Transactions and trading

Transfers in the Union Registry are governed by a regulatory framework. A transaction refers to all transfers of units to or from an account. For instance, deletion or surrendering of allowances is classified as transactions. Emissions trading can take place in different ways.


Transfers between accounts

Transfers of allowances can be made between accounts of different types in the EU ETS and to accounts in the Swiss registry. Other unit types may, with certain restrictions, be transferred between accounts in the EU ETS, in the registry under the Kyoto Protocols and, in some cases, other Emissions Trading Systems.

The Union Registry is from 1 January 2020 linked to the Swiss national emissions trading system.

The transfers are carried out by the representative of the transferring account holder who specifies the amount of transfer. How quick the transferred units are delivered to the recipient account depends on the account type and delays.


Several transfer types require approval by a second representative. All transfers also require 2-factor authentication through password and a one-time code sent as SMS (valid until 31 December 2021) or approval via the EU Login mobile app.


Issuance and allocation

According to Swedish regulations (Förordning (2020: 1180) om vissa utsläpp av växthusgaser), the Swedish Energy Agency must allocate allowances every year no later than 30 June in the year to which the allocation relates. The allocation may in certain cases be delayed if the Swedish Environmental Protection Agency intends to make an amendment decision.

In the fourth phase of the Emissions Trading Scheme (2021-2030), all allowances are first issued on central EU accounts by the European Commission in its role as the Central Administrator of the Union Registry. Free allocation is transferred to installations following an approved application.

Phase 4 is divided into two allocation periods and two application rounds. The allocation periods are 2021-2025 and 2026-2030 and operators with installations that are entitled to free allocation can apply before the respective allocation period begins. The quantities are specified in national distribution tables and are based on benchmarks.

Swedish Environmental Protection Agency: Information on free allocation of allowances to installations for phase 4 (2021–2030) (In Swedish)

Decisions on free allocation for the period 2021-2025 have been made by the Swedish Environmental Protection Agency and the Swedish Energy Agency has allocated the allowances in the Union Registry.

In the third period of the Emissions Trading Scheme (2013-2020), all allowances were issued by the European Commission in its role as the Central Administrator of the Union Registry. The quantities were specified in national allocation tables (NAT = National Allocation Table) and were based on benchmarks.

Information on free allocation of allowances to installations for phase 4 (2021–2030) (In Swedish)

In the second period of the Emissions Trading Scheme (2008-2012), emission allowances were issued and allocated by Member States. The quantities were specified in the National Allocation Plan (NAP) and the units were stored in national accounts before being allocated.

The central administrator is responsible for transactions of allowances to auctions and to installations entitled to free allocation. Member States are responsible for implementing the allocation.


Surrender of allowances

By 30 September each year, operators included in the EU ETS must surrender allowances corresponding to the verified emissions for the previous year. The transaction is carried out in the Union Registry.

According to Directive (EU) 2018/410 of the European Parliament and of the Council allowances issued from 1 January 2013 shall be valid indefinitely. Allowances issued from 1 January 2021 are according to Commission Delegated Regulation (EU) 2019/112 valid for emissions from 2021, the first year of the fourth ETS phase.

This means that allowances issued from 2021 onwards cannot be used for compliance regarding 2020 emissions, while allowances issued 2020 or earlier (ETS phase 3) can be used for compliance during the fourth trading period, i.e., from 2021.

The units are marked in the Union Registry with ETS phase 3 for units issued before 2021 and ETS phase 4 for units issued from 2021.

When surrendering, operators can use general allowances or aviation allowances. Swiss allowances can also be used when surrendering for compliance.

If a sufficient amount of allowances is not surrendered by April 30, a fee of 100 € per tonne of carbon dioxide equivalent emissions which is not covered by the surrender. Also, the fee does not remove the obligation to surrender the missing amount at a later date.


Deletion of units

Participants in the trading system may choose to voluntarily delete units, in other words, permanently remove them from the market as a climate measure. For accounting purposes, any deleted units will disappear from the market into a dedicated deletion account. Deleted units can never be brought back into the market from the deletion account.

Removing units from the market reduces the number of units available for compensating emissions and, in theory, increases the price of emissions in the ETS.


International credit transactions

International credits cannot be transferred between EU ETS accounts.

From 1 May 2021, incoming transactions to an EU ETS account containing these units will not be allowed. The units can from then on only be cancelled, deleted or transferred to an account outside the EU ETS. International credits can be held in EU accounts until 1 July 2023.

International credits can be transferred from an EU ETS account to a person holding account under the Kyoto protocol where the units are allowed.


Exchange of international credits

Until 30 April 2021, it was possible for certain operators to exchange international credits for general allowances or aviation allowances.

Unit types

The number of credits allowed to be exchanged was decided by the Swedish Environmental Protections Agency based on the so-called RICE-regulation.

Legislation and references

The exchange was carried out through a specific transaction type in the Union Registry where the credits were transferred to a specific EU account and a corresponding number of allowances or aviation allowances were transferred back to the initiating account.

The possibility to exchange international credits originating in the first commitment period under the Kyoto Protocol was removed 1 April 2015.

The possibility to exchange international credits originating in the second commitment period under the Kyoto Protocol was removed 30 April 2021.

Any unused remaining exchange limit was removed from the account after 30 April 2021.

Different ways of trading in allowances



Auctioning is an efficient way of distributing allowances to the market. The Commission estimated that 57% of the total amount of general allowances (EUA) was auctioned in phase 3. During phase 4 (2021-2030), the proportion of allowances to be auctioned remains the same. Both EUA and EUAAs are auctioned off.

The European Energy Exchange (EEX) is currently the common auction platform. More information about the auction process, including the auction calendar and fees, can be found on the EEX website.

The European Energy Exchange (EEX)

The auctioning is regulated by the Auctioning Regulation (1031/2010/EU). According to this regulation, the following entities may apply for permission to place bids directly in auctions:

a) an operator or an aircraft operator having an operator holding account or an aircraft operator holding account, bidding on its own account, including any parent undertaking, subsidiary undertaking or affiliate undertaking forming part of the same group of undertakings as the operator or the aircraft operator;
b) investment firms authorised under Directive 2014/65/EU bidding on their own account or on behalf of their clients;
c) credit institutions authorised under Directive 2013/36/EU of the European Parliament and of the Council bidding on their own account or on behalf of their clients;
d) business groupings of persons listed in point (a) bidding on their own account and acting as an agent on behalf of their members;
e) public bodies or state-owned entities of the Member States that control any of the persons listed in point (a).

Information on auctioning on the European Commission website


Over-the-counter (OTC)

Emissions trading can take place directly between two parties, this is called OTC trading (over-the-counter trading). For example, a buyer who has a deficit of allowances can purchase allowances from a company that has a surplus. Trading can also take place through brokers (e.g., banks). In principle, anyone with an account in the Union Registry can trade OTC.

The EUTL website provides general information on EU ETS participants who may be involved in trade.