Heathrow expansion has no credible pathway within the United Kingdom’s climate commitments under current policies, the Climate Change Committee said on 16 September 2026.
The independent watchdog said expansion could fit the UK’s carbon budgets and Net Zero target only if ministers require the aviation industry to reach zero emissions by 2050. That would need direct emissions cuts and engineered removals. The climate test in the draft Heathrow Expansion National Policy Statement should explicitly include the 2050 Net Zero target, it said.
Aviation emissions have more than doubled since 1990, while economy-wide UK emissions have halved. Heathrow is responsible for around half of the aviation industry’s emissions. “Emissions from flying are projected to rise, even without Heathrow expansion, and the UK does not currently have a credible plan to bring them down,” said Nigel Topping, chair of the committee.
“Heathrow expansion is not currently compatible with the UK’s Net Zero target. Government needs to ensure that the aviation industry takes responsibility for the emissions it creates and bears the costs of decarbonisation. Those conditions do not exist today,” Topping said. He added: “Every tonne of greenhouse gas emissions makes those impacts worse.”
The committee’s 2050 pathway shares the emissions reduction burden between engineered removals at 36 per cent, lower demand growth at 24 per cent, efficiency at 20 per cent and sustainable aviation fuel at 20 per cent. The industry would pay for sustainable aviation fuel and removals, with the full costs of decarbonisation phased in soon and met no later than 2050.
The watchdog said sustainable aviation fuel and removals are technically viable but uncertain at scale, making contingency policies necessary. It also noted that half of people in England do not fly abroad in a given year. A citizens’ panel strongly disapproved of taxpayers funding aviation decarbonisation.
The committee’s conclusion puts responsibility on ministers and the aviation industry: a larger Heathrow cannot be treated as compatible with climate goals unless firm conditions make the sector account for, and pay for, the emissions its growth creates.
