An EU importer (declarant), an indirect customs representative, or a non-EU producer asks about the EU Carbon Border Adjustment Mechanism.
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This Guide is general tax/accounting reference material for AI-assisted workflows. It has not been reviewed for your personal facts, documents, elections, deadlines, residency, filing status, or local procedures. Do not rely on it to file, pay, amend, or take a tax position without review by a qualified professional in the relevant jurisdiction.
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Transitional period start date
1 October 2023Regulation (EU) 2023/956; Implementing Regulation (EU) 2023/1773
First quarterly CBAM report (Q3 2023) due date
31 January 2024Implementing Regulation (EU) 2023/1773
Quarterly CBAM report (Q4 2024) due date
31 January 2025Implementing Regulation (EU) 2023/1773
Definitive period start date
1 January 2026Regulation (EU) 2023/956
Final quarterly transitional report (Q4 2025) due date
31 January 2026Implementing Regulation (EU) 2023/1773
First annual CBAM declaration (for year 2026) due date
31 May 2027Regulation (EU) 2023/956
Annual CBAM declaration due date (recurring, definitive period)
31 May for the prior calendar yearRegulation (EU) 2023/956
Quarterly transitional report submission window
Within one month of quarter endImplementing Regulation (EU) 2023/1773
Transitional period end date
31 December 2025Implementing Regulation (EU) 2023/1773
Default values freely allowed — transitional period grace period end
Q3 2023 to end of Q3 2024 (any methodology including default values allowed)Implementing Regulation (EU) 2023/1773
Default value usage cap from Q4 2024 onwards (by weight per declarant per quarter)
≤ 20% of imported product weight per declarant per quarterImplementing Regulation (EU) 2023/1773 Article 4
ETS free allocation factor in 2026 (CBAM certificate surrender reflects only 2.5% of benchmark emissions)
97.5% free allocation retained in 2026 (importer surrenders certificates for 2.5% × benchmark emissions)Regulation (EU) 2023/956, Article 36 / Annex II
ETS free allocation phaseout completion year (reduces to 0%)
0% free allocation by 2034Regulation (EU) 2023/956, Article 36
CBAM certificate unit
1 certificate = 1 tCO₂eRegulation (EU) 2023/956
CBAM certificate price basis
Weekly average price of EU ETS auctionsRegulation (EU) 2023/956
Certificate sell-back limit per quarter
Up to 1/3 of certificates held at end of each quarter may be sold back at original priceRegulation (EU) 2023/956
Unsurrendered certificates cancellation deadline
Certificates not surrendered by 31 May of the year following the import year are cancelledRegulation (EU) 2023/956
Penalty for failure to file quarterly report (transitional period) — per tonne of unreported emissions
EUR 10 – EUR 50 per tonne of unreported emissionsImplementing Regulation (EU) 2023/1773, Article 16
Penalty for failure to surrender CBAM certificates (definitive period)
3 × the average price of certificates over preceding year × shortfall in tonnesRegulation (EU) 2023/956, Article 26
Original de minimis exemption threshold (by shipment value)
Shipments ≤ EUR 150 in value exemptRegulation (EU) 2023/956
Omnibus 2025 proposed de minimis threshold (by annual tonnage per importer)
50 tonnes per year per declarant (proposed, not yet enacted — confirm as-enacted text)Regulation (EU) 2023/956, Article 2(3); Omnibus simplification proposal (February 2025)
Embedded Emissions calculation formula
Embedded Emissions (tCO₂e) = Quantity (t) × Specific Embedded Emissions (tCO₂e / t)Regulation (EU) 2023/956; Implementing Regulation (EU) 2023/1773
CBAM certificates to surrender formula (definitive period)
Certificates to surrender = Embedded Emissions − Free Allocation Factor − Carbon Price AdjustmentRegulation (EU) 2023/956, Article 31 / Annex II
Accredited verifier standard for actual emissions data (definitive period)
Must be verified by an accredited verifier under Implementing Regulation (EU) 2018/2067Implementing Regulation (EU) 2018/2067
Default values — verification requirement
Default values do not require verification by an accredited verifierImplementing Regulation (EU) 2023/1773
Cement — CN codes in scope
2507 00 80, 2523 (clinker, cement, white cement, aluminous cement)Regulation (EU) 2023/956, Annex I
Iron and steel — CN chapters/headings in scope
CN chapter 72 (most subheadings) plus selected articles of 7301, 7302, 7303, 7304, 7305, 7306, 7307, 7308, 7311, 7318, 7326Regulation (EU) 2023/956, Annex I
