How to Calculate CBAM Cost: Step by Step

Step 1 — Identify the product and CN code

Scope and the applicable data follow the product’s CN (Combined Nomenclature) classification: a wrong CN code leads to the wrong default value, the wrong production route and therefore the wrong calculation. The first task is pinning down the correct CN code and whether the product is covered.

Step 2 — Determine the embedded emissions value

The input can come from two routes: (A) the applicable official default value published by the Commission — depending on CN code, country of origin and, for many goods, the production route; or (B) actual embedded emissions calculated under the applicable CBAM methodology for an installation that meets the conditions. The two are not automatically interchangeable — their requirements differ.

Actual emissions can produce lower, similar or higher exposure than the default value — they are not an automatic saving. You can compare the two with your own value in our decision guide:

Step 3 — Apply the default-value mark-up (where applicable)

Under the definitive-regime rules, declaring with a default value may require a regulatory mark-up on top, varying by year. The rates in the current dataset (read from the calculator’s dataset, not hand-typed): 2026 10%, 2027 20%, 2028 30%; 1% for fertiliser goods. Source: Implementing Regulation (EU) 2025/2621 (corrected by (EU) 2026/1740).

A short example (Türkiye, 7208, 2026): base default value 2.428 tCO₂e/t → value used after the 10% mark-up: 2.671 tCO₂e/t. No mark-up applies when verified actual data is used.

Step 4 — Apply the free allocation adjustment

EU producers under the EU ETS still receive free allocation for part of their emissions; to keep treatment equal, CBAM deducts a corresponding adjustment from the declared embedded emissions. The free allocation adjustment (CBAM benchmark) is the product group’s benchmark multiplied by the CBAM factor and the CSCF, and it determines the emissions for which certificates are ultimately required. As free allocation is phased out from 2026 to 2034, the adjustment shrinks — the CBAM cost of the same emissions rises year by year.

Careful: the CBAM factor (97.5% for 2026) is not “the percentage of CBAM payable” — it is the multiplier that scales the deduction. Basis: Regulation (EU) 2023/956; Implementing Regulation (EU) 2025/2620 (Annex, Equation 6); Commission Guidance No. 4.

Step 5 — Determine the emissions subject to the certificate obligation

The applicable free allocation adjustment is deducted from the embedded emissions value used; what remains is the "emissions subject to CBAM certificate obligation". If the result falls below zero, our engine — in line with the rules — floors it at 0: no estimated certificate cost arises in that case.

Step 6 — Apply the certificate price

The emissions subject to the certificate obligation are multiplied by the current CBAM certificate price. The price our calculator uses: Q2 2026: €75.28/tCO₂e — the Commission’s official quarterly price (weekly publication starts in 2027). Future prices move with the EU ETS; today’s price is no guarantee of tomorrow’s.

Step 7 — Multiply by quantity

The CBAM cost per tonne is multiplied by the annual imported quantity (tonnes); the result is the estimated total annual CBAM exposure. The calculation runs on tonnes — the dataset’s unit is tCO₂e per tonne of product, so avoid false precision with other units.

What this calculation does NOT include

The most important section for trust: the items our engine does not currently cover (listed after inspecting the engine code):

• Origin-country carbon price reduction: This calculation does not include any potential reduction that may be claimed for a carbon price effectively paid in the country of origin. Basis: Regulation (EU) 2023/956, Article 9.
• This estimate does not apply the 50-tonne single mass-based threshold assessed per importer and calendar year. Under the current rules, the threshold applies cumulatively to relevant goods in the iron and steel, aluminium, cement and fertiliser sectors; electricity and hydrogen are not covered by this 50-tonne exemption. Basis: Regulation (EU) 2023/956 as amended by Regulation (EU) 2025/2083.
• Declarant-specific legal exemptions and import/declaration handling costs are not represented in the calculation.
• The CSCF (cross-sectoral correction factor) for 2026–2030 has not yet been published, so 1.00 is assumed; this will be updated on publication.

If you take the actual-data route: the CBAM verification process — what does a verifier check?

Full worked example: Türkiye, CN 7208, 1,000 tonnes, 2026

Every value comes at build time from the shared calculation engine also used by the cost calculator, the steel guide and the comparison page — nothing typed by hand.

Illustrative calculation — not an official CBAM declaration. Dataset: IR (EU) 2025/2621 + IR (EU) 2026/1740.

Default value or actual emissions?

A default value is a quick starting point, but it carries a mark-up that rises by year and may not reflect your installation’s real performance. Actual emissions are installation-specific; but they come with methodology, documentation and, where applicable, verification requirements — and the result can also come out higher than the default.

The decision should weigh the difference between the two scenarios against the effort of preparing the data. We have a dedicated page where you can run that comparison with your own values:

Common calculation mistakes

• Using the wrong CN code — scope, value and route all follow it.
• Picking the wrong country/default value — values differ markedly by country for the same code.
• Ignoring the production route — both the default value and the benchmark can change between routes for the same CN code. See the aluminium guide for how the K/L routes work.
• Forgetting the default-value mark-up — 10% in 2026, higher in later years.
• Treating the CBAM factor as a directly payable percentage — it scales the deduction.
• Skipping the free allocation adjustment entirely — this overstates the cost.
• Inserting an EPD/PCF GWP result directly as CBAM embedded emissions.
• Assuming actual emissions always reduce the cost.
• Calculating with an outdated certificate price.
• Forgetting that the Article 9 carbon-price reduction is separate from this estimate.

EPD, LCA or PCF results should not automatically be inserted into a CBAM cost calculation as actual embedded emissions — the system boundary and methodology differ. The full explanation is in the decision guide. The full EPD/LCA vs CBAM distinction →

Frequently asked

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