The Carbon Border Adjustment Mechanism (CBAM) is established under Regulation (EU) 2023/956 to require importers of certain goods into the European Union to declare embedded carbon emissions and surrender corresponding CBAM certificates. Importers may declare emissions based on either default values published by the European Commission or verified actual emissions data from their suppliers. The latter requires third-party verification by an accredited verifier under Commission Implementing Regulation (EU) 2023/1773. This page compares the two approaches—self-declaration using default values versus third-party verification of actual emissions—highlighting their scope, obligations, timelines, penalties, and enforcement to guide importers on compliance under CBAM.
Self-Declaration vs Third-Party Verification for CBAM
The key difference between self-declaration and third-party verification under CBAM is that self-declaration allows importers to use Commission-published default carbon intensity values without external validation, while third-party verification requires accredited verifiers to confirm actual emissions data from suppliers. Self-declaration is simpler but may lead to higher CBAM costs and penalties if emissions are understated. Third-party verification can reduce CBAM costs by using lower actual emissions but involves additional procedural and accreditation requirements.
| Dimension | Self-Declaration (Default Values) | Third-Party Verification (Actual Emissions) |
|---|---|---|
| Scope | Importers may use default carbon intensity values published by the European Commission per product and country of origin. | Importers use actual emissions data provided by suppliers, which must be verified by an accredited third-party verifier. |
| Obligations | Declare emissions based on default values; no external verification required. | Obtain verification from an accredited verifier under Commission Implementing Regulation (EU) 2023/1773 confirming accuracy of actual emissions data. |
| Verification Requirements | None; importer self-declares using published default values. | Mandatory third-party verification by verifiers accredited under EU ETS rules (Regulation (EU) 2018/2067). |
| Timeline | Allowed during transitional phase (2023-2025) and beyond. | Verification required from 1 January 2026 when full CBAM obligations, including certificate surrender, commence. |
| Penalties for Understatement | €50-150 per tonne CO2 undeclared plus potential criminal liability if emissions are understated. | Same penalties apply if verified emissions are found inaccurate or falsified. |
| Enforcement Authority | EU Member State customs and environmental authorities enforce compliance. | Same enforcement authorities, with additional oversight of accredited verifiers. |
| Cost Implications | Potentially higher CBAM costs due to conservative default values. | Potential cost savings if actual emissions are lower than default values, offset by verification fees. |
Where Self-Declaration and Third-Party Verification Overlap and Diverge
Both self-declaration and third-party verification serve to quantify embedded emissions in imported goods under CBAM Regulation (EU) 2023/956. They overlap in the requirement to report emissions accurately and surrender CBAM certificates (post-transitional phase). However, they diverge significantly in the source and validation of emissions data:
- Data Source: Self-declaration relies on standardized default values, while third-party verification uses supplier-specific actual emissions data.
- Verification: Self-declaration requires no external verification; third-party verification mandates accredited verifier involvement.
- Risk Profile: Self-declaration carries a higher risk of penalties if default values underestimate actual emissions or if importers attempt to underreport. Third-party verification reduces this risk by providing validated data.
- Cost and Complexity: Self-declaration is simpler and less costly upfront but may result in higher CBAM payments. Third-party verification involves additional procedural steps and costs but can yield financial benefits through lower reported emissions.
Which Approach Applies to You?
Your choice between self-declaration and third-party verification depends on your company's import profile, risk tolerance, and cost-benefit analysis:
- Use Self-Declaration if you import goods covered by CBAM but lack detailed emissions data from suppliers or prefer a simpler compliance route during the transitional phase (2023-2025).
- Use Third-Party Verification if you have access to actual emissions data from suppliers and want to minimize CBAM costs by demonstrating lower emissions than default values, especially after 1 January 2026 when full obligations apply.
- Note that from 1 January 2026, importers must surrender CBAM certificates based on declared emissions, making accurate verification critical to avoid penalties.
Importers should also consider the accreditation status of verifiers and ensure compliance with Commission Implementing Regulation (EU) 2023/1773 and Regulation (EU) 2018/2067 for verification processes.
Truth Anchor: Under Regulation (EU) 2023/956, the transitional phase for CBAM runs from 1 October 2023 to 31 December 2025, during which importers submit quarterly emissions reports without surrendering certificates. Full obligations, including certificate surrender and mandatory third-party verification of actual emissions, commence on 1 January 2026. Penalties for underreporting emissions range from €50 to €150 per tonne CO2 undeclared, as stipulated in Article 21 of the CBAM Regulation.
Internal Links for Further Compliance Guidance
Frequently Asked Questions: Self-Declaration vs Third-Party Verification for CBAM
1. Is self-declaration allowed after the transitional phase ends on 31 December 2025?
No. From 1 January 2026, importers must surrender CBAM certificates based on declared emissions. If actual emissions data is used, it must be verified by an accredited third-party verifier under Commission Implementing Regulation (EU) 2023/1773. Self-declaration using default values remains possible but may lead to higher CBAM costs.
2. What happens if I understate emissions in my CBAM declaration?
Understating emissions can result in penalties ranging from €50 to €150 per tonne CO2 undeclared, plus potential criminal liability depending on the severity and intent, as per Article 21 of Regulation (EU) 2023/956. Both self-declared and verified emissions are subject to these penalties if found inaccurate.
3. Who accredits the third-party verifiers for CBAM actual emissions?
Verifiers must be accredited under the EU Emissions Trading System (EU ETS) verification rules established by Regulation (EU) 2018/2067. Accreditation is overseen by national accreditation bodies within EU Member States.
4. Can I switch between self-declaration and third-party verification year to year?
Yes, importers may choose to use default values or verified actual emissions each reporting period. However, once opting for actual emissions, all data must be verified by an accredited verifier to comply with CBAM rules.
5. How do default values compare to actual emissions data?
Default values are conservative estimates published by the European Commission per product and country of origin. Actual emissions data, when verified, often reflects lower emissions specific to the supplier's production process, potentially reducing CBAM costs.
Next Step: Use Our CBAM Emissions Verification Tool
Clicking the button below will take you to our CBAM Emissions Verification Tool, which helps you determine whether self-declaration or third-party verification is most cost-effective and compliant for your imports. The tool guides you through inputting your product details, supplier emissions data, and calculates potential CBAM liabilities and penalties.
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