAM scope to approximately 180 downstream steel- and aluminium-intensive products from January 1, 2028. These downstream products include vehicle parts, machinery components, industrial radiators, and washing machines. This expansion requires approval by both the European Parliament and the Council under the ordinary legislative procedure, and is pending as of April 2026. The current CBAM scope (6 sectors) remains unchanged until co-legislators adopt the expansion.
Does the CBAM Timeline Apply to All Third Countries?
No. Goods from Iceland, Norway, Liechtenstein, and Switzerland are exempt from CBAM obligations under Article 2 and Annex III of Regulation (EU) 2023/956, because these countries either participate in the EU ETS or maintain electricity market integration with equivalent carbon pricing. The CBAM timeline applies to imports from all other third countries, including countries with their own carbon pricing schemes, though those importers can claim a deduction under Article 9 for carbon prices effectively paid in the country of origin.
When Does the Quarterly Holding Requirement Apply?
The quarterly holding requirement applies from the start of the definitive phase on January 1, 2026. Under Article 22(2) as amended by Regulation (EU) 2025/2083, authorized declarants must hold CBAM certificates equal to at least 50% of the cumulative embedded emissions of their imports since the start of each calendar year, assessed at the end of each quarter (March 31, June 30, September 30, December 31). Non-compliance with the quarterly holding requirement triggers a penalty of €100 per tonne CO₂e under Article 26(1), the same rate as failure to surrender certificates at the annual declaration deadline.
Does the CBAM Timeline Align with the UK CBAM?
No. The UK CBAM starts January 1, 2027, one year after the EU CBAM definitive phase, and uses a tax-based mechanism rather than a certificate system. The UK mechanism has different sector coverage, different price calculation methods, and different declaration deadlines. Goods traded across the UK-EU corridor may face compliance obligations under both mechanisms, and the risk of double-payment for UK-EU trade has not been formally resolved as of April 2026.