Government Publishes Updated Heathrow Expansion Policy as Third Runway Plans Move Forward

The government has released a revised planning framework for Heathrow expansion, giving further backing to proposals for a third runway at the airport.

Transport Secretary Heidi Alexander confirmed to MPs that the review of the Airports National Policy Statement has been completed, with a new draft Heathrow Expansion National Policy Statement published on June 18.

The updated policy supports Heathrow Airport Ltd’s £49bn expansion plan, which was submitted last year. The scheme would increase the airport’s capacity by around 50%, allowing it to handle up to 150 million passengers a year and approximately 756,000 flights.

The proposals include a 3,500m north-west runway, a new terminal known as T5X, three additional satellite terminals and major upgrades to existing airport infrastructure. Heathrow has said £21bn would be spent on the runway and airfield works, with £12bn allocated to terminal expansion and £15bn for improvements to current terminals, including the eventual closure of Terminal 3.

The government said the policy review was needed because environmental, climate and planning obligations have changed since the previous statement was designated in 2018.

The draft statement identifies Heathrow Airport Ltd as the statutory undertaker for the expansion, effectively ruling out rival proposals. It also makes clear that any future application must deliver a complete north-west runway scheme, including runway, terminal and supporting infrastructure, although phased construction is expected due to the scale of the project.

The policy does not grant consent for the expansion. Heathrow will still need to submit a Development Consent Order application, which would be examined by the Planning Inspectorate.

The government said any scheme will be assessed against four key tests covering economic growth, climate change, air quality and noise. Expansion must support UK-wide growth, comply with legally binding climate targets, avoid new breaches of air quality limits and ensure noise impacts are no worse than a 2024 baseline, with reductions where possible.

A public consultation on the draft statement is now open and will run until September 1.

Alongside the policy document, the government has published a surface access vision requiring Heathrow to show how additional passenger demand would be managed across road and rail networks, including any necessary transport upgrades.

The Civil Aviation Authority is also developing the regulatory framework for any future expansion, with a focus on affordability, financeability, cost efficiency and consumer protection.

Further guidance on airspace modernisation is expected to follow as the government continues to advance its support for increased airport capacity in the South East.