Singapore-based airline Scoot was named the world’s most emissions-efficient airline in Cirium’s 2025 EmeraldSky Annual Review. When calculating for most available seat kilometres (ASK), Qatar Airways, Ryanair and Turkish Airlines were recognised as the top three most efficient global airlines.
Cirium’s ranking is based on CO2 per available ASK across the world’s 100 largest airlines.
“Airline emissions performance comes down to decisions the air line can control—fleet choices, seat configuration and how aircraft are deployed on routes,” says Cirium ceo Jeremy Bowen. “The airlines at the top of these rankings have got these fundamentals right, and it shows. Better emissions efficiency and lower fuel bills go hand in hand.”
The report says Wizz Air, last year’s top performer, came in second with a fleet averaging under five years, similar to other top performers Scoot, TUI Airways, Air Europa and Frontier Airlines. Long-haul operators are using the strategy of fleet renewal, with Virgin Atlantic using newer wide body aircraft and higher-capacity configurations to deliver emissions performance on long-distance routes. They ranked seventh. See the full report HERE.
