Compare ETS
Use this function to compare the design elements and characteristics of up to three ETSs from around the world.
EU Emissions Trading System (EU ETS)
General Information
Operational since 2005, the European Union Emissions Trading System (EU ETS 1) is the oldest cap-and-trade system in force and the largest in terms of the trading volume and value. It remains a cornerstone instrument of the EU’s policy framework to combat climate change and reduce GHG emissions cost-effectively.
Until 2023, the EU ETS 1 covered emissions from electricity and heat generation plants, manufacturing installations in Europe, and aircraft operators flying between airports in the European Economic Area (EEA) and from the EEA to Switzerland and to the UK. In January 2024, it was extended to cover emissions from maritime transport and in aviation, emissions from most flights to and from the EU’s nine outermost regions as well as departing flights from these outermost regions to Switzerland and the UK. Overall, the EU ETS 1 covers around 35%* of the bloc’s total emissions, with coverage declining compared to the previous year as a result of significant emissions reduction in the power sector in 2023.
The EU ETS 1 is currently in its fourth trading phase (2021 to 2030). Every year, covered entities must surrender allowances for their emissions under the EU ETS 1. Auctioning is the main method of distributing allowances, with free allocation, based on benchmarks, used to address the risk of carbon leakage.
The EU ETS 1 was revised in 2023 in the context of the “European Green Deal” to align the system with the EU’s 2030 climate target of at least a 55% net emissions reduction compared to 1990 levels. The revision is now in force and included:
- an increased ambition and expanded scope of the EU ETS 1, to maritime transport, and introduced a new, separate emissions trading system for buildings, road transport and additional sectors** (EU ETS 2, to start in 2028) ***;
- a strengthened the Market Stability Reserve (MSR);
- an update to the EU ETS 1 regarding aviation;
- updated rules for monitoring and reporting of emissions from maritime transport;
- the creation of the Social Climate Fund (starting in 2026) to complement the new EU ETS 2; and
- the establishment of a Carbon Border Adjustment Mechanism (CBAM) to address the risk of carbon leakage from specific sectors under the EU ETS 1 (to gradually replace free allocation).
Since June 2023, EU Member States are obliged to use all relevant ETS revenue (or an equivalent financial value) to support climate action and energy transformation. By the end of 2025, the EU ETS has raised a cumulative total of EUR 265.7 billion (USD 297.1 billion) since its inception.
* Based on 2023 data. Preliminary data for 2024 suggest a further decrease to 33%.
** Mainly industry sectors not covered under the existing EU ETS.
*** See EU ETS 2 factsheet.
The EU ETS 1 in 2024 saw a 5.7% year-on-year reduction in emissions from stationary sources. This reduction was largely driven by the power sector, where renewable electricity production (primarily from wind and solar) increased substantially, coupled with the decrease in both coal and gas. With this development, emissions from installations at the start of 2025 were around 50% below 2005 levels and well on track to achieve the 2030 target of a 62% reduction. Emissions from aviation under the EU ETS 1 continued to increase in 2024, partially due to broader geographic coverage.
In 2025, the compliance obligation for maritime transport operators commenced. Shipping companies must surrender allowances equal to 40% of their verified 2024 CO2 emissions and 70% for 2025. From 2026 onwards, the scope of covered emissions in the sector expands to include CH4 and N2O.
In aviation, free emission allowances for operators were down to 50% in 2025 and are fully phased out as of 2026. In parallel, a per-tonne financial support for sustainable aviation fuels (SAF) was introduced to incentivise uptake while free allocations are phased out.
Since 2020, the EU ETS 1 is linked with the Swiss ETS. In May 2025, the EU and the UK announced their intention to link their respective ETSs. Subsequently, the EU Council granted the Commission a negotiating mandate, authorising it to start formal talks with the UK on an ETS linking agreement.
From 2026, the definitive stage of the EU’s CBAM starts. The mechanism is introduced gradually alongside the phase-out of free allowances in CBAM-covered sectors in the EU ETS 1. By September 30, 2027, EU importers will have to surrender CBAM certificates for 2.5% of the GHG emissions embedded in relevant goods imported in 2026.
Emissions & Targets
3,105.6 MtCO2e (2023)*
* National emissions for the EU-27 reported to the UNFCCC and to the EU in May 2025 under the “EU Governance Regulation”. )
By 2030: Reduce net emissions to at least 55% below 1990 GHG levels (“European Climate Law”)
By 2040: Reduce net emissions to 90% below 1990 GHG levels (European Climate Law, amended)*
By 2050: Net zero (European Climate Law)
* Includes a contribution of high-quality international credits under Article 6 of the Paris Agreement.
EUR 73.43 (USD 82.97) (average 2025 auction price)
EUR 74.35 (USD 84.01) (average secondary market price 2025)
Size & Phases
PHASE 1: Three years (2005 to 2007)
PHASE 2: Five years (2008 to 2012)
PHASE 3: Eight years (2013 to 2020)
PHASE 4: Ten years (2021 to 2030)
An absolute cap limits the total emissions allowed in the system and is fixed ex-ante. It is set to reduce covered sectors’ emissions by 62% compared to 2005 levels by 2030.
PHASE 1 and PHASE 2: The cap was calculated bottom-up, based on the aggregation of the national allocation plans of each Member State. Phase 1 started with a cap of 2,096 MtCO2e in 2005; Phase 2 with a cap of 2,049 MtCO2e in 2008.
PHASE 3:
Installations: A single EU-wide cap was calculated based on emissions monitoring and set at 2,084 MtCO2e in 2013. It was reduced annually by a linear factor of 1.74% (applied to the midpoint of 2008 to 2012 baseline emissions). This translated into a year-on-year reduction of around 38 million allowances and resulted in a cap of 1,816 MtCO2e in 2020.
Aviation: Included in the EU ETS 1 in 2012, with a cap calculated separately. Legally, the system covers all outgoing and incoming flights to the EEA. The 2012 cap for aviation amounted to 221 MtCO2e (95% of 2004 to 2006 emissions). In 2013, however, the EU temporarily limited ETS obligations to flights within the EEA to support the development of a global market-based measure to reduce aviation emissions by the International Civil Aviation Organization (ICAO). The number of aviation allowances put into circulation in 2013 to 2016 was reduced to 38 million allowances annually. This ‘stop-the-clock’ limited scope of the EU ETS for aviation was extended until the end of 2026.
