Canada’s Air Transat joins world’s greenest airlines in global emissions ranking

Canadian airline Air Transat has been ranked among the world’s most emissions-efficient major carriers, according to a global report released this month by aviation analytics firm Cirium.

The Montreal-based airline placed 15th in Cirium’s ranking of the top 20 airlines with the lowest flight emissions intensity and was the only Canadian carrier to make the list.

Air Transat, known primarily for its transatlantic leisure flights, has gradually modernized its fleet and adopted measures to improve efficiency, including route optimization and fuel-saving practices. The airline operates a mix of Airbus A330s and A321neos, aircraft known for their lower fuel burn compared to older models.


The global leader was Hungary’s Wizz Air with an emissions intensity of 53.9 grams of CO₂ per ASK, followed by the US-based Frontier Airlines (54.4 g) and Turkey’s Pegasus Airlines (57.1 g).

Cirium said it analyzed 100 of the world’s largest airlines, using granular operational data such as aircraft type, fuel burn, passenger load, and real flight tracking.

How is emission measured?

The report measured emissions intensity in grams of carbon dioxide (CO₂) per available seat kilometer (ASK), a standard aviation metric that reflects how much CO₂ is emitted per seat per kilometer flown. Air Transat recorded an emissions rate of 61.5 grams of CO₂ per ASK.

Cirium stated that the ranking accounted for factors such as aircraft fuel efficiency, seating density, and flight route optimization. “Under our methodology, carriers flying newer, fuel-efficient aircraft with higher-density configurations naturally perform better,” the report said.

The rankings were based on flight-by-flight emissions data for 2023, collected and analyzed using Cirium’s new EmeraldSky platform. The methodology was independently reviewed by the consulting firm PwC.

Aviation accounts for roughly 2–3 percent of global carbon emissions, and the industry is under increasing pressure to lower its environmental impact. Experts say such rankings are key to providing transparency for passengers and investors. Cirium’s full report provides a benchmark for emissions performance across the commercial airline industry and is intended to inform future policy, investment, and consumer choices.