Under the definitive CBAM regime, EU importers no longer merely report emissions: they must hold authorised declarant status, buy CBAM certificates, keep a minimum balance in their account and surrender certificates each year matching the embedded emissions of their imports. Certificate prices are not fixed; they track weekly EU ETS auction prices, turning the carbon obligation into a fluctuating financial cost to be managed like an exchange rate. This article guides EU importers, and the Vietnamese suppliers supporting them, through where certificates are bought, how prices are set, the annual surrender calendar and whether a carbon price paid at origin can be deducted. Each element interacts with the importer’s cash flow, as the sections below explain in sequence.
1. Applicable legal framework
The framework is Regulation (EU) 2023/956 on CBAM, with the definitive regime applying from 1 January 2026 to the Annex I goods. CBAM certificates are purchased on the EU common platform through the authorised declarant’s account in the CBAM Registry; the certificate price follows the average EU ETS auction price published by the European Commission for the relevant period. The declarant files the annual CBAM declaration for the preceding year by 31 May and surrenders the corresponding certificates, maintains the prescribed minimum account balance during the year, and may claim a deduction for a carbon price effectively paid in a third country under the regulation’s mechanism where evidence is sufficient.
2. Where certificates are bought and the authorised declarant account
CBAM certificates are not freely traded on a secondary market like ETS allowances: only authorised declarants can buy them, through their own account on the common platform operated within the CBAM Registry system by EU member states. Authorised declarant status is a precondition tied to the customs treatment of CBAM goods; an importer without that status cannot complete the obligation and should not wait until goods reach port before applying.
A Vietnamese supplier is not the certificate buyer, unless it imports into the EU through its own EU entity. The supplier’s real role is to deliver verified embedded-emissions data so the importer can calculate how many certificates to buy. The contract should settle the data delivery calendar, responsibility where EU authorities reject data, and how certificate cost movements are shared, because the purchase sits with the importer while the cost driver is the product’s carbon intensity.
3. Certificate pricing, quarterly balance and the annual surrender
One CBAM certificate corresponds to one tonne of embedded CO2, and its price is set from the average EU ETS auction price published for the period, so it moves with the European carbon market rather than any fixed official tariff. Importers should budget carbon as a variable cost line, watch ETS prices and plan purchase timing within the rules, instead of assuming one nominal price for the whole financial year.
The operating rhythm has two beats: during the year, the declarant keeps the account balance at or above the prescribed minimum linked to the embedded emissions of goods already imported; at cycle end, the declarant files the CBAM declaration for the previous year by 31 May and surrenders the matching certificates, with any surplus handled under the regulation’s limited buy-back mechanism. Missing certificates or a wrong declaration exposes the declarant to penalties under member-state law and scrutiny of its authorised status.
4. Deducting a carbon price paid at origin, and supplier actions
The CBAM regulation allows a deduction for a carbon price effectively paid in the country of origin, so the same emissions are not charged twice. The conditions are that the price was genuinely paid, is evidenced, and was not rebated or offset through another mechanism. At the time of writing, Vietnam does not yet operate an ETS-equivalent carbon pricing system across the CBAM sectors at general scale, so the practical deduction available to Vietnamese goods remains limited and must be assessed case by case as the domestic carbon market takes shape.
The most useful step a Vietnamese supplier can take now is to cut actual embedded emissions and prove the reduction with verified data, because every tonne of CO2 avoided is a certificate the importer need not buy at any ETS price. Suppliers should invest in product-level measurement, independent verification and a quarterly data rhythm agreed with EU customers. In price negotiations, a credible carbon dataset is becoming part of the commercial terms, on a par with quality and delivery reliability.
5. Quick answers
Through which EU mechanism are CBAM certificates bought?
Certificates are bought on the EU common platform through the authorised declarant’s account in the CBAM Registry, a status the importer must hold to bring CBAM goods into the EU under the definitive regime. Certificates are not freely traded on a secondary market like ETS allowances and remain attached to the declarant’s account.
How does the CBAM certificate price relate to the EU ETS carbon price?
One certificate, covering one tonne of embedded CO2, is priced from the average EU ETS auction price published by the European Commission for the relevant period, so it fluctuates with the European carbon market. Importers must budget carbon as a variable cost, follow ETS prices when planning purchases, and maintain the prescribed minimum certificate balance in their account throughout the import year.
When must importers surrender certificates each year?
The authorised declarant files the CBAM declaration for the preceding calendar year by 31 May of the following year and surrenders certificates matching the declared embedded emissions at the same time. During the year, the account must stay at or above the prescribed minimum balance linked to goods already imported. Late.
Can a carbon price paid in Vietnam be deducted?
The CBAM regulation permits deducting a carbon price effectively paid in the country of origin, provided it is evidenced and was not rebated. However, at the time of writing Vietnam does not yet run an equivalent carbon pricing system across the CBAM sectors at scale, so the practical deduction for Vietnamese goods is still very limited.
This article has been quality-reviewed by the FLAW AI Legal Council