PHASE 4:
From Phase 4, the linear reduction factor applies annually to the overall cap. The factor is set at 2.2% per year (of 2008 to 2012 baseline emissions) for the period 2021 to 2023, 4.3% for 2024 to 2027 and 4.4% from 2028. In addition, the cap is also reduced in two steps, by 90 million allowances in 2024 and 27 million allowances in 2026.
Installations: A single EU-wide cap reduced annually. Following the 2023 ETS revision, the cap in 2026 is determined to be 1,185 MtCO2e. From 2021, the UK was no longer part of the EU ETS 1 (except for electricity generators in Northern Ireland).
Maritime: The 2026 cap was increased by 2.4 million allowances to reflect the inclusion of CH4 and N2O emissions into the EU ETS 1 scope.
Aviation: The aviation cap in 2026 amounted to 24.9 MtCO2e.
From Phase 4, a Member State may cancel allowances from their auction share if they take additional policy measures that result in a closure of electricity generation capacity. The quantity of allowances cancelled shall not exceed the average verified emissions of the installation from five years preceding the closure.
The EU ETS 1 scope in terms of activities and GHGs is specified in Annex I and Annex II of the “ETS Directive”.
PHASE 1: Power stations and other combustion installations with >20 MW thermal rated input (except hazardous or municipal waste installations), industry (various thresholds) including oil refineries, coke ovens, and iron and steel plants, as well as production of cement, glass, lime, bricks, ceramics, pulp, paper, and cardboard.
PHASE 2: Several countries included NOx emissions from the production of nitric acid. The EU ETS 1 also expanded to include Iceland, Liechtenstein, and Norway.
Aviation: Emissions from international aviation were included in the EU ETS in 2012 (>10,000 tCO2/year for commercial aviation; >1,000 tCO2/year for non-commercial aviation since 2013). However, the EU temporarily limited the scope of the EU ETS 1 for aviation to flights within the EEA. Exemptions for operators with low emissions were introduced.
PHASE 3: Carbon capture and storage installations, production of petrochemicals, ammonia, nonferrous and ferrous metals, gypsum, aluminum, as well as nitric, adipic, and glyoxylic acid (various thresholds) were added to the scope.
Aviation: In 2017, the limited scope for aviation was extended until 2023 to support the development of a global measure for aviation emissions under ICAO. Under the “Linking Agreement” between the EU and Switzerland, from 2020, the EU ETS 1 covers emissions from outgoing flights to Switzerland.
PHASE 4: Amendments introduced in view of the UK’s departure from the EU and in the 2023 revision of the EU ETS 1.
Power and industry: The scope of ETS and benchmarks used for free allocation was broadened from 2024 to remove barriers for the deployment of new technologies such as green hydrogen or hydrogen-based steel.
Aviation: Under the “Trade and Cooperation Agreement” between the EU and the UK, the EU ETS 1 applies to emissions from flights departing from the EEA to the UK from 2021 (the UK ETS applies to flights departing to EEA airports).
Emissions from most flights to and from the EU’s nine outermost regions as well as from departing flights from these regions to Switzerland and the UK were added to the scope from 2024.
Maritime: From 2024, emissions from all large ships (of 5,000 gross tonnage and above) entering EU ports are covered by the EU ETS 1, regardless of the flag they fly, covering:
- 50% of emissions from voyages starting or ending outside the EU;
- 100% of emissions that occur between two EU ports and when ships are in EU ports.
Initially, the scope extension to maritime transport covers only CO2 emissions. From 2026, CH4 and N2O emissions will also be covered.
The obligation for maritime companies to surrender allowances for their emissions is being gradually phased in.
- 2025: for 40% of emissions reported in 2024;
- 2026: for 70% of emissions reported in 2025;
- 2027 onward: for 100% of emissions reported in 2026 and later years.
To ensure environmental integrity during the phase-in, Member States will cancel the number of allowances equivalent to the difference between the surrendered allowances and the verified emissions in 2024 and in 2025.
Point source
8,704 stationary installations, 393 aircraft operators, 3,313 shipping companies (2024)
Allowance Allocation & Revenue
Share of auctioned allowances 2021 to 2025: up to 57% of the cap
PHASE 1: Allocation was based on Member States’ national allocation plans. Allowances were allocated through grandparenting. Some Member States used auctioning and some used benchmark-based allocation.
PHASE 2:
Auctioning: Eight Member States (Germany, United Kingdom, the Netherlands, Austria, Ireland, Hungary, Czechia, and Lithuania) held auctions corresponding to ~3% of the total allowance allocation.
Free allocation: ~90% of allowances were allocated for free.
PHASE 3:
Auctioning: The main method of distributing allowances was via auction, accounting for up to 57% of the cap. Of the share of allowances to be auctioned, 88% were distributed to Member States based on verified 2005 or average 2005 to 2007 emissions; 10% were allocated among 16 lower-income Member States under the solidarity provision; and the remaining 2% were allocated between the Member States that had reduced their emissions by at least 20% compared to the applicable base year under the Kyoto Protocol.
Free allocation: A significant volume of allowances was allocated for free to address the risk of carbon leakage, based on sector-specific performance benchmarks. As the demand for free allowances exceeded the volume of allowances available, the free allocation of each installation was subject to a uniform cross-sectoral correction factor — which was revised in 2017.
Power: Auctioning, with an optional transitional free allocation for the modernisation and diversification of electricity generation in ten lower-income Member States. At the end of Phase 3, eligible Member States could decide to continue using this option in Phase 4, monetize remaining allowances, or transfer them to the Modernisation Fund, created under the EU ETS 1 in 2018.
