The International Civil Aviation Organisation hailed its Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) as a global, harmonised answer to aviation’s growing climate impact. Yet the reality is very different: patchy enforcement, limited coverage, and heavy reliance on problematic offsetting with carbon credits.
CORSIA was supposed to address emissions from international flights, including those to and from Europe. But it does not cover all carbon dioxide emissions. It only applies to emissions above a high baseline – leaving a massive portion of pollution untouched.
Even in a miracle scenario where, for example, both Belgium and the United States fully implement CORSIA with penalties for non-compliance, the scheme would cover just 20% of emissions from a Brussels-New York commercial flight by 2030.
By contrast, the EU Emissions Trading System already covers 100% of emissions from all passenger flights within the European Economic Area. It sets a real carbon price and is projected to generate around €7 billion annually by 2030 even under the current limited, intra-EEA scope. This revenue helps fund genuine climate solutions rather than unreliable carbon credits.
No enforcement, no CORSIA
In practice, even this 20% coverage under CORSIA seems unlikely. CORSIA’s design has another critical flaw: its rules only become binding once countries transpose them into national law. Without national penalties for non-compliance, there is simply no incentive for airlines to follow the rules.
The pilot phase began in 2021, while the first phase has been running since 2024. The ‘mandatory’ second phase is expected to begin in 2027, which is less than a year away. Yet there remains significant uncertainty about how participating countries will enforce the system. Some fuel buyers have recently suggested penalties could be as low as $20 per tonne of CO₂ in some countries, while also pointing to differences in reputational risks globally, further highlighting the fragmentation within CORSIA.
As far as we can ascertain from publicly available information, even in the EU, which already prices aviation pollution, only a couple of member states seem to have integrated CORSIA into domestic law.
A climate scheme without meaningful (if any) penalties is not binding. It is a voluntary gesture.
The EU ETS shows what harmonised enforcement looks like. Airlines that fail to surrender sufficient allowances must pay €100 per tonne of CO2 and still cover the missing emissions. On top of this, all of their names need to be made public. The penalties are harmonised across the EU, ensuring consistency.
Even with fines, still not fine
Stronger enforcement alone would not fix CORSIA’s structural problems, even if every participating country imposed fines today. The European Commission will assess CORSIA’s effectiveness by mid-2026 and can propose extending the EU ETS to all departing flights if the global scheme proves insufficient. Given CORSIA’s high baseline, reliance on problematic offsets, and lack of enforcement, the conclusion should be clear.
Extending the EU ETS to departing flights could generate up to €9 billion annually by 2030. That funding could accelerate zero-emission aircraft development and expand high-speed rail infrastructure. These are real solutions that cut emissions at source rather than shifting them on paper.
Europe cannot keep grounded its climate ambition while it awaits a patchy offsetting scheme. It must ensure that aviation is fully integrated into a harmonised, enforceable carbon-pricing framework that raises much-needed revenues to transform the sector and support other climate measures.
