CBAM for Suppliers: What Your EU Customer Needs From You

A customer has mentioned CBAM and asked you for carbon data, and you're wondering whether you've just been handed a major new compliance burden. Short answer for most suppliers: the CBAM obligation isn't yours — it sits with the EU importer. Your job is usually to give your customer the emissions data they need. Here's how CBAM works as of 2026, whether it touches you, and exactly what to provide.

This guide reflects the position as of mid-2026. Some implementing rules for the definitive regime are still being finalised — the European Commission's CBAM page has the current detail, and your customer's request will tell you what they actually need.

What CBAM is

The Carbon Border Adjustment Mechanism (CBAM) is an EU measure that puts a carbon price on certain imports into the EU, to match the price EU producers pay under the EU Emissions Trading System. It covers carbon-intensive goods: iron and steel, aluminium, cement, fertilisers, hydrogen, and electricity, plus certain downstream products of these.

The transitional reporting phase (October 2023 to December 2025) is over. CBAM's definitive period started on 1 January 2026. In the definitive regime, EU importers of CBAM goods must be authorised CBAM declarants and declare the embedded emissions of what they import each year — and, from 2027, pay for those emissions by buying and surrendering CBAM certificates.

The 2026 timeline, briefly

Two dates matter for understanding where things stand:

• 1 January 2026 — the definitive period began. Importers above the threshold need to register as authorised declarants and prepare to declare embedded emissions. 2026 is about registration and reporting, not yet payment.
• 1 February 2027 — certificate sales start (postponed from January 2026). From then, importers buy certificates to cover the embedded emissions of their imports, at a price linked to the EU ETS.

So in 2026, your customer's ask is a data and registration exercise. The money follows in 2027 — which is exactly why they're trying to get their emissions numbers right now.

The key point: whose obligation is it?

This is what most suppliers get wrong. The CBAM obligation falls on the EU importer of record — the company bringing the goods into the EU — not on the non-EU producer or supplier. If you are:

• A non-EU supplier selling CBAM goods to an EU customer: you have no direct CBAM filing obligation. But your EU customer needs your emissions data to complete their declaration — so they'll ask you for it.
• An EU supplier who isn't importing: CBAM doesn't apply to your domestic sales. It only bites on imports across the EU border.
• An EU importer yourself (you bring CBAM goods in from outside the EU): then the obligation is yours — see below.

So for the large majority of suppliers, CBAM shows up as a data request from a customer, not a filing you owe the authorities. This is the same pattern as other EU supply-chain rules like the EUDR or the German LkSG: the legal duty sits with the EU company, and it reaches you as their supplier through questions.

The de minimis threshold: many buyers are exempt

Under the simplifications adopted in 2025, there's a de minimis exemption: importers bringing in 50 tonnes or less of CBAM goods (cumulative net mass) per year are exempt from CBAM obligations entirely — no declaration, no certificates. Hydrogen and electricity are excluded from this exemption, but for the main goods categories the Commission estimates the threshold exempts around 90% of importers while still covering roughly 99% of embedded emissions.

Two honest consequences for you as a supplier:

• Whether your customer asks depends on their import volume, not yours. A small EU buyer importing modest quantities may simply be out of scope — and won't need your data at all. It's worth asking before you invest effort.
• The threshold is cumulative and unforgiving. If an importer exceeds 50 tonnes at any point in the year, their whole year's imports become subject to CBAM — not just the excess. Customers near the line may still ask for data as a precaution, and that's a reasonable request.

What your customer actually needs from you

If your customer is in scope, what they need is the embedded emissions of the goods you supply — the greenhouse gases released in producing them, per product. Typically:

• Direct emissions from your production process, and relevant indirect emissions from the electricity used in production.
• Per-tonne (or per-unit) figures for the specific CBAM goods you sell them.
• The calculation method and data behind the figure, so it can withstand scrutiny.

This is closely related to a product carbon footprint — a per-product emissions figure — though CBAM uses its own defined methodology for embedded emissions. If your customer references a specific CBAM data template or methodology, follow it.

Actual values vs default values — why your data matters

In the definitive regime, an importer has two ways to declare embedded emissions:

1. Verified actual values — real production data from the supplier, checked by an accredited verifier.
2. Commission default values — fallback figures based on the average emission intensity of the ten highest-emitting exporter countries for each good, with regional adjustments.

Note the design: defaults are pegged to the worst-performing exporters, not the average producer. If your actual emissions are lower than the default — and for many producers they will be — then supplying verifiable actual data directly reduces your customer's CBAM cost from 2027 onwards. A supplier who can hand over a documented, defensible embedded-emissions figure is cheaper to buy from than one who forces the importer onto punitive defaults. That's not a compliance nicety; it's a competitive edge. Germany's CBAM authority explains the definitive-regime mechanics in detail on the DEHSt CBAM page.

How to prepare the data

1. Confirm scope with your customer — which products, whether they expect to be above the de minimis threshold, and which methodology and template they want.
2. Gather production data — energy and fuel used to make the goods, process emissions, electricity consumption, and output quantities. Our carbon calculator and manufacturing footprint guide cover the operational side.
3. Calculate embedded emissions per unit of the CBAM good, using the method your customer specifies.
4. Document everything — data sources, factors, boundaries, period. If your customer wants to use actual values, the figure has to survive an accredited verifier, not just look plausible.

If you're the EU importer

If you import more than 50 tonnes of CBAM goods into the EU per year, the obligation is yours: you'll need to be an authorised CBAM declarant, declare embedded emissions annually, and buy and surrender certificates once sales start on 1 February 2027. Implementing rules are still being finalised, so check the Commission's CBAM page or an adviser for the current schedule — don't rely on older summaries.

What not to do

• Don't panic-assume you must file. For most suppliers, CBAM is a customer data request, not your filing obligation.
• Don't invent embedded-emissions figures. Actual values must pass accredited verification; use real production data and document your method.
• Don't provide your company footprint when they need product embedded emissions. They're different numbers — give the per-product figure.
• Don't assume your customer is in scope without checking. The 50-tonne de minimis exempts most importers; confirm before you build a big data exercise.

The bottom line

CBAM entered its definitive period in January 2026, with certificate purchases following from February 2027 — and the obligation sits with the EU importer, not with you as a supplier. If your customer imports more than 50 tonnes of CBAM goods a year, they will ask you for defensible, per-product embedded-emissions data — and actual data that beats the default values makes your product cheaper for them to import. Get the production data and method right once, and you can answer every CBAM-driven request that follows.