CBAM real-cost report: what the EU carbon border tariff actually costs

The EU Carbon Border Adjustment Mechanism (CBAM) entered its definitive phase on 1 January 2026. The transitional period, which ran from October 2023 through December 2025, required quarterly reporting of embedded emissions but no payment. From 2026 onward, importers in the six covered sectors must surrender CBAM certificates representing the embedded emissions of every shipment.

This post breaks down what CBAM costs in practice — by sector, by origin country, with worked examples.

What CBAM covers

CBAM applies to imports of these six product categories into the EU.

Iron and steel (HS 72, 73), aluminium (HS 76), cement (HS 25.23), fertilisers (HS 28, 31), electricity (HS 27.16), and hydrogen (HS 28.04.10).

These six were chosen because they represent the highest-emission sectors most exposed to "carbon leakage" — the risk that emissions-intensive production migrates outside the EU to avoid the EU Emissions Trading System (ETS) carbon price. The Commission has signaled CBAM will expand to cover downstream products and additional sectors over the second half of the decade, but as of 2026 the scope is limited to these six.

How the cost is calculated

The CBAM charge for a single shipment is: (embedded emissions in tonnes CO2e) × (EU ETS weekly average price in EUR per tonne) − (carbon price already paid in country of origin, if any) − (free allocation factor for EU producers, declining to 0 by 2034).

In 2026 the free allocation phase-out is in its first step. The phase-out accelerates each year — small in 2026, significant by 2030, full by 2034.

Embedded emissions — how they are measured

For each shipment, embedded emissions must be reported using either default emission values published by the Commission (per HS sub-heading and country, applied when actual data is not available) or verified actual emissions from the producer, audited by an accredited verifier.

Default values are deliberately conservative — generally higher than typical actual emissions — to incentivise producers to provide audited data. For steel (the largest CBAM category by import value), default values currently sit around 2.0–2.5 tonnes CO2e per tonne of crude steel for blast furnace production, dropping to 0.5–1.0 for electric arc furnace using scrap.

Steel — sector cost picture

Imports of HS 7208 (hot-rolled flat steel) from Türkiye and India will see CBAM costs of roughly 2.2 tonnes CO2e per tonne × ~€75 per tonne ETS price × 2.5% importer share = approximately €4 per tonne in 2026.

For a 10,000-tonne shipment, the 2026 cost is around €40,000 — a meaningful but absorbable line item. The same shipment at full phase-in (2034) is approximately €1.65M — fundamentally cost-shaping.

Aluminium — the highest-emission sector

Aluminium has the highest emissions intensity of the covered sectors. Default value: 8.6 tonnes CO2e per tonne (primary aluminium). 2026 cost: ~€16 per tonne. Full phase-in: ~€645 per tonne.

Producers in countries with grid electricity that is largely renewable (Norway, Iceland) face dramatically lower default values. The aluminium origin mix into the EU is shifting accordingly.

Cement, fertilisers, electricity, hydrogen

Cement is heavy and rarely transported long distances, so CBAM applies mostly to imports from Türkiye, the UK, Egypt, and the Western Balkans. Default value 0.8–1.0 tonnes CO2e per tonne of clinker. Full phase-in cost: ~€80 per tonne against an FOB price of €70–110 per tonne. Margins are thin and CBAM is the highest as a percentage of value among the six.

Fertilisers carry default emissions reflecting natural-gas-based production. Urea: ~1.8 tonnes CO2e per tonne; full phase-in cost ~€135 per tonne.

Electricity cross-border imports face CBAM based on the carbon intensity of the exporting grid. Verified low-carbon mixes pay minimal CBAM; coal-heavy generation pays significantly.

Hydrogen treats grey hydrogen at high default emissions, blue with verified CCS lower, and green hydrogen from renewable electricity essentially zero-rated.

How origin choice affects the cost

CBAM is, in effect, an origin-aware tariff layer. Two suppliers offering identical product specifications can land at different effective costs.

A supplier in Sweden — already inside ETS, no CBAM. A supplier in Türkiye — CBAM-applicable, mid-range default emissions. A supplier in Russia — CBAM-applicable, no carbon price domestically (no offset). A supplier in the UK — CBAM-applicable until UK launches its own CBAM (planned 2027), then cross-recognition possible.

Note: the EU and UK have signalled mutual CBAM recognition once the UK's own CBAM is operational. Imports from each into the other should then pass through without CBAM charge — preserving the historical EU-UK trade relationship despite both jurisdictions running carbon border adjustments.

What importers must do operationally

From January 2026, importers of CBAM-covered goods must:

1. Register as authorised CBAM declarants with the competent authority of their EU member state. Without this status, customs will not release CBAM-covered goods.

2. Submit annual CBAM declarations for all imports in the prior calendar year, by 31 May.

3. Surrender CBAM certificates equal to the embedded emissions of imported goods (less any free-allocation factor and less verified origin carbon prices paid).

4. Maintain documentation for at least four years: emissions calculations, verifier reports, country-of-origin proof, transactional records.

CBAM certificates are purchased from the competent authority at the weekly average ETS price. They cannot be traded between declarants.

Warning: the EU Commission has emphasised that carousel and shell-company workarounds will be policed actively. Sub-€1,000 consignments are exempt, but splitting shipments to fall below the threshold is explicitly prohibited and triggers penalties.

Worked example — steel reinforcing bar from Türkiye

A UK importer brings 5,000 tonnes of HS 7214.20 (steel reinforcing bar) from Türkiye into Italy. Embedded emissions at default value: 2.1 tonnes CO2e/tonne × 5,000 = 10,500 tonnes CO2e. ETS weekly average price (assumed): €75 per tonne. Gross CBAM charge: €787,500.

2026 importer share is 2.5%, so the 2026 CBAM cost is approximately €19,687. The same shipment in 2030 would cost €381,937; at full phase-in (2034), €787,500. On a roughly €3.5M FOB shipment, 2026 CBAM is 0.6%. By 2034 it is over 22%. CBAM is a slow-rising structural cost, not an immediate one.

Strategic implications

Three practical takeaways for importers.

1. Get verified actual emissions data from suppliers. Default values are punitive. The 6–18 months it takes to establish verified emissions reporting pays back as soon as the importer share rises above ~10%.

2. Build CBAM into supplier qualification. Carbon performance is now a sourcing variable for these six categories.

3. Treat 2026 as a calibration year. Process gaps surface this year. By 2028 the financial stakes climb meaningfully.