The carbon border adjustment mechanism entered its definitive phase at the start of 2026. Most explanations of it are written for European importers. This one is written for the Chinese supplier on the other end, because that is where the numbers have to come from.
Who owes what
The obligation sits entirely with the importer established in the European Union, or their indirect customs representative. You owe nothing to the European treasury and you file nothing. What you are is the source of the data — and without it your customer cannot complete their declaration.
The scope is narrow and industrial: iron and steel, aluminium, cement, fertilisers, electricity, hydrogen. If you sell a finished consumer product, you are outside it today. If you sell a steel or aluminium part, you are inside it, and so is anyone buying from you.
The commercial consequence, which is the real subject
Your customer's cost now depends on the emissions embedded in what you sell them. Two suppliers with the same price are no longer the same price. The one who can document a lower carbon intensity, with figures that survive scrutiny, is cheaper in the only calculation that matters to the buyer.
There is a second lever that Chinese suppliers use too rarely: carbon costs already paid in the country of production are deductible. If your site is covered by a domestic emissions scheme, that is a documented reduction for your customer. Nobody will ask you for the evidence. You have to offer it.
What to prepare now
- Emissions data per product, not per site. A plant average is not usable; your buyer declares goods, not factories.
- The method behind the figure, written down. A number without a method is refused, and the refusal arrives months later.
- Evidence of any carbon price already paid upstream, in a form a European administration can read.
- A named person who answers these questions. Buyers give up on suppliers who route them to a generic mailbox.
An extension of the mechanism to downstream products has been proposed and is still being negotiated between the European institutions. Nothing is settled: neither the list of products nor the date. Treat it as a direction of travel worth preparing for, not as a rule to comply with yet.
Where to read it yourself
Official pages, opened and checked on 26 September 2026. Where a rule changes, these are the addresses that change with it — this article does not.