Heathrow Airport has warned that its long-awaited third runway may not become operational until 2039, signalling a possible delay to the timetable for one of Britain's biggest
infrastructure projects.
The airport said its immediate priority was to secure planning approval by 2029. If permission is granted on schedule, Heathrow expects construction and associated works to take up to a decade, putting the potential opening date in 2039.
"Our focus has always been to secure planning permission by 2029. Once achieved, the runway will be open within a decade," a Heathrow spokesperson said in a statement.
The airport had previously described 2035 as an ambitious target for the new runway. It now says meeting that earlier deadline would require substantial changes to existing regulations and government policy.
Heathrow said that opening the runway within 10 years of receiving planning permission remains its core scenario.
The expansion has received backing from the Labour government, which endorsed Heathrow's third-runway plans last year as part of efforts to strengthen Britain's infrastructure and promote long-term economic growth.
The wider expansion programme has been estimated at around £49 billion ($64.92 billion). This includes approximately £15 billion in upgrades that had already been planned, while the construction of the new runway, the diversion of the M25 orbital motorway and development of a new terminal are expected to account for about £33 billion.
The proposed expansion would significantly increase Heathrow's capacity at a time when the airport is already operating close to its limits. Located west of London, Heathrow is currently Europe's busiest airport and has two runways.
The scale of the proposed development would also bring Heathrow closer to the capacity of several major European competitors. Paris Charles de Gaulle and Frankfurt airports each operate four runways, while Amsterdam Schiphol has six.
The third-runway proposal has been debated for decades, with supporters arguing that additional capacity would improve Britain's international connectivity and create opportunities for trade and investment. The project has also faced longstanding concerns over its cost, environmental impact and effects on communities around the airport.
For now, Heathrow's latest timetable places the focus firmly on the planning process. If approval is secured by 2029, the airport says the new runway could be completed within the following decade, making 2039 the latest indication of when the expansion could potentially begin operating. Photo by Warren Rohner, Wikimedia commons.
