UK a “hotspot” for aviation pollution, new study shows

Almost one million flights departed from UK airports last year, releasing 34.1 million tonnes (Mt) of CO₂— this equates to 91% of 2019 flight numbers and 95% of emissions that year. Six out of ten of Europe’s most polluting routes departed from the UK capital, with London-New York topping the list (1.4 Mt of CO₂ for departing flights.) The majority of these emissions were not priced under the UK carbon market (UK ETS), which only applies to domestic flights and those to the European Economic Area (EEA) and Switzerland. This is a major flaw in the design of the legislation and allowed airlines to dodge paying for 83% [1] of their emissions last year.

Extending the UK’s carbon market to cover extra-European flights would help fix this imbalance and unlock vital revenues. T&E estimates that an extension of the UK ETS to flights outside of Europe could have generated an additional £1 billion in 2024 if extra-European emissions were priced [2]. Part of these revenues could help the UK to kickstart its domestic sustainable aviation fuels (SAF) industry.

Anna Krajinska, Director of T&E UK said: “Airlines are fast-approaching pre-COVID levels of pollution, and they’re using London as their launchpad. But the UK government isn’t holding them accountable – our carbon pricing is failing to catch 83% of airline emissions, and we are giving the go-ahead to even more pollution with the planned expansions of Luton and Heathrow. We need to put an end to airport expansion and extend the scope of the UK’s carbon market to ensure airlines pay the true cost of their pollution and raise badly needed revenue for the exchequer.”

Looking at Europe overall Ryanair was the most polluting airline. Just ten airlines were responsible for 40% of all European aviation emissions.

For flights departing the UK, British Airways was the top polluting airline, emitting 7.8 Mt of CO₂ last year. Other top polluting UK airlines included easyJet and Virgin Atlantic Airways. Jet2 was the fastest growing airline, increasing their traffic by 14% in 2024 compared to 2023.

T&E’s analysis shows that the majority of airline emissions (83%) from extra-European flights were unpriced under the UK ETS last year.

Moreover, UK climate policies have fallen behind the EU, as they do not integrate aviation’s non-CO₂ climate impact into their scope [3] – which is at least as important as the climate impact of aviation's CO₂ emissions. Additionally, whereas the EU is cracking down on airport expansion, the UK government has given the go-ahead to further air traffic and pollution by approving the expansions of Heathrow and Luton airports. 

“Once a trailblazer for climate protection, where is the UK’s leadership now?” added Anna Krajinska. “The EU is clamping down on airport expansion and integrating non-CO₂ effects into its legislation, whereas the UK government is actively pushing forward with airport expansion, a misguided attempt to generate growth. If the government wants to prosper from aviation, scaling up green fuel production and helping airports to become hubs for these will deliver growth without compromising on UK climate leadership.”