Industry: Free allocation based on sector-specific performance benchmarks, which reflect an average emissions intensity per unit of product of the most efficient 10% of installations in each sector. The European Commission established 54 benchmarks in 2011, using 2007 and 2008 activity data and literature sources (when data was missing). Sectors deemed at risk of carbon leakage received free allocation at 100% of the relevant benchmark. Sub-sectors deemed not at risk of carbon leakage had free allocation reduced gradually from 80% of the respective benchmark in 2013 to 30% by 2020.
The carbon leakage risk was assessed against emissions intensity and trade exposure:
- direct and indirect cost increase >30%; or
- non-EU trade intensity >30%; or
- direct and indirect cost increase >5% and trade intensity >10%.
Cost intensity was determined by the formula:
[Carbon price × (direct emissions × auctioning factor + electricity consumption × electricity emission factor)]/ gross value added
Trade intensity was determined by the formula:
(imports + exports)/(imports + production)
New Entrants’ Reserve (NER): 5% of the cap for Phase 3 was set aside to assist new installations or to cover installations whose capacity significantly increased since their free allocation had been determined. 300 million allowances from the reserve were allocated to the NER300, a large-scale funding program for innovative low-carbon energy demonstration projects.
Aviation: 15% of allowances were auctioned and 82% were allocated to aircraft operators for free. The remaining 3% constituted a special reserve for new entrants and fast-growing airlines. The number of allowances put into circulation for the aviation sectors was reduced to reflect the temporary limitation of the scope of the EU ETS 1 to flights within the EEA.
PHASE 4:
Auctioning: The main method of distributing allowances remains auctioning, accounting for up to 57% of the cap. Of the share of allowances to be sold, 90% are distributed to Member States based on their share of verified emissions, with 10% distributed among the lower-income Member States under the solidarity provision.
Free allocation: A significant volume of allowances is allocated for free to address the risk of carbon leakage, based on sectors-specific performance benchmarks. Benchmark values are updated twice in Phase 4 to reflect technological progress in different sectors. In 2021, the European Commission updated benchmark values for the first time* and they applied for 2021 to 2025. The values are adjusted for technological progress on a yearly basis. An annual reduction rate is determined for each benchmark. For the steel sector, which faces high abatement costs and leakage risks, a fixed reduction rate applies.
The uniform cross-sectoral correction factor for the adjustment of free allocation is one for 2021 to 2025.
The Phase 4 cap includes a buffer of more than 450 million allowances, earmarked for auctioning, which can be made available if the initial free allocation volume is fully absorbed (thereby avoiding the need to apply the cross-sectoral correction factor).
In 2026, a second allocation period of the Phase 4 starts. Free allocation for 2026 to 2030 will become conditional on the implementation of energy efficiency measures (based on audits or energy management systems) and of carbon neutrality plans for the worst performing installations, in order to incentivize decarbonization.
Power: Auctioning, with an optional transitional free allocation for the modernization and diversification of electricity generation in ten lower-income Member States. Three of the eligible Member States decided to continue using this option in Phase 4, which could have been used until the end of 2024. After this time, any leftover allowances were added to a Member State’s share of allowances to be auctioned or its share of the Modernisation Fund.
Industry: Updated benchmark values that apply for 2021 to 2025 were calculated based on activity data for installations over 2016 to 2017, supplied by Member States. The updated values were compared to the original benchmarks to determine the reductions to be applied over the 15-year period between 2007/08 and 2022/23. Benchmarks could be reduced between 3% and 24% over this period. In total, 31 out of 54 benchmarks have been reduced by the maximum rate of 24%.
The update to the benchmarks for the period from 2026 to 2030 is based on increased annual reduction rates, which are intended to stimulate further industrial transformation. As of 2026, the minimum rate increases from 0.2% to 0.3% per year, and the maximum rate from 1.6% to 2.5%.
There are revised rules covering adjustments to free allocation when an installation makes a significant change to its production. These rules apply from Phase 4. The threshold for adjustments is a 15% increase or decrease in production. Adjustments to free allocation are issued based on yearly production data reports that operators submit to national competent authorities. Adjustments to the level of free allocation are made from the New Entrants’ Reserve.
Carbon leakage rules: The third carbon leakage list, adopted in February 2019, applies for 2021 to 2030. The list includes a reduced number of sectors classified at risk of carbon leakage. Free allocation for other sectors will be discontinued by 2030 (except for district heating).
Carbon leakage is assessed against a composite indicator of trade intensity and emissions intensity, according to the following criteria:
Trade intensity x emissions intensity > 0.2
Trade intensity x emissions intensity > 0.15 but < 0.2; qualitative assessment will follow based on abatement potential, market characteristics, and profit margins.
Emissions intensity is determined by:
[direct emissions + (electricity consumption x electricity emission factor)]/ gross value added
Trade exposure is determined by:
(imports + exports)/(imports + production)
Carbon Border Adjustment Mechanism: Free allocation to specific sectors will be gradually phased out from 2026 to 2034, in parallel to the phase-in of the EU’s CBAM for third-country imports. Those sectors are iron and steel, cement, aluminum, fertilizers and hydrogen. The mechanism applies equally to imports from all countries outside the EU (except Liechtenstein, Iceland, and Norway as they are participating in the EU ETS; and Switzerland which has an ETS that is linked with the EU ETS 1).
The transitional, data-collection phase of CBAM started in October 2023, with only reporting obligations but no charges due.
The phase-out of free allocation to sectors covered by the CBAM will take place by applying a ‘CBAM factor’, which will decrease gradually from 97.5% in 2026, to 51.5% in 2030 and down to 14% in 2033.
The CBAM will also apply to electricity imports.
New Entrants’ Reserve (NER): The initial volume of the NER at the start of Phase 4 amounted to 331.3 million allowances. This included unallocated allowances from Phase 3 and 200 million allowances from the MSR.
Aviation: Phase 3 breakdown applied until 2023. Free allocation to aviation will be phased out gradually – reduced to 75% in 2024, 50% in 2025 and to 0% from 2026 onward
* Revised benchmark values for free allocation of emission allowances for 2021 to 2025.
EUR 265.7 billion* (USD 297.1 billion) since the beginning of the system
EUR 43.2 billion** (USD 48.9 billion) in 2024
* Includes revenues from Iceland, Liechtenstein, Norway, and the UK (until 2020), as well as of the Innovation and Modernisation Funds funded by the EU ETS.
