UK civil aviation regulators are expecting airlines and other travel organisations to adopt guidance by April next year on providing consumers with standardised emissions information about flights.

The Civil Aviation Authority has published a guidance framework – following a consultation – intended to improve availability of comparable emissions data.

These guidelines, it says, aim to enable passengers to “make more-informed travel choices” by having environmental information at the point of booking.

“We expect that, by April 2027, organisations will have had sufficient time to adopt this guidance,” the authority states. It will be reviewing booking providers – including airlines and travel agents – after this date, to assess progress.

The guidance framework document contains several key principles, such as accessibility – the emissions information should not be buried in sub-pages from the booking site – and transparency, detailing the source and methodology used.

Data should also be consistent for the same flight across different booking platforms.

It adds that the information should also be “granular and tailored as possible” to reflect individual flight choices, taking account of the aircraft type and engine type, distance flown, seat class, load factor, and cargo.

“When specific data is unavailable, the most credible and scientifically-robust alternative data sources should be used,” it says.

While the authority says the consultation responses showed “broad agreement” on the importance of providing such environmental information – with standardisation a key priority – several airlines raised concerns over financial and technical obstacles.

“Developing the necessary infrastructure to collect, verify, and distribute environmental data would require substantial investment, particularly for smaller airlines and travel platforms,” the framework document says, outlining the airlines’ responses.

“For example, integrating emissions information into global distribution systems and booking platforms poses complex technological challenges.”

It adds that some responding airlines also pointed out that operational issues – such as last-minute aircraft changes – could render pre-published data inaccurate, interfering with the principle of having up-to-date information.

According to the document, the authority considers that ensuring data is updated at least once a year will ensure consumers have access to information that is as specific as possible to their flights.