Heathrow’s Third Runway Just Lost Four More Years

Heathrow has informed the UK government that it cannot deliver its third runway by 2035, and now expects the expansion to become operational in 2039. The airport’s revised core scenario assumes planning permission is secured by 2029, with the runway opening within a decade of that consent. The 2035 date was set in January 2025, when then-Chancellor Rachel Reeves announced government backing for the scheme as a growth project. Four years have now been added to a programme whose price tag is put at roughly GBP 49 billion, and critics have seized on the slip as evidence that the original timetable was political rather than engineering-led.

The delay is being attributed to planning and regulatory process rather than construction. A scheme of this size requires a Development Consent Order, an airports national policy statement that survives judicial review, and a funding and charging settlement with the economic regulator that determines how much of the cost lands on airlines and, eventually, on ticket prices. Each of those steps has its own timetable and its own opportunity for challenge, and Heathrow’s revised plan effectively budgets three more years just to get to the point where a spade can enter the ground.

Heathrow continues to argue the case on economic grounds, saying the project would create at least 108,000 jobs and channel billions of pounds through UK supply chains. The airport is already the busiest in the United Kingdom and runs its two existing runways at close to full capacity, which is why a single disruption — weather, a control failure, a closed runway — propagates across its schedule so violently. That capacity squeeze does not ease at any point before 2039 under the new plan.

For travellers, nothing changes this year or next. The practical consequence is that the structural shortage of slots at Heathrow now persists into the late 2030s, which keeps fares on the airport’s most congested long-haul routes elevated and keeps pressure on Gatwick, Stansted and Luton to absorb growth. It also hands a longer runway, so to speak, to competing European hubs — Amsterdam, Paris, Frankfurt, Madrid and Istanbul — that have been adding connecting capacity while London argues about a single strip of concrete.

Sources: ITV News London, Simple Flying