** Includes revenues from Iceland, Liechtenstein, Norway, and Northern Ireland, as well as of the Innovation and Modernisation Funds funded by the EU ETS.
Revenue from the auctioning of allowances under the EU ETS 1 accrues primarily to national budgets. As of June 2023, countries are required to use all ETS revenue (or an equivalent financial value) to support climate action and energy transformation.
EU Member States can also use their EU ETS 1 revenue as aid to certain electricity-intensive industries, to compensate for the additional electricity costs they face as a result of the carbon price pass through. They do so under State aid schemes that are approved by the European Commission. Every year, countries must publish the total compensation amounts paid out, including a breakdown by recipient sector and subsector. The overall spending under a scheme should not exceed 25% of collected EU ETS 1 revenue.
EU Member States report annually to the European Commission on how they used their auction revenue in a preceding year. Of the EUR 16.4 billion spent in 2024, Member States reported having supported projects in energy supply, grids and storage (20%), public transport and mobility (22%), social support and just transition (9%), energy efficiency, cooling and heating in buildings (20%), industry decarbonisation (5%), and road transport (3%) as well as other things (17%), that included international purposes and climate finance supporting climate action in vulnerable third countries.
A share of EU ETS 1 allowances is auctioned to supply the Innovation and Modernisation Funds, which were established to support decarbonization and modernization investments in ETS sectors.
Innovation Fund: One of the world’s largest funding programmes for rolling out low- and zero-carbon innovative solutions and technologies in energy, industry and net-zero mobility, funded entirely by the EU ETS 1. The fund provides grants for projects aimed at commercialising innovative low-carbon technologies and bringing industrial solutions to market to decarbonize Europe and support the transition to climate neutrality. It has an estimated budget of EUR 40 billion (USD 45.2 billion) until 2030 (dependent on the carbon price).
Modernisation Fund: A solidarity programme financed by the EU ETS 1. The fund supports lower-income Member States in financing projects that modernize energy systems, improve energy efficiency and help advance a socially just transition to climate neutrality. It has an estimated budget of EUR 56 billion (USD 63.3 billion) from 2021 to 2030 (allocated among the beneficiary Member States according to a fixed key).
Flexibility & Linking
Banking is allowed (since 2008).
Borrowing is not allowed.
PHASE 1: The use of CDM and Joint Implementation (JI) credits was allowed without limitation. In practice, no offset credits were used in Phase 1.
PHASE 2: The use of offset credits was allowed. 1,058 MtCO2e of international credits were used.
Qualitative limits: Most categories of CDM/JI credits were allowed, except for LULUCF and nuclear power. Strict requirements applied for large hydropower projects exceeding 20 MW.
Quantitative limits: In Phase 2, operators were allowed to use JI and CDM credits up to a certain percentage limit determined in the respective country’s National Allocation Plan. Unused entitlements were transferred to Phase 3.
PHASE 3: The use of offset credits was allowed with strict limitations.
Qualitative limits: Newly generated international credits (post-2012) had to originate from projects in least developed countries. Credits from CDM and JI projects from other countries were eligible only if registered and implemented before the end of 2012. Projects from industrial gas credits (projects involving the destruction of HFC-23 and N2O) were excluded regardless of the host country. Credits issued for emission reductions that occurred in the first commitment period of the Kyoto Protocol (2008 to 2012) were no longer accepted after March 2015.
Quantitative limits: The total use of credits for Phase 2 and Phase 3 was capped at 50% of the overall reduction under the EU ETS in that period (~1.6 GtCO2e).
PHASE 4:
The use of offset credits is not allowed.
The EU ETS 1 and the Swiss ETS have been linked since 2020. A direct link was created between the registries of both systems. It allows regulated entities to transfer allowances from an account in one system to an account in the other system. Allowances that can be used for compliance purposes in one system are recognised for compliance purposes of the other system.
In May 2025, the EU and the UK announced their intention to link their respective ETSs. Subsequently, the EU Council granted the Commission a negotiating mandate, authorising it to start formal discussions with the UK on a linking agreement.
Fuel ETS (national): in Austria and Germany, to be replaced by the EU ETS 2 [see ‘EU ETS 2 factsheet’]).
Carbon tax (national): in Denmark, Estonia, Finland, France, Hungary, Latvia, Netherlands, Norway, Poland, Slovenia, Spain, and Sweden.
Compliance
One calendar year.
FRAMEWORK: A harmonized framework of MRV and accreditation requirements underpins the EU ETS 1 functioning. Every year, Member States report on implementation of this framework:
- “Monitoring and Reporting Regulation (2018/2066)”
- “Accreditation and Verification Regulation (2018/2067)”
- “Monitoring and Reporting Regulation for maritime transport (2015/757)”
MONITORING: Each installation, aircraft operator and shipping company is required to have an emission monitoring plan, approved by a national competent authority.
REPORTING: Emission reports are submitted annually by the end of March for the preceding calendar year using templates.
Installations for the incineration of municipal waste (above a threshold of 20 MW rated thermal output) must monitor and report their emissions under the EU ETS 1 since January 1, 2024, with no surrender obligation.
VERIFICATION: Emission reports are verified by independent accredited verifiers before the end of March of the following year. Once verified, operators must surrender the equivalent number of allowances by the end of September. Verifiers must be accredited by national accreditation bodies of Member States in accordance with the Accreditation and Verification Regulation (EU) 2018/2067, which is based on the ISO/IEC 17029 and ISO 14065 international standards for GHG validation and verification bodies.
In addition, a dedicated MRV framework for non-CO2 aviation effects has started to apply from January 2025.
Regulated entities must pay an excess emissions penalty of EUR 100 (USD 113), adjusted for inflation with 2013 as the base year, for each tCO2e emitted for which no allowance has been surrendered, in addition to buying and surrendering the equivalent number of allowances. The name of the non-compliant operator is also made public. Member States may enforce different penalties for other forms of non-compliance.
Market Regulation
MARKET PARTICIPATION: Compliance entities and non-compliance entities.
