One of the most common sources of confusion about CBAM is the question of who is responsible for what. CBAM creates a clear division of labour between two parties: EU importers (who hold the legal compliance obligation) and non-EU exporters (who hold the data that determines the actual cost). Both parties have critical roles, but they are entirely different in nature.
Understanding this division is important whether you are an EU company importing from abroad, a non-EU manufacturer supplying to EU customers, or an intermediary (trader or customs agent) caught between both.
1. CBAM obligations: the two parties
CBAM Regulation (EU) 2023/956 creates obligations on EU importers — specifically the entity that is legally responsible for the customs declaration when goods enter the EU. There is no direct legal obligation under EU CBAM on the non-EU exporter.
However, the importer's ability to comply cost-efficiently depends entirely on the exporter. The importer must surrender CBAM certificates equal to the embedded emissions in their imports. Those embedded emissions can be either: (a) actual values provided by the exporter, or (b) default values set by the European Commission. Default values are intentionally punitive — they represent the 90th percentile of global emissions intensity for the product category.
This creates a strong commercial incentive for importers to require accurate embedded emissions data from exporters, and for exporters to invest in calculating and documenting their actual emissions.
2. EU importer (authorised declarant) obligations
The EU importer must become an Authorised CBAM Declarant before importing covered goods. Authorisation is granted by the national competent authority (in the UK, HMRC; in Germany, the Federal Environment Agency; etc.) and involves registration in the CBAM registry.
Ongoing obligations for authorised declarants include:
- Pre-import: registration — must obtain authorised declarant status before importing any CBAM goods from January 2026
- During the year: certificate purchase — purchase CBAM certificates throughout the year proportional to expected import volume; certificates are priced weekly at the EU ETS average
- Annual CBAM declaration — file the annual CBAM declaration by 31 May each year, covering all CBAM imports in the previous calendar year; declaration must include embedded emissions per shipment and per product type
- Certificate surrender — surrender certificates equal to the total embedded emissions declared by 31 May; excess certificates may be carried forward; insufficient certificates are subject to penalty
- Verification — ensure that actual embedded emission values have been verified by an accredited third-party verifier; default values do not require verification
- Record retention — retain all CBAM records for at least 4 years after the declaration year
- Quarterly purchase monitoring — maintain certificate holdings at or above expected annual obligation; avoid end-of-year cash flow squeeze
Penalties for non-compliance: failure to surrender sufficient certificates results in a penalty equal to three times the CBAM certificate price per tonne of shortfall, plus an obligation to surrender the missing certificates.
3. Non-EU exporter obligations
Non-EU exporters have no direct legal obligations under CBAM. They are not required by EU law to register, file declarations, or purchase certificates. However, commercial necessity makes their role critical:
- Embedded emissions calculation — calculate actual direct and indirect embedded emissions per tonne of goods using the CBAM Implementing Regulation (EU) 2023/1687 methodology; cover all production processes at the installation level
- Monitoring plan — establish a monitoring plan documenting how energy, fuel, and process data are collected and used in the calculation; the monitoring plan is reviewed by the third-party verifier
- Third-party verification — engage an accredited verifier (ISO 14065 / EU ETS accreditation standard) to verify the embedded emission calculation; provide a verification report to the EU importer
- Emission data communication — communicate actual embedded emissions in the format required by the CBAM declaration, per shipment or per periodic batch as agreed with the importer
- Carbon price documentation — if a carbon price has been paid in the country of production, document it for the importer to claim a deduction
- Record retention — retain calculation records and monitoring plan documents for a minimum of 5 years (CBAM minimum; longer if required by own jurisdiction)
4. Side-by-side comparison
| Obligation | EU Importer (Authorised Declarant) | Non-EU Exporter |
|---|---|---|
| Legal responsibility under CBAM | Direct; under Regulation (EU) 2023/956 | None (indirect via commercial relationship) |
| Registration | Must register as Authorised CBAM Declarant | No EU registration required |
| Emissions calculation | Receives from exporter or uses defaults | Must calculate at installation level |
| Monitoring plan | Not required | Must establish and maintain |
| Third-party verification | Must ensure actual values are verified | Must engage and coordinate verifier |
| Certificate purchase | Yes — purchases certificates at EU ETS price | No certificate purchase |
| Annual declaration | Yes — by 31 May each year | No EU declaration |
| Carbon price deduction | Claims deduction in declaration | Provides documentation of carbon price paid |
| Penalty exposure | 3× certificate price per tonne shortfall | Commercial risk only (loss of competitiveness if defaults used) |
| Record retention | 4 years | Minimum 5 years (CBAM) |
5. CBAM certificates: how they work
CBAM certificates are distinct from EU ETS allowances. They are purchased by authorised declarants from national authorities, priced weekly at the EU ETS average closing price for the previous calendar week. Each certificate covers one tonne of CO₂e embedded in imported goods.
