9) What Are the CBAM Deadlines and Key Dates?

Transitional Period Deadlines#

The transitional period runs from 1 October 2023 through 31 December 2025. During this period, importers submit quarterly CBAM reports with no financial obligations.

Quarterly reports are due one month after each quarter ends. Q4 2023 report was due 31 January 2024. Q1 2024 report was due 30 April 2024. Q2 2024 report was due 31 July 2024. Q3 2024 report was due 31 October 2024. Q4 2024 report was due 31 January 2025.

The final transitional reports cover activity through December 2025. Q4 2025 report is due 31 January 2026. This is the last report before the definitive period begins.

Reports are submitted through the CBAM Transitional Registry. Late submission can result in penalties from national competent authorities even though no financial obligations exist during the transitional period. Penalties vary by member state but typically start at hundreds of euros for late reports.

Definitive Period Start Date#

The definitive period begins 1 January 2026. From this date, importers must be authorised CBAM declarants and must purchase and surrender certificates to cover embedded emissions in goods imported.

Only authorised declarants can import CBAM goods from 1 January 2026. Applications for authorisation should be submitted well before this date. Processing times vary by member state but typically take several weeks. Late applications risk inability to import at year start.

Annual Declaration Deadlines#

Annual CBAM declarations are due by 30 September following each calendar year. This deadline was extended from 31 May under the October 2025 simplification regulation.

The first annual declaration covers calendar year 2026 and is due 30 September 2027. This declaration must include total quantities of CBAM goods imported during 2026, embedded emissions for those goods, calculations of certificate requirements, and surrender of certificates covering those emissions.

Subsequent declarations follow the same pattern. The 2027 declaration is due 30 September 2028. The 2028 declaration is due 30 September 2029.

The extended deadline recognises that obtaining verified emissions data from international suppliers takes time. Four months after year-end is more realistic than two months for complex supply chain data collection.

Certificate Purchase Deadlines#

Quarterly certificate purchase requirements apply during each calendar year. By the end of Q3 (30 September), importers must hold certificates covering at least 50% of their expected annual obligation. This was reduced from 80% under the October 2025 simplification regulation.

The 50% requirement is a minimum. Importers can purchase more certificates earlier if they wish to lock in prices or ensure adequate inventory. Certificates can be purchased at any time through the CBAM Registry at the prevailing weekly price.

By the declaration deadline (30 September following the year), importers must hold sufficient certificates to surrender covering their actual annual emissions. If actual emissions exceeded estimates and insufficient certificates were purchased, additional certificates must be purchased before surrender.

Certificate Surrender Deadline#

Certificates must be surrendered by 30 September when the annual declaration is submitted. Surrender is done through the CBAM Registry as part of the declaration process.

Failure to surrender sufficient certificates by the deadline results in penalties. Member states must impose penalties between €10-50 per tonne of unreported emissions plus potentially additional fines for non-compliance. Penalties vary by member state.

Free Allocation Phase-Out Timeline#

Free allocation under EU ETS for CBAM sectors phases out from 2026 to 2034. This directly affects CBAM obligations because certificate requirements increase as free allocations decrease.

• 2026: 97.5% free allocation remains, CBAM covers 2.5% of emissions
• 2027: 95.0% free allocation remains, CBAM covers 5.0% of emissions
• 2028: 90.0% free allocation remains, CBAM covers 10.0% of emissions
• 2029: 77.5% free allocation remains, CBAM covers 22.5% of emissions
• 2030: 51.5% free allocation remains, CBAM covers 48.5% of emissions
• 2031: 39.0% free allocation remains, CBAM covers 61.0% of emissions
• 2032: 26.5% free allocation remains, CBAM covers 73.5% of emissions
• 2033: 14.0% free allocation remains, CBAM covers 86.0% of emissions
• 2034: 0% free allocation remains, CBAM covers 100% of emissions

Certificate requirements increase each year even if embedded emissions and ETS prices remain constant. Companies must budget for escalating costs through 2034.

UK CBAM Timeline#

UK CBAM starts 1 January 2027 with full implementation and no transitional period. Registration with HMRC is required when annual imports exceed £50,000 value threshold.

Quarterly returns are due by the end of the second month following each quarter. Q1 2027 return is due 31 May 2027. Q2 2027 return is due 31 August 2027. Q3 2027 return is due 30 November 2027. Q4 2027 return is due 28 February 2028.

Payment is due with each quarterly return. This differs from the EU system where certificate purchase is separate from declaration timing.

Verification Deadlines#

From 2026, actual emissions data used in EU CBAM declarations must be verified by accredited third-party verifiers. Verification reports must be obtained before declaration submission.

Verification typically takes 4-8 weeks depending on installation complexity and verifier workload. Site visits, documentation review, and report preparation all require time.

To meet the 30 September declaration deadline, verification should begin by July at the latest. Earlier is better to avoid year-end verifier capacity constraints. Many installations will need verification, creating potential bottlenecks.

Operators should engage verifiers well before data is needed. Building verifier relationships and scheduling site visits months in advance ensures timely completion.

Review and Reporting Deadlines#

Article 30 of the CBAM Regulation requires the Commission to report to Parliament and Council on CBAM implementation and effectiveness by 31 December 2028. This report will assess whether CBAM is achieving its objectives and consider potential expansions.

Topics for the 2028 review include downstream products, organic chemicals, polymers, indirect emissions for currently excluded sectors, and methodology improvements. The review may lead to amendments expanding CBAM scope.

Companies should monitor the 2028 review outcomes. Expansions would create new obligations potentially affecting products not currently in scope.

What Missing Deadlines Means#

Late transitional reports trigger administrative penalties. These vary by member state but are typically hundreds to thousands of euros per late report.

Late authorisation applications risk inability to import from 1 January 2026. Importing without authorisation is prohibited and subject to penalties.

Insufficient certificates at declaration time trigger penalties of €10-50 per tonne unreported plus potential additional fines. For large importers, this can mean hundreds of thousands of euros in penalties.

Late declarations create administrative violations subject to member state penalties. Beyond financial penalties, late compliance creates audit risk and potential customs issues.

Deadlines are firm. National competent authorities have limited discretion to extend them. Companies must build processes ensuring timely data collection, calculation, verification, and submission.