European Union Emissions Trading System (EU ETS) is the cornerstone of the European Union's policy to tackle climate change and its key tool for cost-effective reduction of emissions of carbon dioxide (CO2) and other greenhouse gases (GHG) in the power, aviation and industrial sectors.




The EU ETS was launched in 2005 and is the first - and still by far the largest - international system for trading greenhouse gas emission allowances covering over three-quarters of the allowances traded on the international carbon market.


The EU ETS operates in the 27 Member States of the EU, Iceland, Liechtenstein and Norway, as well as in the United Kingdom until the end of 2020 (from 1 January 2021, the EU ETS Directive applies to and in the UK in respect of the generation of electricity in Northern Ireland, on the basis the Protocol on Ireland/Northern Ireland).


As of 1 January 2020, the EU ETS is also linked to the Swiss carbon market.


It regulates emissions from nearly 11 000 power plants and manufacturing installations as well as around 600 aircraft operators flying from/to EEA's airports.


It covers around 38% of the EU's GHG emissions (Report of 18 November 2020 on the functioning of the European carbon market, COM(2020) 740 final).


EU Member States may add more sectors and greenhouse gas emissions to the EU ETS (opt-in procedure).


The EU ETS works on the 'cap and trade' principle and is a market-based measure where participants are required to monitor and report their emissions and surrender sufficient emission allowances to cover their reported emissions in each year.


Emission allowances can be traded to enable abatement to occur where it is most cost effective to do, thereby lowering the overall cost of tackling climate change.


The EU ETS was designed as a quantitative instrument in which a predetermined quantity of emission allowances is released to reach the desired environmental aim, which, under Article 1 of the EU ETS Directive, is ‘to promote reductions of greenhouse gas emissions in a cost-effective and economically efficient manner’ (European Court of Justice in the judgment of 21 June 2018, Republic of Poland v European Parliament and Council of the European Union, Case C-5/16).


European Court of Justice assessed in the said judgment of 21 June 2018 that the system “does not intervene directly to set the price of allowances, the latter being determined exclusively by market forces, on the basis of, inter alia, the scarcity of allowances, combined with the flexibility provided by the possibility of trading allowances.”


The price signal created at EU level is supposed to influence the operational and strategic decisions of investors.



EU ETS cap



A 'cap' is an absolute quantity of greenhouse gases which can be emitted by the factories, power plants and other installations in the system, to ensure the emission reduction target is met.


The cap corresponds to number of allowances put in circulation over a trading phase (period).


In phases 1 and 2 (2005 - 2012) the EU-wide cap was determined in a bottom-up manner from the aggregated total quantity of allowances laid down by Member States in their National Allocation Plans (NAPs).


As from the start of the phase 3, an EU-wide cap is determined by the EU ETS Directive.


The 2013 cap for emissions from stationary installations was set at 2 084 301 856 allowances.


This cap decreased in each year of the phase 3 by a linear reduction factor of 1.74% of the average total quantity of allowances issued annually in 2008-2012, thus ensuring that the number of allowances that can be used by stationary installations will be 21% lower in 2020 than in 2005.


The inherent assumptions were that in 2020 emissions from sectors covered by the EU ETS would be 21% lower than in 2005 and by 2030 the decrease would reach the level of 43%.


EU ETS annual cap for installations for the years 2013-2020 was as follows (source: Report from the Commission to the European Parliament and to the Council, Report on the functioning of the European carbon market, 23 November 2017 (COM(2017) 693 final, p. 11, Report on the functioning of the European carbon market, 18 November 2020, COM(2020) 740 final, p. 11):
 - 2013  - 2 084 301 856,
 - 2014  - 2 046 037 610,
 - 2015  - 2 007 773 364,
 - 2016  - 1 969 509 118,
 - 2017  - 1 931 244 873,
 - 2018  - 1 892 980 627,
 - 2019  - 1 854 716 381,
 - 2020  - 1 816 452 135.


Annual aviation allowances put into circulation:


 - 2013  - 32 455 296,
 - 2014  - 41 866 834,
 - 2015  - 50 669 024,
 - 2016  - 38 879 316,
 - 2017  - 38 711 651,
 - 2018  - 38 909 585,
 - 2019  - 38 946 562.


