How are CBAM certificates calculated?

Embedded emissions equal the imported quantity times the emissions factor. That gross figure of certificates is then reduced by a credit for any carbon price already paid in the origin country, and scaled by the phase-in obligation factor, giving the net certificates to surrender.

How does carbon already paid abroad reduce my obligation?

Regulation (EU) 2023/956 lets importers deduct the carbon price effectively paid in the country of origin. The tool converts the foreign price paid into a certificate-equivalent number of tonnes at the EU ETS price, then subtracts it from the gross obligation.

What is the obligation phase-in factor?

During the definitive period from 2026 the CBAM obligation is introduced gradually as free EU ETS allocation is withdrawn. Setting the factor below 100% models that ramp; 100% represents the full obligation once free allocation has ended.

What are the quarterly holding rules?

Importers must hold CBAM certificates covering at least 80% of their cumulative emissions at the end of each quarter, with final surrender annually. The tool estimates the per-quarter quantity and the 80% minimum holding from your total.

Which goods are covered by CBAM?

The initial scope covers iron and steel, aluminium, cement, fertilisers, electricity, and hydrogen, with their precursors. Always confirm the CN codes of your specific products against the regulation, because coverage and default emissions values are product-specific.

What is the CBAM Certificate Quantity & Cost Planner?

Enter product quantity, embedded emissions factor, carbon price already paid in the origin country, and the EU ETS price to compute net CBAM certificates to surrender, estimated cost in euros, and quarterly holding requirements. For importers subject to CBAM from the 2026 definitive phase. It runs free in your browser on Gera Tools, with nothing uploaded.

CBAM Certificate Quantity & Cost Planner

Name: CBAM Certificate Quantity & Cost Planner
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

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CBAM puts a carbon price on imports of certain emissions-intensive goods so they face the same cost as EU-produced equivalents under the EU ETS. From the definitive phase in 2026, importers must buy and surrender certificates for their embedded emissions. This planner sizes that obligation and its cost from your own figures.

Which goods are in scope

The definitive CBAM scope covers goods in these sectors, identified by CN code:

Sector	Examples
Iron and steel	Hot-rolled coil, rebar, beams, tubes
Aluminium	Unwrought aluminium, profiles, foil
Cement	Clinker, Portland cement
Fertilisers	Ammonia, urea, nitric acid, ammonium nitrate
Electricity	Direct electricity imports
Hydrogen	Electrolytic and other hydrogen

Confirming your exact CN codes against Annex I of Regulation (EU) 2023/956 is the first step — coverage is product-specific and some subheadings are excluded.

How it works

The calculation starts from embedded emissions and nets off carbon already paid abroad before applying the phase-in:

embedded emissions = quantity × emissions factor
foreign credit     = (foreign price paid / EU ETS price) × embedded emissions
net certificates   = max(0, embedded − foreign credit) × obligation factor
estimated cost     = net certificates × EU ETS price

It also estimates the quarterly profile, since importers must hold certificates covering at least 80 percent of cumulative emissions at the end of each quarter, with final surrender once a year.

Worked example

Importing 1,000 tonnes of steel at an embedded factor of 1.9 tCO2e per tonne gives 1,900 tCO2e. With no carbon paid abroad, an EU ETS price of 80 euros, and a full obligation, that is 1,900 certificates costing about 152,000 euros — roughly 380 certificates to hold at each quarterly checkpoint.

Now assume the steel originates from a country with a domestic carbon price of 20 euros per tonne of CO2e already paid:

Foreign credit: (20 / 80) × 1,900 = 475 certificates offset
Net certificates: 1,900 − 475 = 1,425
Estimated cost: 1,425 × €80 = €114,000

The foreign credit reduces the obligation by 25% in this example, illustrating why the origin country’s carbon pricing regime directly affects CBAM cost — and why supplier carbon disclosure is becoming commercially important.

Practical guidance

Use verified installation data (actual embedded emissions from the manufacturer) where available; EU default emissions values apply only when actual data cannot be obtained and tend to be conservative. The phase-in obligation factor will increase as EU ETS free allocations are withdrawn over time, so budget models should plan for rising obligations year on year. Always confirm the current certificate price and your specific CN codes with your CBAM declarant or customs adviser before committing budget.