Skip to main content
Climate Action

The Union Registry serves to guarantee accurate accounting for all allowances issued under the EU emissions trading system (EU ETS). The registry keeps track of the ownership of allowances held in electronic accounts, just as a bank has a record of all its customers and their money.

On 14 July 2021, the European Commission adopted a series of legislative proposals setting out how it intends to achieve climate neutrality in the EU by 2050, including the intermediate target of an at least 55% net reduction in greenhouse gas emissions by 2030. The package proposes to revise several pieces of EU climate legislation, including the EU ETS, Effort Sharing Regulation, transport and land use legislation, setting out in real terms the ways in which the Commission intends to reach EU climate targets under the European Green Deal.

A single EU registry

In 2012, EU ETS operations were centralised into a single EU registry operated by the European Commission. The Union Registry covers all countries participating in the EU ETS.

The Union Registry is an online database that holds accounts for stationary installations (transferred from the national registries used before 2012) and for aircraft operators (included in the EU ETS since January 2012).

The Registry records:

  • National implementation measures (a list of installations covered by the ETS Directive in each EU country and any free allocation to each of those installations in the period 2013-2020)
  • Accounts of companies or individuals holding such allowances
  • Transfers of allowances ("transactions") performed by account holders
  • Annual verified CO2 emissions from installations and aircraft operators
  • Annual reconciliation of allowances and verified emissions, where each company must have surrendered enough allowances to cover all its verified emissions.

Opening accounts in the Union registry

To participate in the EU ETS, companies or individuals have to open an account in the Union Registry.

To open an account, they must send a request to the national administrator, who collects and checks all supporting documentation.

European Union Transaction Log

The European Union Transaction Log (EUTL) automatically checks, records and authorises all transactions between accounts in the Union Registry. This ensures that all transfers comply with EU ETS rules.

The EUTL is the successor of the Community Independent Transaction Log (CITL), which had a similar role before the Union Registry was introduced.


Click on the + signs for more information.


Click on the + signs for more information.


Questions & answers on implementation of new rules due to Delegated Regulation (EU) 2019/1122

Kyoto Protocol registries

ETS accounts

International credits


Account representatives


Data protection

Questions & answers on technical requirements to use the Union Registry

Questions & answers on implementation of new registry rules regarding units from Joint Implementation (02/2013)

See the FAQ on International Carbon Market

General Questions and Answers on Registries (05/2013)

Questions and Answers on the use of the Union registry for airlines (05/2013)

Questions and Answers on banking of emission allowances and exchange of international credits (05/2013)

Questions and Answers on the activation of the trusted account list and trading accounts (31/08/2012)


Click on the + signs for more information.