According to Article 1 of the Commission Decision (EU) 2020/1722 of 16 November 2020 on the Union-wide quantity of allowances to be issued under the EU Emissions Trading System for 2021, the Union-wide quantity of allowances referred to in Article 9 of Directive 2003/87/EC amounts to 1 571 583 007 for 2021.


From 1 January 2021, the EU ETS Directive applies to and in the UK in respect of the generation of electricity in Northern Ireland, on the basis the Protocol on Ireland/Northern Ireland.

As a result, only the emissions from electricity generation in Northern Ireland remain subject to the EU ETS and will be accounted for in the cap (applied from the base period 2008-12).

This will determine a reduction of the cap in proportion to the emissions from the United Kingdom that are no longer accounted for.

Improvements of the EU ETS in the third phase



A major revision of the EU ETS system was agreed in 2009, for the implementation in the third trading phase to run from 2013 until 2020.


The overall driver for the 2009 EU ETS reform was to streamline its operating rules through increased harmonisation of its pre-existing parts fragmented by national borders of the EU Member States.


This tendency has been expressed, in particular, in the following EU ETS features in the period 2013-2020:


- For the purposes of enhanced predictability and stability, a single, EU-wide cap has been imposed na the allowances' volume, the cap was decreasing by 1.74% annually (in line with the Linear Reduction Factor - LRF), and replaced the previous system of the EU Member States' national caps;


- Open, transparent, harmonised and non-discriminatory auctioning has replaced the free allocation as the default method for allocating emission allowances (the detailed rules are stipulated in the EU ETS Auctioning Regulation;


- The procedures for the free allocation of emission allowances have also been harmonised across the EU and ambitious EU-wide ex-ante performance benchmarks have been introduced (Benchmarking Decision);


- Regulation for monitoring and reporting and Regulation for verification of emission reports and accreditation and supervision of verifiers have been adopted and apply directly in all EU Member States;


- Stricter rules and conditions for the use of international carbon credits in the EU ETS with harmonised limits for their use by operators (for details see here);


- Central electronic Union Registry has replaced the emissions allowances registries run previously individually by the EU Member States. The Central Union Emissions Allowances Registry is governed by a Registry Regulation applying directly in all EU Member States.


Another reform under implementation is to change the emission allowances legal status into financial instruments and subject them (along with being already in scope derivative financial instruments or auctioned products based on them) to financial market supervisory system, mainly to the Markets in Financial Instruments Directive and Regulation under the MiFID II package and the Market Abuse Regulation


The European Commission in November 2012 proposed a short-term measure to postpone (back-load) auctioning of 900 million emission allowances until 2019 and 2020. The European Parliament and the Council agreed on the proposal in December 2013 and the implementation of back-loading started in March 2014 (more on the EU ETS allowances backloading read here).


Subsequently, in January 2014 a proposal to establish a Market Stability Reserve was presented (the legislative process has been finalised with the adoption of the Decision (EU) 2015/1814 of the European Parliament and of the Council of 6 October 2015 concerning the establishment and operation of a market stability reserve for the Union greenhouse gas emission trading scheme and amending Directive 2003/87/EC).


On 15 July 2015 the Commission presented a legislative proposal to revise the EU Emissions Trading System in line with the 2030 framework.



Coverage of activities, installations and aircraft operators



Greenhouse gases


In terms of greenhouse gases EU ETS scope was firstly defined in the Directive 2003/87/EC and has been amended by the Directive 2009/29/EC, including some new activities (such as production and processing of non-ferrous metals, some chemicals etc.) and new greenhouse gases (nitrous oxide (N2O) and perfluorocarbons (PFCs)).


The EU ETS currently covers carbon dioxide (CO2) emissions, nitrous oxide (N2O) emissions from all nitric, adipic, glyoxal and glyoxylic acid production and perfluorocarbons (PFC) emissions from aluminium production (see Annex I of the Directive which lists the categories of activities to which the ETS currently applies).