MARKET TYPES:
Primary: Uniform price auctions with single rounds and sealed bids, conducted daily by EEX. Germany has opted out of the common auctioning platform, instead running national auctions through the EEX. Poland has also opted out but continues to participate on the common auction platform at the EEX until further notice.
Secondary: Spot, futures, options, and forward contracts are traded on the secondary markets, both on exchange and over the counter. Besides the EEX, futures are traded on ICE, ENDEX, and Nasdaq.
LEGAL STATUS OF ALLOWANCES:
Classified as financial instruments. The associated derivatives can hence be traded on secondary markets.
MARKET STABILITY RESERVE (MSR)
Instrument type: Quantity-based instrument
Functioning: The MSR was created in 2015 as a long-term measure to address a growing surplus of allowances in the EU ETS 1. It adjusts auction volumes according to pre-defined thresholds of the total number of allowances in circulation (TNAC), fostering balance in the EU carbon market and resilience to demand shocks. The MSR started operating in 2019.
Triggers: The Commission publishes the TNAC communication every year.
- If the TNAC is above 1,096 million, 24% of its volume is withdrawn from future auctions and placed into the MSR over a period of 12 months.
- If the TNAC is between 833 million and 1,096 million, to mitigate threshold effects, a smaller share of allowances is deducted from auction volumes and placed in the MSR.
- If the TNAC is less than 400 million, 100 million allowances are released from the MSR and auctioned.
Invalidation: From 2023, allowances in the MSR above a certain threshold are invalidated annually. In 2023, the applicable threshold was the 2022 auction volume. From 2024 onward, the applicable threshold is fixed at 400 million allowances.
Other Information
European Commission: Responsible for establishing the regulatory framework of the EU ETS 1 and centralized administration of the system, e.g., the EU registry.
Competent authorities of all EU Member States as well as Iceland, Liechtenstein, and Norway: implementation, e.g., verifying compliance with MRV and surrender obligations.
The European Commission publishes annual reports on the functioning of the European carbon market.*
The ETS Directive stipulates that the system is kept under review in light of the implementation of the Paris Agreement and the development of carbon markets in other major economies. Three major EU ETS 1 reviews — before Phase 3, before Phase 4, and in the context of increasing the EU 2030 climate target — have been conducted to date.
By the end of July 2026, the European Commission will assess:
- how negative emissions (removals) could be accounted for and covered under the EU ETS 1;
- the feasibility of lowering the 20 MW total rated thermal input thresholds for the activities covered under the EU ETS 1;
- effective accounting and avoidance of double counting of CCU products under the EU ETS 1;
- the feasibility of including municipal waste incineration under the EU ETS 1; and
- the functioning of the EU ETS 1 for aviation, including the functioning of CORSIA.
* The latest report was published in 2025, on the EU ETS functioning in 2024.
All other legislation and documentation can be found here.
USA - California Cap-and-Trade Program
General Information
The California Cap-and-Invest Program began operation in 2012 with the opening of its tracking system for allocation, auction distribution, and trading of compliance instruments. Compliance obligations started in January 2013. The program was extended through 2045 and renamed Cap-and-Invest by legislation adopted in 2025. The program puts a carbon price on ~76% of the state’s GHG emissions.
The program covers fuel combustion emissions in the mining, power, buildings, transport, industrial, agriculture, and forestry sectors, as well as industrial process emissions of about 400 covered facilities. Fuel use in buildings, transportation, and in agricultural, forestry, and fishing operations is covered upstream at the fuel supplier. Covered entities must surrender allowances for all their covered emissions. Allowances are distributed via a combination of auction, free allocation, and free allocation with consignment. The proceeds from auctioning are reinvested in projects that reduce emissions, strengthening the economy, public health, and the environment, especially in disadvantaged communities.
The California Cap-and-Invest Program is implemented under the authority of the California Air Resources Board (CARB). California has been part of the Western Climate Initiative (WCI) since 2007 and formally linked its program with Québec’s in January 2014.
In September 2025, California adopted Assembly Bill 1207 (AB 1207) and Senate Bill 840 (SB 840), which extended the Cap-and-Invest Program (formerly Cap-and-Trade) through 2045 and made technical changes to the Program.
AB 1207 directs CARB to ensure that program-wide aggregate emissions from covered sources decline, at a minimum, in line with the state’s 2030 and 2045 climate targets, maintain robust price-containment mechanisms, set offset usage limits for 2031 to 2045, and remove allowances from future budgets equal to offsets used for compliance, while considering cost-effectiveness and affordability, minimizing leakage risks, and avoiding disproportionate impacts on low-income communities. SB 840 complements these changes by requiring CARB to conduct an evaluation of the Compliance Offsets Program by the end of 2026 and to update all existing compliance offset protocols to reflect the best available science by January 1, 2029.
By 2034 and every five years thereafter, SB 840 further requires CARB to evaluate all compliance offset protocols and consider whether updates are necessary to reflect the best available science. SB 840 also sets future appropriation rules for Greenhouse Gas Reduction Fund programs, including affordable housing, sustainable communities, community air monitoring, and high-speed rail.
In January 2026, CARB proposed changes to the Cap-and-Invest Regulation to implement the requirements of AB 1207. The formal rulemaking process is underway with regulatory amendments expected to be adopted and reflected in allowance budgets from 2027 onwards.
California and Québec continue to operate a joint carbon market, while California, Québec, and Washington continue discussions about potential future linkage of Washington’s program to the joint market.
Emissions & Targets
360.4 MtCO2e (2023)
By 2030: 40% reduction from 1990 GHG levels (“SB 32”)
By 2045: Carbon neutrality and 85% reduction from 1990 anthropogenic GHG levels (“AB 1279”)
Updated prices available here
- Average Current Auction price: USD 28.14* (2025)
- Average secondary market price: USD 29.10 (2025)
* “Current auction settlement price“ in USD, weighted by the total number of government-owned and consignment current vintage allowances sold in the year for both California and Québec.