Key features of CBAM certificates:
- Non-tradeable — CBAM certificates cannot be sold or transferred between declarants; they are company-specific
- Buyback provision — national authorities will buy back up to one-third of certificates purchased in a year at the original purchase price, providing some hedge against over-purchasing
- Annual surrender — certificates must be surrendered by 31 May for the previous calendar year's imports; certificates not surrendered by this date are cancelled and the shortfall is penalised
- Price volatility — certificate prices track EU ETS prices, which have ranged from €25 to €105/tonne CO₂e in recent years
6. Default values vs. actual emissions: the financial case
The financial difference between using default and actual embedded emission values is often the most compelling argument for exporters to invest in CBAM compliance work. The table below illustrates the potential cost difference for a typical steel exporter:
| Scenario | Embedded emissions | CBAM cost at €65/tCO₂e | Per tonne of steel |
|---|---|---|---|
| Default value (basic oxygen furnace, typical) | ~2.5 tCO₂e/t steel | €162.50/t steel | Paid by importer |
| Actual value (modern EAF, grid electricity) | ~0.5 tCO₂e/t steel | €32.50/t steel | Paid by importer |
| Difference (100,000 t export) | 2.0 tCO₂e/t | €13,000,000 |
On a 100,000-tonne steel export to the EU, the difference between default and actual values represents €13 million in annual CBAM certificate costs for the importer. That importer will either absorb this cost (reducing margin), pass it to the buyer (reducing competitiveness), or source from a lower-emission exporter who provides verified actual values. The commercial pressure to provide actual emission data is therefore enormous.
7. Key dates for 2025–2027
| Date | Obligation | Who |
|---|---|---|
| 1 January 2026 | Definitive phase begins; certificate purchase obligation starts | EU importers |
| 1 January 2026 | Only authorised declarants may import CBAM goods | EU importers |
| Q1 2026 | First certificate purchases for 2026 imports | EU importers |
| 31 May 2026 | First CBAM declaration for calendar year 2025 (transitional data) — timing TBC | EU importers |
| 31 May 2027 | First full definitive CBAM declaration for calendar year 2026 | EU importers |
| Ongoing 2026+ | Exporter actual emission data + verification reports to importers | Non-EU exporters |
Need CBAM compliance support — importer or exporter?
Our CBAM Compliance service supports both EU importers (declaration preparation, registry, certificate management) and non-EU exporters (embedded emissions calculation, monitoring plan, verifier coordination). One team, both sides of the border.
View CBAM Compliance Service →FAQs
Who is legally responsible for CBAM compliance?
The EU importer (authorised declarant) holds the legal obligation — they register, file the declaration, purchase, and surrender certificates. The non-EU exporter has no direct EU legal obligation but is commercially essential because their embedded emissions data determines the certificate cost. Without actual verified data, importers use punitive default values.
What must a CBAM authorised declarant do?
Register before first CBAM import, purchase certificates at the weekly EU ETS price throughout the year, file annual CBAM declaration by 31 May, surrender certificates equal to declared embedded emissions, ensure actual values are third-party verified, and retain records for 4 years.
What must a non-EU exporter do for CBAM?
Calculate actual embedded emissions per tonne using CBAM Implementing Regulation methodology, establish a monitoring plan, engage an accredited third-party verifier, provide emission data and verification report to EU importer customers, and document any carbon price paid for potential deduction.
What are CBAM certificates and how are they priced?
CBAM certificates are company-specific, non-tradeable instruments covering 1 tonne CO₂e each. Priced weekly at the EU ETS average closing price for the previous week. Purchased from national authorities; up to one-third can be bought back annually. Must be surrendered by 31 May each year for the previous calendar year's imports.