Stationary installations


As from the start of the phase 3 of the EU ETS (i.e. 1 January 2013), the sectors with stationary installations covered by the EU ETS are energy intensive industries, including power stations and other combustion plants, with ≥20MW thermal rated input (except hazardous or municipal waste installations), oil refineries, coke ovens, iron and steel, cement clinker, glass, lime, bricks, ceramics, pulp, paper and board, aluminium, petrochemicals, ammonia, nitric, adipic, glyoxal and glyoxylic acid production, CO2 capture, transport in pipelines and geological storage of CO2.


Even though participation in the EU ETS is mandatory, in some sectors only installations above a certain size are included.


Moreover, participating countries can exclude small installations from the system if measures are in place that will cut their emissions by an amount equivalent to the amount of emissions which would have been cut had the installations been included in the EU ETS.


Participating countries may also add more sectors and GHGs to the EU ETS.


The EU ETS covers about 11 000 power plants and manufacturing installations in all EU Member States, Iceland, Norway and Liechtenstein (Report on the functioning of the European carbon market, accompanying the document Report from the Commission to the European Parliament and to the Council, Climate action progress report, including the report on the functioning of the European carbon market and the report on the review of Directive 2009/31/EC on the geological storage of carbon dioxide of 18 November 2015 (COM(2015) 576 final), p. 5).




The aviation scope of the EU ETS was initially limited to flights within the EEA until 2016 and later extended to 2023.


The aviation activities within the initial scope of the EU ETS included all flights from or to an aerodrome situated in the territory of a Member State to which the Treaty applies, with some exceptions as listed in Annex I of the EU ETS Directive. 


However, in the light of the negotiations within ICAO looking to propose a global market based mechanism for reduction of aviation emissions, this scope has been temporarily reduced and only flights within the EEA are covered.


Further reading on EU ETS coverage of aviation, in particular in the light of the CORSIA measure.



Table: Key features of the EU ETS across trading phases



Key features 

 Phase 1



Phase 2



Phase 3


Geography   EU27  EU27 + Norway, Iceland, Liechtenstein


EU27 + Norway, Iceland, Liechtenstein

Croatia from 1.1.2013

(aviation from 1.1.2014)




Power stations and other 

combustion plants ≥20MW 

Oil refineries 

Coke ovens 

Iron and steel plants

Cement clinker 






Paper and board


Same as phase 1 plus Aviation (from 2012)

Same as phase 1 plus



 Aviation from 1.1.2014


Nitric, adipic and glyoxylic

acid production

CO2 capture,

transport in pipelines and geological storage of CO2




N2O emissions via opt-in


CO2, N2O, PFC from aluminium production

 Cap  2058 million tCO2    1859 million tCO2


2084 million tCO2 in 2013,

decreasing in a linear way by 38 million tCO2 per year


Eligible trading  units




Not eligible: Credits from forestry, and large hydropower projects. 




Not eligible: 

CERs and ERUs from forestry, HFC, N2O or large hydropower projects. 

Note: CERs from projects registered after 2012 must be  from Least Developed Countries



 Source of the Table: EU ETS Handbook, p. 18, 19




Tradable units



There were four types of tradable credits under the EU ETS:


- EU Allowances (EUAs),

- EU Aviation Allowances (EUAAs),

- Certified Emission Reduction (CERs),

- Emission Reduction Units (ERUs).


EUAs are most common units, EUAAs have been created specifically for the compliance of aircraft operators and initially (until 31 December 2020) were allowed to be surrendered only by aviation operators and, hence, enjoyed considerably smaller tradable demand.


Starting from phase 4 of the EU ETS - i.e. as from 1 January 2021- aviation allowances can be surrendered in order to meet the compliance obligations of both aviation operators and stationary installations.


International credits, such as the CER and ERU, are no longer eligible for use in phase 4 of the EU ETS.


Before 1 January 2021 CERs and ERUs, as the qualifying credits for emission reductions accomplished outside the European Union, were eligible, within certain limits, to be submitted for compliance under EU ETS (however, they needed to be translated into EUAs in order to count for compliance purposes).


CERs were obtained through the Clean Development Mechanism (CDM), which allowed emission reductions achieved in less developed country to be credited in a developed country.


ERUs were produced through the Joint Implementation (JI) mechanism, which promoted technology transfer between Kyoto Protocol Annex 1 countries.