Size & Phases
FIRST COMPLIANCE PERIOD: Two years (2013 to 2014)
SECOND COMPLIANCE PERIOD: Three years (2015 to 2017)
THIRD COMPLIANCE PERIOD: Three years (2018 to 2020)
FOURTH COMPLIANCE PERIOD: Three years (2021 to 2023)
FIFTH COMPLIANCE PERIOD: Three years (2024 to 2026)
SIXTH COMPLIANCE PERIOD: Three years (2027 to 2029)
An absolute cap limits the total emissions allowed in the system and is fixed ex-ante.
FIRST COMPLIANCE PERIOD: The system started in 2013 with a cap of 162.8 MtCO2e, declining to 159.7 MtCO2e in 2014, at a rate of ~2% annually.
SECOND COMPLIANCE PERIOD: With the program expanding to include fuel distribution, the cap rose to 394.5 MtCO2e in 2015. The cap decline factor averaged 3.1% per year in the second compliance period, reaching 370.4 MtCO2e.
THIRD COMPLIANCE PERIOD: The cap in the third compliance period started at 358.3 MtCO2e and declined at an average annual rate of 3.3% to 334.2 MtCO2e in 2020.
FOURTH COMPLIANCE PERIOD AND BEYOND: During the 2021 to 2030 period, the cap declines by about 13.4 MtCO2e each year, averaging ~4%, to reach 200.5 MtCO2e in 2030. The “Cap-and-Invest Regulation” (the Regulation) sets a formula for declining caps after 2030 through 2050.
Rulemaking is underway to implement recent legislative requirements and to align allowance budgets with California’s 2030 and 2045 targets.
FIRST COMPLIANCE PERIOD: Covered sectors included those that have one or more of the following processes or operations: large industrial facilities (including cement, glass, hydrogen, iron and steel, lead, lime manufacturing, nitric acid, petroleum and natural gas systems, petroleum refining, and pulp and paper manufacturing, including cogeneration facilities co-owned/operated at any of these facilities); electricity generation; electricity imports; other stationary combustion; and CO2 suppliers.
SECOND COMPLIANCE PERIOD AND BEYOND: In addition to the sectors listed above, suppliers of natural gas, suppliers of reformulatedblendstock for oxygenateblending (i.e., gasoline blendstock) and distillate fuel oil (i.e., diesel fuel), suppliers of liquefied petroleum gas in California, and suppliers of liquefied natural gas are covered by the program.
INCLUSION THRESHOLDS: Facilities emitting greater than or equal to 25,000 tCO2e per year. All electricity imported from specified sources connected to a specific generator with emissions greater than or equal to 25,000 tCO2e per year is covered. Emissions associated with imported electricity from unspecified sources have a zero threshold, and all imported electricity emissions are covered using a default emissions factor.
OPT-IN COVERED ENTITIES: A facility in one of the covered sectors that emits less than 25,000 tCO2e annually can voluntarily participate in the Program. Opt-in entities are subject to all registration, reporting, verification, compliance obligations, and enforcement applicable to covered entities.
Upstream (buildings, transport, agriculture, and forestry fuel use); point source (mining and extractives, industry, in-state power generation); imported electricity at the point of first delivery onto California’s electricity grid
~400 facilities (2025)
Allowance Allocation & Revenue
Proportion of 2025 cap auctioned as 2025 vintage units: 42.8%*
Allowances are distributed via free allocation, free allocation with consignment, and auction.
FREE ALLOCATION: Industrial facilities receive free allowances to minimize carbon leakage. For nearly all industrial facilities, the amount is determined by product-specific benchmarks, recent production volumes, a cap adjustment factor, and an assistance factor based on assessment of leakage risk. **
Leakage risk is divided into “low”, “medium”, and “high” risk tiers based on levels of emissions intensity and trade exposure for each specific industrial sector.
FIRST COMPLIANCE PERIOD: The Regulation as adopted in 2011 set assistance factors of 100% for the first compliance period, regardless of leakage risk.
SECOND COMPLIANCE PERIOD AND BEYOND: For facilities with medium leakage risk, the original regulation included an assistance factor decline to 75% for the second compliance period and to 50% for the third. For facilities with low leakage risk, it included an assistance factor decline to 50% for the second compliance period and to 30% for the third. However, amendments to the Regulation in 2013 delayed these assistance factor declines by one compliance period. Pursuant to “AB 398” adopted in 2017, all assistance factors were changed to 100% through 2030, citing continued vulnerability to carbon leakage. There is no cap on the total amount of industrial allocation, but the formula for allocation includes a declining cap adjustment factor to gradually reduce allocation in line with the overall cap trajectory.
Free allocation is also provided for transition assistance to public wholesale water entities, legacy contract generators, universities, public service facilities, and, during the period from 2018 to 2024, waste-to-energy facilities.
FREE ALLOCATION WITH CONSIGNMENT: Electrical distribution utilities and natural gas suppliers receive free allocation on behalf of their ratepayers.*** These utilities must use the allowance value for ratepayer benefit and for GHG emissions reductions. All allowances allocated to investor-owned electric utilities and an annually increasing percentage of the allocation to natural gas suppliers must be consigned for sale at the state’s regular quarterly auctions. Publicly owned electric utilities can choose to consign freely allocated allowances to auction or use them for their own compliance needs.
AUCTIONING:
- Auction share: ~67% of total California-issued vintage 2025 allowances made available through auction in 2025, which included allowances owned by CARB (~35%) and allowances consigned to auction by utilities (~32%).
- Auction volume: 174,505,948 (2025 vintage); 22,730,000 (2028 vintage).
- Share of the 2025 cap auctioned as vintage 2025 CARB-owned allowances so far: 42.8%.
Unsold allowances in past auctions are gradually released for sale at auction after two consecutive auctions are held in which the clearing price is higher than the minimum price. However, if any of these allowances remain unsold after 24 months, they will be placed into CARB’s price ceiling reserve or into the two lower reserve tiers (see ‘Market Stability Provisions’ section). To date, 37 million allowances originally designated for auction have been placed in reserves through these provisions.
* Excluding consigned allowances.
** See Section 95891(c) of the Regulation for a minor exception.
*** See Section 95892 and Section 95893 of the Regulation for further details on the approach to free allocations for electrical distribution utilities and natural gas suppliers, respectively.
