Corsia Aviation Parallel

CORSIA, the Carbon Offsetting and Reduction Scheme for International Aviation, is ICAO’s global market-based measure for international flights, cited as the closest sector parallel to a shipping carbon mechanism. It sets a baseline of 85% of 2019 CO2 emissions and requires airlines to offset growth above that line by buying eligible emission units. The first phase, 2024 to 2026, is voluntary for participating states; the scheme becomes broadly mandatory from 2027 and runs to 2035. As of January 2026, 130 states participate. CORSIA is an offsetting scheme rather than a fuel-intensity or trading regime, which shapes the debate over how the IMO should price marine emissions.