Heathrow's £33bn Third Runway Could Push Flights to 720,000

Chancellor John Healey said Friday that a third runway at Heathrow Airport has "always been a case for growth," speaking at International Monetary Fund meetings in Bangkok, according to the BBC. The remark lands days after Prime Minister Andy Burnham declined to say whether he supports the £33bn expansion, telling the BBC last month it was "a matter for London and Londoners."

Why did Healey weigh in now?

Healey told reporters that airport expansion, including at Heathrow, had been "a big part of jobs and growth" in recent decades, the BBC reported. He added that the formal government position is unchanged: the Department for Transport's public consultation on its National Policy Statement has closed, officials are reviewing submissions, and "further decisions and announcements will follow." Healey's comments follow those of his predecessor, Rachel Reeves, who made Heathrow expansion central to an argument last year that "a third runway is badly needed" and that the government could not "duck the decision any longer," per the BBC.

Why is Burnham's position different from the chancellor's?

Asked about the project in September, Burnham suggested the decision belonged to the capital rather than Westminster, saying, "I think we ought to hear the voice of people there first. It's not right for me to just jump straight in on the back of the consultation," according to the BBC. That stance put him at odds with Reeves's earlier framing and now with Healey's. Heathrow's consortium of owners has said it needs explicit backing from Burnham before the end of the year to proceed, the BBC reported, raising the stakes on whether the prime minister clarifies his view before 2026 closes.

What would the third runway actually change at Heathrow?

Heathrow currently serves more than 80 million travelers a year across four passenger terminals and two runways, with flights capped at 480,000 a year, according to the BBC. A third runway would allow that cap to rise to 720,000 flights annually — nearly 2,000 a day on average. The £33bn project, as described by the BBC, would require demolishing hundreds of homes, diverting rivers, and rerouting the M25 motorway through a tunnel between junctions 14 and 15.

Heathrow chief executive Thomas Woldbye told BBC Radio 4's Today programme earlier this week that it would be "good to know" the government's position, adding he hoped Burnham would "come along" with the project. Woldbye argued the runway was "not just for Londoners," saying, "Benefits will be felt all over the country because our supply chain reaches all the way from the north all the way to the south of the UK," per the BBC. Separately, he called forgoing the runway a "huge missed opportunity," the BBC reported.

When would the runway actually open?

The new runway was originally scheduled to open by 2035, subject to plans being submitted and approved, the BBC reported. Heathrow has since said the timeline would likely slip four years to 2039 because of planning and regulatory issues. The project has been debated for decades and continues to face opposition from residents, politicians, and climate campaigners, according to the BBC.

What to watch

• Whether Burnham states a formal position before Heathrow's year-end deadline for ownership backing
• The Department for Transport's response to the closed National Policy Statement consultation
• Any shift in Healey's or the Treasury's public framing as the IMF meetings continue
• Further comment from Woldbye or Heathrow's owner consortium on the 2039 timeline

Glossary

National Policy Statement — a Department for Transport document that sets the legal and planning basis for deciding whether a new runway at Heathrow can be approved.

Flight cap — the maximum number of annual flights permitted at Heathrow, currently 480,000, which a third runway would allow to rise to 720,000, per the BBC.

Consortium of owners — the group of investors that owns Heathrow Airport and has said it needs government backing from Burnham this year to advance the expansion.

For now, the gap between Healey's growth framing and Burnham's deference to "London and Londoners" leaves the project's political backing unresolved even as the formal consultation review proceeds inside the Department for Transport, according to the BBC's reporting.