Free allocation


Although in phase 3 of the EU ETS, auctioning was the default allocation method, a significant amount of allowances was been allocated for free to industrial installations (about 43% of the total quantity of available allowances was allocated for free, while the share of allowances to be auctioned by Member States amounted to some 57%).


This was to address the risk of carbon leakage - a situation where companies transfer production to third countries with laxer constraints on GHG emissions, which may lead to an increase in their total emissions.


In this regard he following principles applied:

  • electricity production was not eligible for free allowances;
  • free allowances to manufacturing industry were distributed according to EU-wide harmonised rules;
  • the free allocation was based on performance benchmarks to strengthen the incentives for GHG emission reductions and innovation and reward the most efficient installations;
  • an EU-wide New Entrants' Reserve (NER) for new industrial installations and installations significantly increasing capacity was established, equivalent to 5% of the total amount of allowances for phase 3.


The sectors and sub-sectors deemed to be exposed to a significant risk of carbon leakage are placed on a carbon leakage list (originally the list covered the period 2015-2019, the revised EU ETS Directive prolonged its validity until 31 December 2020).

In phase 3, as the demand for free allocation exceeded the amount available, the allocation for all installations under the EU ETS was reduced by the same percentage through the application of a "cross-sectoral correction factor (CSCF)".

In 2017, the original CSFC values were revised.



EU ETS carbon market



The EU ETS carbon market is dominated by derivatives - it is assessed around 85% of trade in allowances involves the use of derivatives: futures, forwards, options, which are subject to EU financial markets regulations.


In 2014, the EU ETS total volume traded was 8.33 billion tonnes of CO2 either as spot allowances or derivatives of allowances (total value of EUR 47 billion), where only around 900 million allowances were traded on the spot market (value of about EUR 5.2 billion).


EU ETS covers more than 11 000 power stations and industrial plants in 31 countries, around 2 000 intermediaries, traders, organisations and individuals voluntarily participate in the EU ETS.



EU ETS evolution in the context of the European Green Deal



The climate neutrality to reach the objectives of the Paris Agreement is the central element of the European Green Deal, as set out by:

  • the European Commission in Communications of 2018 (COM(2018)773 final) and December 2019 (COM(2019)640 final);
  • the European Council (European Council conclusions of 12 December 2019);
  • the European Parliament (resolution of 14 March 2019 on climate change and resolution of 28 November 2019 on the 2019 UNClimate Change Conference in Madrid, Spain (COP 25)).


In further communications (COM (2020)80 final and COM (2020) 562 final) the European Commission has proposed a EU-wide, economy-wide net greenhouse gas emissions reduction target by 2030 compared to 1990 of at least 55% and set the stage for this initiative together with other legislative initiatives in the field of climate and energy.


The Inception Impact Assessment of 29 October 2020 (Ref. Ares(2020)6081850) envisions the following potential modifications of the ETS Directive for 2021-2030 (phase 4):
- strengthening the EU ETS, while reviewing the Market Stability Reserve in line with the corresponding legal obligation and examine possible amendments to its design; and ensuring continued effective protection for the sectors exposed to significant risk of carbon leakage while incentivising the uptake of low carbon technologies:
- including at least intra-EU emissions of the maritime sector to ensure the sector contributes to the emission reductions needed, in accordance with EU’s international commitment to economy-wide action under the Paris Agreement, and deciding whether to include emissions from other sectors such as buildings and road transport into emissions trading at EU level and assessing if a transitionary system is needed;
- addressing the distributional effects of this transition, by reviewing, as appropriate, the low carbon funding mechanisms and solidarity aspects in the distribution of allowances.


Pursuant to the said document of 29 October 2020, a broad variety of options will be explored, including on:
- the linear reduction factor to meet the higher 2030 target of at least 55%, a one-off reduction of the cap that would put it closer to the actual emissions level, as well as the interaction with the Market Stability Reserve (MSR);
- the parameters for the operation of the MSR, including the predefined range triggering adjustments to annual auction volumes, as well as the percentage rate applied to the total number of allowances in circulation;
- the extension of emissions trading to maritime emissions, potentially emissions from buildings and road transport or all fossil fuels combustion and waste incineration, as well as the interactions with the existing regulatory and non-regulatory framework applicable to these sectors;
- improving support for low-carbon and carbon removal investment and innovation such as carbon contracts for difference e.g. through the existing Innovation Fund.
- the ETS’ contribution to addressing specific distributional and innovation;challenges related to the transition to climate neutrality and its impacts, including the use of auction revenues and the Modernisation and the Innovation Fund;
- carbon leakage provisions, such as free allocation rules and updating emission benchmarks, coherence with a potential carbon border adjustment mechanism, indirect cost compensation.


