Front Page: Traficom
Front Page: Traficom

CORSIA – Carbon Offsetting and Reduction Scheme for International Aviation

In the General Assembly of the International Civil Aviation Organization (ICAO) in 2016, the member states made the decision to implement the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA). The decision made aviation the first field with a global market-based emissions reduction system.

Carbon-neutral growth in air traffic from 2020 onwards as the goal

Air traffic causes approximately 2% of the carbon dioxide emissions in the world; the share of international air traffic is approximately 1.3%. However, due to the rapid growth of air traffic, the emissions will multiply unless more effective measures are taken to reduce them.

The aim of CORSIA is to ensure the carbon-neutral growth of international air traffic from 2020 onwards, meaning that as air traffic grows, the emissions should remain at the level of 2020. According to the goals of ICAO, the primary methods of achieving emission reductions are aircraft technology, sustainable alternative fuels as well as energy-efficient aviation and use of airspace. However, these measures will not be enough for the near future, and therefore a market-based compensation system is required.

The growth of emissions is offset by purchasing emission units

In CORSIA, aircraft operators offset the growth of emissions in international air traffic by purchasing CORSIA’s approved emission units, mainly originating from emission reduction projects in other fields, on the carbon market. The compensation obligation is calculated annually by comparing the emissions generated on the routes between CORSIA member states to the average of emissions in 2019. Further information on the obligations of aircraft operators can be found on the page on the monitoring, reporting and verification of emissions (External link).

Participating states

ICAO maintains a list (External link) of the states that have volunteered to participate in CORSIA from the start on its CORSIA website. Finland has volunteered to join together with the 44 member states of the European Civil Aviation Conference (ECAC).


In accordance with Commission Delegated Regulation (EU) 2019/1603, CORSIA is implemented in the European Union on the basis of the Emissions Trading Directive (2003/87/EC). The Finnish Transport and Communications Agency Traficom is responsible for implementing CORSIA in Finland.

Currently, the aim is to reduce emissions from internal flights in the European Economic Area with the help of the EU emissions trading system for aviation (External link). The decision on the potential harmonisation of CORSIA and the EU emissions trading system for aviation will be made in the EU by the end of 2023.