The EU’s Carbon Border Adjustment Mechanism (CBAM), Explained
CBAM entered its definitive period on January 1, 2026. Here is what the EU carbon border tax covers, who must comply, and the new 50-tonne exemption.
The Carbon Border Adjustment Mechanism (CBAM) is an EU regulation that puts a carbon price on imports of specific carbon-intensive goods, mirroring the price EU producers already pay under the EU Emissions Trading System. Its definitive period began on January 1, 2026, following coordinated deployment across all EU member states, according to the European Commission’s Directorate-General for Taxation and Customs Union. In the mechanism’s first reporting window, January 1-6, 2026, importers declared 1.655 million tonnes of CBAM-covered goods, and more than 12,000 economic operators applied for the authorization now required to import them, with roughly 4,100 achieving authorized declarant status by January 7.
What CBAM covers
CBAM applies to five categories of imported goods: iron and steel, aluminium, fertilizers, cement, and electricity and hydrogen. Iron and steel account for the large majority of covered import volumes — 98% of initial volumes recorded — followed by fertilizers at 1.2%, cement at 0.5%, and aluminium at 0.3%, with electricity and hydrogen imports recording negligible volumes in initial reporting. The mechanism requires importers of these goods to purchase CBAM certificates corresponding to the greenhouse gas emissions embedded in what they import, priced to match the EU Emissions Trading System carbon price, so that imported goods face a comparable carbon cost to goods produced within the EU.
What importers must now do
Economic operators must submit a CBAM authorization application and hold “authorized declarant” status before importing covered goods. EU customs authorities validate each declaration in real time against the CBAM Registry before releasing goods into circulation, meaning the compliance check now happens at the point of import rather than after the fact.
The new exemption for small importers
Regulation (EU) 2025/2083, adopted October 8, 2025, published October 17, 2025, and in force from October 20, 2025, introduced a mass-based de minimis exemption ahead of the definitive period’s start. Importers bringing in fewer than 50 tonnes per year of covered iron, steel, aluminium, fertilizer, or cement goods are exempt from CBAM obligations; the exemption does not extend to electricity or hydrogen imports. Once an importer exceeds the 50-tonne threshold in a given calendar year, full compliance obligations apply retroactively to all of that year’s imports, not just the tonnes above the threshold. The European Commission designed the threshold so that roughly 99% of embedded emissions in covered imports remain within CBAM’s scope despite exempting the smallest importers by volume. The same regulation reduced the share of embedded emissions for which importers must surrender certificates each quarter, from 80% to 50%, and excluded non-calcined kaolinic clays from CBAM’s scope. The Commission retains authority to adjust the threshold as trade patterns evolve.
Why the exemption was introduced
The simplification followed the European Commission’s broader Omnibus package, launched in February 2025, which has also narrowed reporting requirements under the Corporate Sustainability Reporting Directive (CSRD), the Corporate Sustainability Due Diligence Directive (CSDDD), and the EU Taxonomy Regulation. Across each of these files, the stated rationale has been reducing administrative burden — particularly for smaller companies — while preserving the underlying policy’s core coverage, a trade-off reflected in CBAM’s case by exempting an estimated majority of importers by count while retaining coverage of about 99% of embedded emissions by volume.
Where CBAM fits among carbon pricing systems globally
The OECD tracks how CBAM’s underlying logic — pricing carbon to prevent “carbon leakage,” where production shifts to jurisdictions with weaker climate policy — compares with carbon pricing levels in other economies. The OECD’s Effective Carbon Rates 2025 report tracks carbon pricing developments across member and partner countries, providing the comparative baseline CBAM’s border adjustment is designed to reflect.
What remains unresolved
CBAM’s definitive period is less than a year old as of mid-2026, and full-year compliance data — including how many authorized declarants ultimately purchase and surrender CBAM certificates, and whether the 50-tonne threshold requires further recalibration — is not yet available. The mechanism’s transitional reporting-only phase ran from October 2023 through the end of 2025; the definitive period covered here is the first phase in which certificate purchase and surrender obligations are financially binding.
Sources: European Commission’s Directorate-General for Taxation and Customs Union, Regulation (EU) 2025/2083, Effective Carbon Rates 2025
Featured image: photo by Bilal Ahmed on Pexels (free Pexels license).
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I specialize in sustainability education, curriculum co-creation, and early-stage project strategy. At WINSS, I craft articles on sustainability, transformative AI, and related topics. When I’m not writing, you’ll find me chasing the perfect sushi roll, exploring cities around the globe, or unwinding with my dog Puffy — the world’s most loyal sidekick.