USD 34.5 billion since beginning of program
USD 3.13 billion* in 2025
* Does not include revenues from the auction of consigned allowances.
Revenue from auction of California-owned allowances: Most of California’s auction revenue goes to the Greenhouse Gas Reduction Fund, of which at least 35% must benefit disadvantaged and low-income communities. The funds are then distributed as California Climate Investments, which support projects that deliver significant environmental, economic, and public health benefits across the state. As of November 2024, USD 12.8 billion had been invested in 590,703 projects, with expected GHG reductions of 116.1 MtCO2e.
Over USD 9.2 billion has reached disadvantaged and low-income communities.
Revenue from auction of utility-owned allowances: Investor-owned electric utilities and natural gas suppliers are allocated allowances, a portion of which must be consigned to auction. Auction proceeds must be used for ratepayer benefit and for GHG emissions reductions. Since the Program’s inception, approximately USD 26.5 billion in allowance value has been provided to ratepayers. Investor-owned electric utilities and natural gas suppliers have provided USD 13.5 billion directly to residential ratepayers through 2024 via the California Climate Credit.
Flexibility & Linking
Banking is allowed but is subject to a holding limit on allowances to which all entities in the system are held. The holding limit is based on the year’s cap and decreases annually. Entities may also be eligible for a limited exemption from the holding limit based on their emissions levels to support meeting annual compliance obligations or obligations at the end of a three-year compliance period.
Borrowing is not allowed.
The use of compliance offset credits is allowed. Such credits, issued by CARB or by the authority of a linked system, are compliance instruments under the California Cap-and-Invest Program.
QUALITATIVE LIMIT: Currently, offset credits originating from projects carried out according to one of the following six compliance offset protocols are accepted as compliance instruments:
- US forest projects;
- urban forest projects;
- livestock projects (methane management);
- ozone-depleting substances projects;
- mine methane capture projects; and
- rice cultivation projects.
Compliance offset credits issued by jurisdictions linked with California (i.e., Québec) are eligible, subject to the quantitative limits described below.
To ensure environmental integrity, California’s compliance offset program has incorporated the principle of buyer liability. The state may invalidate an offset credit that is later determined not to have met the requirements of its compliance offset protocol due to double counting, over-issuance, or regulatory non-conformance. The entity that surrendered the offset credit for compliance must then substitute a valid compliance instrument for the invalidated offset credit.
QUANTITATIVE LIMIT: The share of offsets that can be used by an entity to fulfill its compliance obligation is 4% per year for 2021 to 2025 emissions, and 6% for 2026 to 2045 emissions.
In addition to setting new quantitative limits on the use of offset credits, AB 398 set new limits on the types of offset credits that can be used to fulfill compliance obligations. Starting with compliance obligations for 2021 emissions, no more than 50% of any entity’s offset usage limit can come from offset projects that do not provide direct environmental benefits to the state (DEBS).
Projects located within California are automatically considered to provide DEBS. Offset projects implemented outside of California may still result in DEBS, based on scientific evidence and project data provided. For example, a forest project outside California has been determined to provide benefits within California by improving the quality of water flowing through the state. Recent regulatory amendments specify the criteria used to determine DEBS.
In November 2022, California entities surrendered ~2.2 million offset credits for a portion of 2021 emissions. In November 2023, California entities surrendered ~2 million offset credits for a portion of 2022 emissions.
In November 2024, California entities surrendered an additional 22 million credits for the remainder of their emissions during the fourth compliance period, while Québec entities surrendered 13.3 million California-issued offset credits. Of the 35.2 million credits surrendered, 26.5 million were from US forest offset projects and 5.3 million from mine methane capture projects.
In November 2025, California entities surrendered ~2.2 million offset credits at the annual compliance event for the first year of the fifth compliance period (2024), when compliance for 30% of the 2024 annual emissions was required.
California’s program linked with Québec’s in January 2014. The two expanded their joint market by linking with Ontario in January 2018 until the termination of Ontario’s system in mid-2018. In March and September 2024, joint statements from the governments of Québec, California, and Washington affirmed their commitment to explore potential linkage.
Compliance
Except for the year following the last year of a compliance period, compliance instruments equal to 30% of the previous year’s verified emissions must be surrendered annually, by the start of November. Compliance instruments equal to all remaining emissions must be surrendered by the start of November of the year following the last year of a compliance period.
FRAMEWORK: California’s MRV framework is set by the “Regulation for the Mandatory Reporting of Greenhouse Gas Emissions (MRR), title 17 California Code of Regulations (CCR) §§ 95100-95163”. The “Cap‑and‑Invest Regulation, title 17 CCR §§ 95801-96022” relies on MRR data.
MONITORING: Reporters must use calculation, monitoring, QA/QC, missing data, recordkeeping, and reporting methods specified in MRR.
MRR requires that reporters subject to the regulation maintain a GHG Monitoring Plan for facilities and suppliers that includes detailed, source‑specific monitoring and QA/QC obligations and record retention for all data used to calculate emissions, specified in MRR § 95105(c). Similarly, electric power entities that import or export electricity must maintain a GHG inventory program, as specified in MRR § 95105(d).
REPORTING: Annual reporting for the following entities based on emissions thresholds listed, using the standardized methods and formats specified in MRR:
- Facilities in specified categories (e.g., large power plants under 40 CFR Part 75, cement, lime, nitric acid, refineries, CO₂ sequestration/injection) report regardless of emissions level.
- Other facilities (e.g., stationary combustion, glass, hydrogen, iron and steel, pulp and paper, petroleum and natural gas systems, geothermal, lead) report at ≥10,000 tCO₂e/year of stationary and process emissions; petroleum and natural gas systems also apply a 25,000 tCO₂e threshold when including vented and fugitive emissions.
