The European Commission is set to release the final rules that complete the implementation of the EU’s Carbon Border Adjustment Mechanism (CBAM) in the last two months of the year, according to Carbon Pulse. Additional rules for extending CBAM to downstream products are expected to follow in 2027. For importers, EU buyers of CBAM-covered goods and investors tracking allowance demand, the sequence matters because the mechanism is already in its definitive phase while key technical details are still being finalised.

What Is Coming and When

The report describes two steps. The first is a set of final rules to complete CBAM implementation, due in the closing two months of the year. The second is a further set of rules for the downstream extension, due in 2027.

The source text available to us is brief and does not list which acts will be released. It also gives no exact publication dates. Readers should treat the timing as a window, not a date.

The Starting Point: A Compliance Phase Already Running

CBAM entered its definitive phase on 1 January 2026, ending the 2023-2025 transitional period, according to ICAP. Importers bringing in 50 tons or more of CBAM-covered goods per year must declare embedded emissions and surrender the corresponding CBAM certificates the following September. The first declaration and surrender deadline is 30 September 2027, for emissions embedded in imports during 2026.

On 16 December 2025 the Commission published a review report on the transitional period, together with eight implementing acts and two legislative proposals. The acts cover, among other topics:

  • the calculation methodology for embedded emissions;
  • default values;
  • the price of CBAM certificates;
  • verification principles for declared emissions;
  • authorisation of CBAM declarants;
  • the CBAM registry.

Pricing and Benchmarks Still in Motion

Several parameters are tied to dates that fall close to the expected final rules. For 2026, the CBAM certificate price is based on the quarterly average of EU allowance auction prices. From 2027 it moves to the weekly average of auction prices. Sales of CBAM certificates begin on 1 February 2027.

CBAM benchmarks mirror the current EU ETS free allocation benchmarks. ICAP notes they will be reviewed and updated until 1 January 2027 to align with the final ETS benchmarks for 2026-2030. It adds that the 2026 benchmarks are lower and more stringent than in the Commission’s initial proposal.

ICAP also lists the methodology for deducting carbon prices effectively paid in third countries among the items on the path ahead. For exporters facing a carbon price at home, that methodology determines how much of the cost can be recognised.

The Downstream Extension Is Still in Negotiation

The 2027 rules depend on a legislative file that is not yet settled. On 17 December 2025 the Commission proposed amendments to extend CBAM to downstream goods and to strengthen anti-circumvention measures, according to Mayer Brown. The extension would cover approximately 180 downstream product types, predominantly steel and aluminium-intensive goods such as screws, bolts, wire, tubes and metal furniture.

The Council agreed its general approach on 12 June 2026, and the European Parliament adopted its mandate in plenary on 15 September 2026. Trilogue talks were underway at technical level, with the first political trilogue scheduled for 20 October 2026. The material does not report the outcome of that meeting, so the final scope and timing of the extension remain open.

Implications for Importers and Investors

For importers, the main task is to keep declarations and data collection aligned with a rulebook that is still being finished. Default values, verification principles and the registry are part of the existing package, but the final rules may refine how they apply in practice.

For companies whose products may fall into the downstream list, the 2027 rules are the ones to monitor. The extension to roughly 180 product types would widen the group of goods carrying a carbon cost at the border, though only if the legislative process confirms it.

For investors, free allocation is the other lever. For 2026 and 2027, free EU allowances for eligible producers in CBAM-covered sectors fall by 2.5% annually as CBAM takes effect, according to ICAP. The material does not quantify what this means for allowance demand.

What to Watch

  • The publication of the final implementing rules in the last two months of the year.
  • The outcome of the trilogue negotiations on the downstream extension and anti-circumvention measures.
  • The update of CBAM benchmarks ahead of 1 January 2027.
  • The start of CBAM certificate sales on 1 February 2027.
  • The first declaration and surrender deadline on 30 September 2027.

The direction is set, but the details are still being written. Companies that treat the coming rules as a final check on their 2026 data, and not as a new starting point, will be better placed for the first surrender in 2027.