Illustrative calculation: if Northbridge Components Ltd exports 100 tonnes of steel components to the EU, and the verified embedded emissions are 1.8 tonnes of carbon dioxide equivalent per tonne, its reported emissions are 180 tonnes. At an assumed EU carbon price of €75 per tonne, the gross exposure is €13,500 before any deduction for a carbon price already paid in the country of production. That is the practical starting point for understanding the carbon border adjustment mechanism explained for exporters.
Northbridge is a fictional example, and the calculation uses disclosed assumptions rather than a live company claim. The actual figure depends on the commodity code, production route, reporting method, EU carbon price and any eligible carbon charge paid overseas.
“We sell into Europe, so surely the EU importer deals with CBAM?”
Usually, the EU importer carries the legal obligation. That doesn’t mean the exporter can ignore the regime. The importer needs information about the emissions embedded in the goods, and poor or missing data can affect customs clearance, supplier approval and future contract negotiations.
CBAM currently covers selected goods including cement, iron and steel, aluminium, fertilisers, electricity and hydrogen. The list is defined by EU customs commodity codes, not by a broad description such as “manufactured products”. A business exporting a finished article may therefore be outside scope, while another business shipping a relatively simple steel product may be inside it.
The transition period ran from October 2023 to December 2025, during which importers reported embedded emissions but did not surrender CBAM certificates. From 2026, the financial mechanism applies to goods within scope. The importer purchases certificates linked to the emissions attributed to the imported goods, subject to the regime’s rules on free allocation and carbon prices paid in the country of origin.
The caveat: don’t assume every shipment needs a full product life-cycle assessment. CBAM calculations focus on the emissions defined by the applicable methodology. A proportionate, product-level inventory is often more useful than an impressive but irrelevant corporate footprint.
“Which UK exports are actually caught?”
This is where a customs specialist and a carbon accountant need to work together. Start with the EU Combined Nomenclature commodity code for each exported product. Then check whether that code appears in the current CBAM regulation and whether the relevant threshold or exemption applies.
For example, a UK manufacturer exporting primary aluminium may face a different data requirement from a business exporting an assembled machine containing a small aluminium component. The material may be present in both products, but the customs treatment is not necessarily the same.
Keep three questions separate:
- Is the exported product covered by a CBAM commodity code?
- Who is the importer of record in the EU?
- Can the producer provide actual emissions data using the required calculation method?
The first question determines scope. The second determines who handles the formal EU filing. The third determines whether the importer has credible information or has to rely on default values, which may be commercially unattractive.
UK exporters should also avoid confusing CBAM with the UK Emissions Trading Scheme. The UK ETS guidance covers installations and aviation activities participating in the UK market; it does not replace the EU importer’s CBAM obligations.
The caveat: a commodity code review is not a carbon audit. It tells you whether the goods may be covered, not how much embedded carbon they contain or whether your factory data is defensible.
“Can we just send the importer our annual Scope 1 and Scope 2 total?”
Not reliably. CBAM is tied to the imported goods, their production process and the installation where they were made. An annual company footprint can provide useful source data, but it rarely answers the importer’s product-level questions on its own.
A workable evidence pack normally includes production volumes, fuel consumption, purchased electricity, process emissions, relevant precursor materials and the allocation method used to assign emissions to each product. You should retain invoices, meter readings, production records, calculation files and the emissions factors applied.
The GHG Protocol Corporate Standard is useful for understanding corporate Scope 1 and Scope 2 accounting, but CBAM reporting may require a more focused production calculation. Do not present a corporate inventory as CBAM-compliant without checking the specific methodology.
Direct and indirect emissions
Direct emissions usually come from fuel combustion and industrial processes at the installation. Indirect emissions generally relate to purchased electricity, although the treatment depends on the goods and the applicable EU rules.