- Fuel and CO₂ suppliers report at ≥10,000 tCO₂e/year, calculated as volume of CO2 supplied, or based on emissions that would result from combustion of the fuels supplied
- Importers or exporters of electricity as defined in § 95102(a) with any volume of imported or exported electricity, retail providers as defined in § 95102(a), along with certain public agencies specified in § 95101(d)
VERIFICATION: Third‑party verification is required under MRR for emissions data reports of entities with a compliance obligation under the Cap‑and‑Invest Regulation and for other reporters above specified thresholds or categories, as specified in § 95103(f).
Verification requirements, including requirements for the accreditation of verification bodies and individual verifiers are specified in §§ 95130-95133. Similar accreditation and conflict‑of‑interest provisions apply to offset verifiers and verification bodies under Cap‑and‑Invest Regulation §§ 95977–95978.
Entities remain subject to annual reporting (and, where applicable, verification) under MRR until they meet the cessation conditions in § 95101(h)-(i).
A covered entity that fails to surrender sufficient compliance instruments to cover its verified GHG emissions at a relevant compliance deadline is automatically assessed an untimely surrender obligation. It is required to surrender the missing compliance instruments as well as three additional ones for each it failed to surrender.
Failure to meet this untimely surrender obligation would subject the entity to substantial financial penalties for its noncompliance, pursuant to “California Health and Safety Code Section 38580”.
Separate and substantial penalties apply to mis-reporting or non-reporting under the MRR.
Market Regulation
MARKET PARTICIPATION: Covered entities, opt-in covered entities, and voluntarily associated entities can participate in the program. Voluntarily associated entities are approved individuals or entities that intend to:
- purchase, hold, sell, or retire compliance instruments but are not covered under the program;
- operate a compliance offset project registered with CARB; or
- provide clearing services and derivative clearing services as qualified entities.
Voluntarily associated entities must be in the United States and have an approved account in the system registry, the Compliance Instrument Tracking System Service (CITSS). Additional eligibility criteria apply, including for individual market participants.
MARKET TYPES:
Primary: Allowances are made available through sealed-bid auctions. State-owned and consigned allowances are offered through quarterly allowance auctions organized jointly with Québec. Auctions are administered by WCI, Inc.
Secondary: Allowances, offset credits, and financial derivatives are traded in the secondary market on the Intercontinental Exchange (ICE), CME Group, and Nodal Exchange platforms. Any company qualified to access these platforms can trade directly or through a future commission merchant. Companies can also trade directly over the counter but must have a CITSS account to take delivery of compliance instruments.
LEGAL STATUS OF ALLOWANCES: Allowances are defined as limited tradable authorizations to emit up to one tCO2e. According to the “California Code of Regulations”, an allowance does not constitute property or bestow property rights and cannot limit the authority of the regulator to terminate or limit such authorization to emit.
AUCTION RESERVE PRICE
Instrument type: Price-based instrument
Functioning: The auction reserve price is set at USD 27.94 and CAD 26.47 per allowance in 2026.
It was initially established at USD 10.00 for the auction in 2012, and it increases annually by 5% plus inflation, as measured by the Consumer Price Index. The auction reserve price for each joint auction with Québec is determined using the minimum prices set annually by California in USD in accordance with Section 95911 of the Regulation and by Québec in CAD in accordance with Article 49 of the “Regulation respecting a cap-and-trade system for greenhouse gas emission allowances” (Québec Regulation). To manage multiple currencies, an Auction Exchange Rate is determined prior to each joint auction. The Auction Reserve Price for a joint auction is then determined as the higher of the Annual Auction Reserve Prices established in USD and CAD after applying the established Auction Exchange Rate (USD to CAD FX Rate).
ALLOWANCE PRICE CONTAINMENT RESERVE (APCR)
Instrument type: Price-based instrument
Functioning: In 2026, the two APCR tiers are set at USD 65.31 and USD 83.92 per allowance. Tier prices increase each year by 5% plus inflation, as measured by the Consumer Price Index.
At the start of the program, about 4.9% of allowances from the 2013 to 2020 budgets were placed in an APCR. Prior to amendments mandated by AB 398 in 2017, these allowances were spread across three tiers. Pursuant to AB 398, from 2021 onward, these allowances have been moved into two price tiers and a price ceiling. Currently, there are approximately 66.8 million and 89.5 million allowances in the Tier 1 and 2 reserves, respectively.
Although no APCR sale has been held so far, CARB will offer one if auction settlement prices from the preceding quarter are greater than or equal to 60% of the lowest APCR price tier. CARB also always offers the third quarter APCR sale before the November compliance obligation deadline.
ALLOWANCE PRICE CEILING
Instrument type: Price-based instrument
Functioning: In 2026, the price ceiling is set at USD 102.52. The price ceiling increases each year by 5% plus inflation, as measured by the Consumer Price Index.
At the price ceiling, a covered entity can purchase allowances (or, if no allowances remain, “price ceiling units”) up to the amount of its current unfulfilled emissions obligation. The revenues from the sale of price ceiling units will be used to purchase real, permanent, quantifiable, verifiable, enforceable, and additional emissions reductions on at least a tonne for tonne basis. Sales at the price ceiling will only be conducted if no allowances remain at the two lower APCR tiers and a covered entity has demonstrated that it does not have sufficient compliance instruments in its accounts for that year’s compliance event. Currently, there are approximately 77.7 million allowances in the Price Ceiling Account.
Other Information
California Air Resources Board: Responsible for the design and implementation of the Cap-and-Invest Program.
Western Climate Initiative, Inc.: Non-profit organization that provides cost-effective administrative and technical solutions for supporting the coordinated development and implementation of participating jurisdictions’ GHG emissions trading programs, such as administering auctions and maintaining the system registry (CITSS).
Pursuant to requirements in existing legislation (AB 32, AB 197, and AB 398), CARB must update the “California Climate Change Scoping Plan” at least every five years and must provide annual reports to various committees of the Legislature and the Board. The Scoping Plan provides updates on progress toward climate targets and lays out strategies to achieve them, including the role and level of effort accorded to different programs in the state’s portfolio approach to climate mitigation. The latest update to the Scoping Plan was adopted in December 2022.
Global Warming Solutions Act of 2006 (AB 32)
Current Cap-and-Invest regulation can be found on the dedicated CARB website.
Current MRV regulation can be found on the dedicated CARB website.