IATA pushes common standard for airline emissions data

Airlines should adopt a globally consistent method for calculating and displaying flight emissions as travellers and corporate customers demand clearer carbon information, the International Air Transport Association has said.

The industry body is pressing carriers, booking platforms, travel agencies and regulators to use comparable operational data rather than competing calculation models that can produce sharply different estimates for the same journey. The absence of a common framework can leave passengers uncertain about which flight carries the lower environmental cost and can complicate corporate emissions reporting.

IATA’s preferred approach uses verified operational information supplied by airlines, including aircraft type, fuel consumption, passenger load, freight carried, route distance and cabin class. Its methodology also divides emissions between passengers and cargo, recognising that both contribute to the weight transported by an aircraft.

The association argues that broad adoption of a single methodology would allow travellers to compare flights on a like-for-like basis. It would also help companies measure emissions from business travel, set carbon budgets and assess progress against environmental targets without combining incompatible datasets.

Interest in flight-specific carbon information has risen as companies face tighter disclosure requirements and consumers question the environmental claims attached to travel products. Carbon figures are now displayed by several booking engines, airlines and corporate travel systems, but the estimates can vary because providers rely on different assumptions about fuel burn, seating configuration, occupancy and the treatment of premium cabins.

A business-class passenger is generally allocated a larger share of an aircraft’s emissions because the seat occupies more space and reduces the number of travellers who can be carried. Differences in the way calculators apply this factor can significantly alter the figure shown during booking.

IATA’s CO2 Connect system draws on fuel and operational information covering 75 aircraft types, representing almost 98% of the active global passenger fleet. Its broader traffic dataset covers 881 aircraft operators responsible for about 93% of worldwide air travel. More than 70 airlines contribute primary operational data to the platform.

The system is designed for integration into airline websites, booking engines, corporate reporting tools and travel-management platforms. It can also account for reductions associated with sustainable aviation fuel, provided the fuel’s environmental attributes and allocation are recorded through recognised procedures.

Supporters say operational data offers greater accuracy than generic models based mainly on route distance and average aircraft performance. Two flights between the same cities may produce different emissions because of aircraft age, engine efficiency, passenger numbers, cargo weight, routing, weather conditions and airport congestion.

Standardisation could also limit misleading environmental marketing. Regulators are scrutinising sustainability claims that imply a flight is “green”, “carbon neutral” or environmentally preferable without sufficiently clear evidence. Consistent calculations would not eliminate disputes over such descriptions, but they could provide a more transparent foundation for any comparison.

The European Union has moved towards its own Flight Emissions Label, which is intended to give passengers standardised information when searching for tickets. The voluntary scheme uses certified data and a common calculation process, with participating airlines able to display emissions estimates in a prescribed format. The regulation establishing the label was adopted in December 2024. ][2])

The initiative illustrates both the growing demand for transparency and the risk of regional fragmentation. Airlines operate across multiple jurisdictions and could face separate reporting systems covering passenger calculations, corporate disclosures, carbon markets, sustainable fuel and non-carbon climate effects.

International aviation is already subject to the Carbon Offsetting and Reduction Scheme for International Aviation, administered through the International Civil Aviation Organization. CORSIA requires participating operators to monitor and report emissions and offset part of the growth above its baseline. The first phase runs from 2024 to 2026, while requirements are scheduled to widen from 2027.

Passenger-level calculations serve a different purpose from CORSIA’s operator-level obligations, but both depend on credible measurement and verification. IATA wants governments and industry participants to avoid creating overlapping formulas that increase costs without improving environmental outcomes.

The debate is becoming more important as aviation pursues net-zero carbon emissions by 2050. Sustainable aviation fuel, newer aircraft, operational improvements and carbon removals form the main elements of the industry’s strategy, yet sustainable fuel still supplies only a small fraction of global jet-fuel demand.

Transparent data will also be needed to demonstrate whether fuel purchases produce genuine emissions reductions and to prevent the same environmental benefit from being claimed by more than one customer. Airlines, fuel producers, corporate buyers and booking platforms will have to agree how those reductions are recorded and transferred.