Suppose a steel line uses 420,000 kilowatt-hours of electricity and the relevant factor is 0.20 kilograms of carbon dioxide equivalent per kilowatt-hour. That gives 84,000 kilograms, or 84 tonnes, of indirect emissions. If the line produces 2,000 tonnes of export product, the electricity intensity is 0.042 tonnes of carbon dioxide equivalent per tonne of product.
That number is more useful to an importer than a statement saying the whole company emitted 3,400 tonnes last year. It connects energy use to the goods crossing the border.
The caveat: more data isn’t automatically better data. If allocation rules are unclear, adding more spreadsheets can create false precision. Document the boundary and assumptions before chasing another decimal place.
If supplier or production data is incomplete, a targeted supplier engagement letter for Scope 3 data can help structure requests to upstream suppliers. That matters where precursor materials form a material part of the embedded emissions.
“The importer can use default values, so why should we spend money on this?”
Because default values may not reflect an efficient UK production process, and the commercial consequences sit beyond the certificate calculation. An importer comparing two suppliers may prefer the one that can provide specific, traceable emissions data.
Use default values as a fallback, not as your data strategy. The gross calculation is broadly:
Covered goods multiplied by embedded emissions intensity, multiplied by the relevant certificate price, less any permitted adjustment for a carbon price paid in the country of origin.
Return to Northbridge. Its 100 tonnes of steel components at 1.8 tonnes of carbon dioxide equivalent per tonne produce 180 tonnes of embedded emissions. At the assumed €75 price, the gross exposure is €13,500. If Northbridge can evidence an eligible carbon charge of €10 per tonne on those emissions, the illustrative adjustment could be €1,800, leaving €11,700 before other applicable rules.
This is not an invoice forecast. The EU carbon price changes, the treatment of free allocation is prescribed by the regime, and an overseas carbon payment must meet the relevant evidence requirements. It is a management calculation showing which inputs need validating.
For wider reporting, the ISO 14064 standard provides a recognised framework for quantifying and reporting greenhouse gas emissions. It does not, by itself, make a calculation acceptable for CBAM. Methodology, records and traceability still matter.
Need a second pair of eyes on the calculation? Talk to our carbon audit team about your export data before the issue becomes a customer escalation.
The caveat: reducing emissions can lower exposure over time, but it won’t fix a weak evidence trail this quarter. Measurement and reduction should run in parallel.
“What should our export team do first?”
Don’t begin by buying software. Begin with a product and customer map.
- List EU-bound products. Record commodity codes, quantities, destination countries, importer of record and production site.
- Screen the codes. Confirm which products fall within the current CBAM scope and record the source and date of the decision.
- Map production emissions. Identify fuels, process emissions, electricity, precursor materials and production volumes for each relevant installation.
- Test data quality. Mark each input as measured, invoiced, estimated or based on a default. Assign an owner and retention location.
- Agree the commercial process. Decide who sends emissions information, how often it is updated and what happens if the importer challenges it.
- Build a reduction plan. Prioritise process efficiency, renewable electricity, fuel switching and material changes that reduce emissions intensity without compromising product quality.
Companies with complex supply chains may also benefit from a formal supply chain emissions audit. Smaller exporters can usually start with a controlled spreadsheet, provided the calculations are versioned, reviewed and backed by source documents.
What should the evidence file contain?
At minimum, keep the commodity-code decision, installation boundary, production quantities, energy records, emissions factors, allocation method, precursor data, calculation version and management sign-off. Add a clear explanation where an estimate is unavoidable.
That file has two audiences. Your importer needs usable figures. Your finance or sustainability lead needs confidence that the numbers can be reproduced six months later.
The caveat: CBAM readiness isn’t a one-off certification exercise. Product mix, energy contracts, production routes and EU rules can all change. A quarterly review is often more practical than a large annual scramble.
“Is CBAM only a compliance cost?”
No. It can expose where an export product is losing margin, where a customer may switch supplier and where investment would reduce both emissions and border exposure.
