Glossary
Verifier – EU ETS
Under the EU Emissions Trading System (EU ETS), the accredited legal person, or otherwise authorised natural person, that checks yearly emissions reports and free allocation data. A yearly emissions report must be verified as satisfactory by 31 March.
- Who it applies to
- Verification companies accredited under the Accreditation and Verification Regulation. Operators of installations and aircraft operators must have each yearly emissions report verified, and installations applying for or receiving free allocation also have their baseline data and activity level reports verified. For ships, the maritime monitoring rules define a verifier of their own.
- Example
- An installation reports 12,000 tonnes of CO₂ equivalent (CO₂e) for 2026. If the report hasn't been verified as satisfactory by 31 March 2027, the operator can't make further transfers of allowances until it is. By 30 September 2027, it must surrender 12,000 allowances.
- Also known as
- EU ETS verification body, accredited verifier (EU ETS), ETS verifier
The Accreditation and Verification Regulation (Implementing Regulation (EU) 2018/2067) defines a verifier as a legal person carrying out verification activities under that Regulation and accredited by a national accreditation body, or a natural person otherwise authorised, at the time a verification report is issued.
Verifiers check operators' and aircraft operators' yearly emission reports, and the data used to update benchmarks and determine
Ships follow the maritime monitoring rules, which define a verifier as a legal entity accredited by a national accreditation body under those rules.
Under the Carbon Border Adjustment Mechanism (CBAM), verifiers need a CBAM accreditation: an EU ETS accreditation is taken into account and can be extended to the matching CBAM activity groups, but doesn't replace it. See
Our explainer on the yearly compliance cycle takes each step, from the
Regulations
EU Emissions Trading System (EU ETS)
Implementing Decision (EU) 2026/1862 set the cross-sectoral correction factor for free allocation at 100% for each year from 2026 to 2030
Used in
EU ETS compliance deadlines: monitor, verify and surrender allowances each year
EU ETS operators must report verified emissions by 31 March and surrender allowances by 30 September. Each step, who acts, and what a shortfall costs.