Fertilisers — CN chapters/codes in scope
CN chapter 31 (nitrogen fertilisers, mixed fertilisers) plus 2808 00 00 (nitric acid)Regulation (EU) 2023/956, Annex I
Aluminium — CN chapters in scope
CN chapter 76 (unwrought, semi-fabricated, articles) and selected wrought productsRegulation (EU) 2023/956, Annex I
Electricity — CN code in scope
2716 00 00 (only cross-border supplies)Regulation (EU) 2023/956, Annex I
Hydrogen — CN code in scope
2804 10 00Regulation (EU) 2023/956, Annex I
Countries/territories exempt from CBAM
EEA states (Iceland, Liechtenstein, Norway), Switzerland, and certain territories with full EU ETS coverage (Northern Ireland for electricity, Büsingen, etc. — Annex III)Regulation (EU) 2023/956, Annex III
Sectors where indirect emissions are in scope
Cement, fertilisers, electricity, hydrogenRegulation (EU) 2023/956
Sectors where indirect emissions are out of scope (transitional + early definitive period)
Iron and steel, aluminiumRegulation (EU) 2023/956
Monitoring and Reporting Regulation standard for actual emissions methodology
EU methodology equivalent to Monitoring and Reporting Regulation (EU) 2018/2066Implementing Regulation (EU) 2018/2066
Carbon price adjustment currency conversion basis
EUR converted at exchange rate of payment dateRegulation (EU) 2023/956, Article 9
Anti-circumvention provision reference
Article 27 — applies to structuring imports to circumvent CBAM (e.g., processing in third country to change CN code)Regulation (EU) 2023/956, Article 27
UK CBAM effective date
1 January 2027UK Government announcement (separate from EU Regulation (EU) 2023/956)
This file is a content skill that loads on top of cross-border-workflow-base. It implements:
Tax year coverage. Current for calendar 2025 (transitional reporting) and the early definitive period 2026, reflecting the Omnibus simplification proposal of February 2025 which introduced a small-importer de minimis (50 tonnes/year per declarant) and clarified default-value usage.
The reviewer is the customer of this output. CBAM emissions data flows from production-site engineering records, customs classifications, and external verification. Every output must be reviewed by a credentialed practitioner (customs broker, EU import lawyer, or accredited verifier under Implementing Regulation (EU) 2018/2067) before submission.
This skill covers:
This skill does NOT cover:
eu-ets-allowances.md (forthcoming).Timeline table
| Date | Event |
|---|---|
| 1 October 2023 | Transitional period begins; first quarterly report due |
| 31 January 2024 | First quarterly report (Q4 2023) due |
| 31 January 2025 | Quarterly report (Q4 2024) due |
| 1 January 2026 | Definitive period begins; financial liability via certificates |
| 31 January 2026 | Final quarterly transitional report (Q4 2025) due |
| 31 May 2027 | First annual CBAM declaration (for 2026) due, with certificate surrender |
| Phased ETS free allocation phaseout | 2026: 97.5% free → reduces to 0% by 2034 (annual schedule in Article 36) |
Penalty exposure table
| Trigger | Penalty |
|---|---|
| Failure to file quarterly report (transitional period) | EUR 10 – EUR 50 per tonne of unreported emissions (Implementing Regulation (EU) 2023/1773 Article 16) |
| Failure to surrender certificates (definitive period) | 3 × the average price of certificates over preceding year × shortfall in tonnes (Article 26) |
| Unauthorised import in definitive period | Goods may be denied release; declarant penalties per Member State implementation |
The UK announced a domestic CBAM effective 1 January 2027 covering aluminium, cement, ceramics, fertilisers, glass, hydrogen, iron and steel (not electricity). Scope and methodology align broadly with EU CBAM. Goods that pass through the UK before importation to the EU may face double pricing in some scenarios — review preference treatment and customs sequencing.
The reviewer brief must include:
Before delivering output, verify:
This skill and its outputs are provided for informational and computational purposes only and do not constitute tax, legal, or financial advice. CBAM scope, methodology, and pricing are evolving rapidly with Commission delegated acts and the 2025 Omnibus simplification. Every output must be reviewed and signed off by a credentialed customs / CBAM specialist before submission of a quarterly report or annual declaration.
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