Brussels has allocated 5.2 million carbon allowances worth about €430 million to 130 airlines for their use of sustainable aviation fuel in 2025, more than quadrupling the first year’s support.
The European Commission adopted the decision on 8 September and published the outcome a week later. Support for sustainable aviation fuel uptake in 2025 came to about 5.2 million EU Emissions Trading System allowances. Member state authorities calculated the entitlements for each commercial airline. In total, 130 operators received a share.
The scale of the jump is the striking part. Last year’s equivalent support ran to €100 million in allowances. So the 2025 figure is more than four times larger. Airlines also benefit from a second mechanism, because they surrender no allowances on flights flown with eligible fuels. That zero rating was worth a further €135 million. Together the two incentives came to roughly €565 million.
How the support system works
Brussels introduced the mechanism through the EU ETS Directive in 2023. Since 2024 it has drawn on a pot of 20 million allowances worth around €1.5 billion. The money covers all or part of the price gap between fossil kerosene and eligible sustainable fuel. Every airline is treated on the same terms.
Because the Commission publishes the support prices, operators can see what they will recover before they buy. Airlines must also give visibility to the support under Article 8 of Regulation (EU) 2025/723. In practice, therefore, the subsidy is meant to be visible rather than buried in an annual report.
What the fuel actually delivered
Airlines claimed over 530,000 tonnes of sustainable fuel in 2025. The volume consisted of biofuels and advanced biofuels. According to the Commission, that use avoided about 1.7 million tonnes of carbon dioxide.
Set against aviation’s total emissions, the abatement remains small. Still, the direction is what interests policymakers. On the allowance support alone, the cost works out at roughly €250 for every tonne of carbon avoided. That is a high price, and it reflects how far sustainable fuel still sits above kerosene.
A much bigger pot is on the table
In July the Commission proposed expanding the mechanism as part of its EU ETS review. The plan would reserve an additional 110 million allowances, drawn from wider application of the system to aviation emissions. On current values that support would be worth around €15 billion.
The proposal widens the purpose as well as the pot. Alongside fuels, it would back electrification and work on the warming aviation causes beyond carbon dioxide. Those effects are poorly priced today, so including them would widen the system’s scope considerably.