Commission Communication of 17 September 2020 “Stepping up Europe’s 2030 climate ambition Investing in a climate-neutral future for the benefit of our people” (COM/2020/562 final) reads:

„The Commission has assessed carefully the possibility of reinforcing and expanding emissions trading as a tool to achieve greenhouse gas emissions reductions at the EU level.

The Commission sees important benefits in expanding the use of emissions trading in the EU, to deliver in an economically efficient manner an increased climate ambition of 55% greenhouse gas emissions reductions. Emissions trading can achieve greenhouse gas emissions reductions cost‑effectively. Its resulting carbon price internalises the climate externalities and gives consumers incentives to reduce greenhouse gas emissions. It guarantees environmental integrity in the form of the emissions cap and provides a strong price signal that influences daily operational and strategic investment decisions. At the same time, emissions trading raises revenues that can be re-invested in the economy leading to better overall economic outcomes.

As already announced in the European Green Deal, a further expansion of the system could include emissions from road transport and buildings. Already now, the EU ETS directly or indirectly covers around 30% of buildings emissions from heating.
Covering all emissions of fossil fuel combustion and integrating them in the EU ETS would present important benefits in terms of effectiveness and administrative feasibility. The Commission therefore intends to pursue such an integrated approach and will look into incorporating it in its legal proposal by next year June.”




chronicle   Regulatory chronicle




14 July 2021

European Green Deal: Commission proposes transformation of EU economy and society to meet climate ambitions 


3 December 2020


Commission Implementing Decision (EU) 2020/1834 of 3 December 2020 on greenhouse gas emissions covered by Decision No 406/2009/EC of the European Parliament and of the Council for the year 2018 for each Member State


18 November 2020


Report on the functioning of the European carbon market, COM(2020) 740 final


17 November 2020

Start of phase 4 of the EU ETS in 2021: adoption of the cap and start of the auctions


16 November 2020


Commission Decision (EU) 2020/1722 of 16 November 2020 on the Union-wide quantity of allowances to be issued under the EU Emissions Trading System for 2021


29 October 2020


Inception Impact Assessment, EU ETS reform, Feedback period 29 October 2020 - 26 November 2020, Ref. Ares(2020)6081850


17 September 2020


Commission Communication Stepping up Europe’s 2030 climate ambition Investing in a climate-neutral future for the benefit of our people, COM/2020/562 final

31 October 2019

Commission Implementing Regulation (EU) 2019/1842 of 31 October 2019 laying down rules for the application of Directive 2003/87/EC of the European Parliament and of the Council as regards further arrangements for the adjustments to free allocation of emission allowances due to activity level changes

9 April 2019


Commission Staff Working Document, Progress in Accelerating Clean Energy Innovation 2018, SWD(2019) 157 final


17 December 2018


Report from the Commission to the European Parliament and to the Council on the functioning of the European carbon market, COM(2018) 842 final


23 November 2017


Report from the Commission to the European Parliament and to the Council, Report on the functioning of the European carbon market, (COM(2017) 693 final


18 November 2015


Report on the functioning of the European carbon market, accompanying the document Report from the Commission to the European Parliament and to the Council, Climate action progress report, including the report on the functioning of the European carbon market and the report on the review of Directive 2009/31/EC on the geological storage of carbon dioxide (COM(2015) 576 final






 IMG 0744   Documentation




EU ETS Handbook


An analysis of the fundamental price drivers of EU ETS carbon credits, Johan Obermayer 


The EU ETS phase IV reform: implications for system functioning and for the carbon price signal, The Oxford Institute for Energy Studies, September 2018 




 clip2   Links





European Commission's website on EU ETS


European Commission’s website on the EU ETS revision for the phase IV (2021-2030)