CBAM 2028: the 30% Mark-up and the Downstream Extension

2028 is when the EU CBAM reaches its intended shape. The penalty on default values stops rising, but the free-allocation deduction keeps shrinking, so every year after 2028 still costs more than the one before. And if the downstream extension is agreed, a much larger group of exporters, those who make goods from steel and aluminium rather than the metal itself, comes into scope in the same year.

What changes on 1 January 2028

Fertilisers keep a 1% mark-up throughout. The CBAM factor follows the EU ETS phase-out of free allocation for the same products; the Commission's ETS review proposal of July 2026 would restore part of the free allocation from 2028 and push the full phase-out to 2038, with agreement targeted for early 2027. Treat 2028 onwards as current law, not a certainty.

The cost curve on default values

Held at the Q3 2026 price of €82.32, 1,000 tonnes would cost about €356,500 in 2028 and €458,000 in 2034, against €277,600 in 2026. The certificate price itself will move. The figures after 2026 also use the benchmarks published today; the Commission is updating them for imports from 2027.

The downstream extension

On 17 December 2025 the Commission proposed extending CBAM from 1 January 2028 to downstream goods with a high steel or aluminium content: fittings, screws, bolts, wire, tubes, radiators, machinery parts and similar products. It would also treat pre-consumer scrap as a precursor, to close a route around the rules.

Trilogue talks began in autumn 2026. The first political meeting, on 20 October, ended without a deal; a second, intended to be final, is set for 30 November. Until it is agreed and published, the list and the 2028 start date are proposals. We follow it in our October CBAM update.

If you make downstream goods

1. 1

   Map your CN codes

   Check each product you export to the EU against the proposed lists. A large share are intermediate industrial goods, often made by small and mid-sized firms.

2. 2

   Find your metal

   A downstream good's embedded emissions are mostly the steel or aluminium in it. Record which supplier and which grade went into each product.

3. 3

   Ask suppliers for their figures

   Your mill's verified specific embedded emissions become your precursor figure. Without them your buyer falls back to the default for the metal.

4. 4

   Add your own process

   Cutting, forming, heat treatment and coating add direct emissions from your fuel and, for some goods, electricity. Those are the part you measure yourself.

5. 5

   Run the numbers both ways

   Compare what your buyer pays on defaults with what your actual data would show, so you know what the data is worth before you invest in it.

The calculator covers goods already in scope. For downstream goods, the default values will be published once the extension is adopted.

What to do in 2026 and 2027

• If you are already in scope: get your 2026 data verified for the first declaration in September 2027 (see CBAM in 2027).
• If you may be in scope from 2028: map CN codes, list metal suppliers and start collecting their emissions figures in 2027.
• In both cases, tell your EU customers early whether they will get actual data from you. Many will decide supplier shares on it.

ZeroCarbon carries precursor figures from your metal suppliers into each product's embedded emissions, keeps the evidence a verifier needs, and prepares the communication to your EU importer. Try the free CBAM cost calculator, or request a workspace to map your products.