That doesn’t make every decarbonisation project worthwhile. A £200,000 equipment upgrade should be tested against energy savings, product volumes, capital cost, maintenance, customer requirements and the likely carbon price. The strongest business case usually combines several of these factors rather than relying on CBAM alone.
Finance directors should ask for three scenarios: current production, a credible efficiency plan and a higher-carbon-price case. Sustainability teams should make sure each scenario uses the same product boundary. Export managers should identify which customers require data now, rather than waiting for a formal request.
The EU CSRD overview is relevant to some larger EU customers and groups, but CSRD and CBAM are separate regimes. A customer may ask for CBAM data because of imported goods even when your UK company is outside CSRD.
The caveat: not every customer request is legally mandatory. Some are procurement requirements, internal climate targets or preparation for future rules. Ask what decision the data will support, then provide information at the right level of assurance.
“Can we wait until an importer asks for the numbers?”
You can, but that is a poor negotiating position. The exporter that has a defensible figure, a clear methodology and a sensible improvement plan is easier for an EU buyer to retain than the exporter asking for an extension.
The carbon border adjustment mechanism explained for exporters is ultimately a commercial readiness issue. Confirm scope by commodity code, calculate emissions at product level, preserve evidence and agree responsibilities with the importer. Then use the results to test pricing and investment decisions.
One quiet contrarian point: the best CBAM project may reveal that one product line is not worth exporting under its current process. That is not a reporting failure. It is useful management information.
Arrange a practical export carbon review if you need to confirm scope, test your calculation or prepare an importer evidence pack.
Frequently asked questions
Does CBAM apply to all UK exports to the EU?
No. CBAM applies to specified goods identified through EU commodity codes, including selected cement, iron and steel, aluminium, fertiliser, electricity and hydrogen products. A finished product containing one of those materials is not automatically covered. Check the precise code, product description and current EU rules before making a commercial decision.
Who submits the CBAM report: the UK exporter or the EU importer?
The EU importer, or an authorised customs representative in the relevant circumstances, generally handles the formal CBAM declaration and certificate process. The UK exporter supplies production and emissions information. Contracts should state who owns data collection, deadlines, corrections and the cost of missing or revised information.
What if we don’t know our product’s embedded emissions?
The importer may have to use prescribed default values or another permitted method. That can be less favourable than providing actual, well-supported data. Start with production volumes, fuel, electricity, process emissions and precursor materials. Label estimates clearly and replace them with measured or supplier-backed figures as the system matures.
Is a corporate carbon footprint enough for CBAM?
Usually not. A corporate footprint describes the organisation, while CBAM attributes emissions to covered goods and production installations. Your existing Scope 1 and Scope 2 inventory is a useful starting point, but you may need product-level allocation, precursor data and evidence that matches the CBAM methodology.
Frequently asked questions
Does CBAM apply to all UK exports to the EU?
No. CBAM applies to specified goods identified through EU commodity codes, including selected cement, iron and steel, aluminium, fertiliser, electricity and hydrogen products. A finished product containing one of those materials is not automatically covered. Check the precise code, product description and current EU rules before making a commercial decision.
Who submits the CBAM report: the UK exporter or the EU importer?
The EU importer, or an authorised customs representative in the relevant circumstances, generally handles the formal CBAM declaration and certificate process. The UK exporter supplies production and emissions information. Contracts should state who owns data collection, deadlines, corrections and the cost of missing or revised information.
What if we don’t know our product’s embedded emissions?
The importer may have to use prescribed default values or another permitted method. That can be less favourable than providing actual, well-supported data. Start with production volumes, fuel, electricity, process emissions and precursor materials. Label estimates clearly and replace them with measured or supplier-backed figures as the system matures.
Is a corporate carbon footprint enough for CBAM?
Usually not. A corporate footprint describes the organisation, while CBAM attributes emissions to covered goods and production installations. Your existing Scope 1 and Scope 2 inventory is a useful starting point, but you may need product-level allocation, precursor data and evidence that matches the CBAM methodology.
