Guidance

Letter to potential promoters of Heathrow expansion

Published 30 June 2025

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This publication is available at https://www.gov.uk/government/publications/proposals-for-heathrow-expansion-information-for-potential-promoters/letter-to-potential-promoters-of-heathrow-expansion

From the Secretary of State
Rt Hon Heidi Alexander MP
Great Minster House
33 Horseferry Road
London
SW1P 4DR

Dear promoter,

The government supports expansion at Heathrow Airport and has invited proposals for a third runway to be brought forward by this summer. This invitation for proposals is not part of the development consent order (DCO) process. The government recognises that proposals will not yet be at a level of maturity that is required by the DCO process and that proposals will continue to be developed after submission.

The government’s clear objective is to enable the delivery of an operational third runway by 2035, with applications for planning consent coming forward in time to enable decisions to be made this Parliament. The expansion scheme should seek to maximise cross-economy growth opportunities and value for money. Scheme costs should be minimised for passengers, customers, and government by financing through private funding, including any surface transport costs. All proposals should demonstrate how they are compatible with the UK’s legal, environmental and climate obligations, including in relation to local noise and air pollution.

The government has previously engaged with potential promoters who have indicated that they are bringing forward proposals. To support any potential promoters, we have outlined below the essential information required in initial plans this summer, reflecting discussions on what the government expects at this stage. We will assess all proposals against the criteria set out in this letter and announce next steps in the autumn. As proposals may be used to support the review of the Airports National Policy Statement (ANPS), we ask that proposals set out key areas of divergence from requirements specified in the current ANPS where applicable.

Please see below the essential information required:

Airport scheme design

  • location of proposed development
  • scope of project, including associated enabling elements (for example a terminal, any road changes required to construct the project)
  • land use
  • capacity uplift provided by the proposed expansion, including passenger numbers and air transport movements (ATMs) the infrastructure is capable of supporting by year – along with supporting information on these assumptions if it is material to the numbers of ATMs (e.g. long/short haul assumptions), or any network assumptions

Expected timelines

  • plans for delivering an operational third runway by 2035, including sight of planned timelines for:
    • statutory consultation
    • development consent order (DCO) application, working towards securing development consent this Parliament
    • construction timeline
    • phasing of release of runway and terminal capacity by year, if different phases or staged terminal builds are proposed

Costs and revenues

The following should be considered with the ambition of maximising economic growth opportunities for the UK while minimising costs for consumers, customers, and government:

  • expected incremental impact on overall revenues and airport charges per passenger per year, with details of underlying analysis, modelling and assumptions
  • information on expected costs by year, with details of the underlying analysis and assumptions

Ownership, financing and funding

  • details of the commercial model used, including key assumptions underpinning it
  • demonstration of ability to finance the scheme

Deliverability

  • technical assurance that the plans are feasible and can be reasonably delivered to timetables within the proposal
  • details of any discussions and endorsements from airlines on proposals

Environmental implications and planned mitigations

All proposals should ensure that plans are compatible with the UK’s legal, environmental and climate obligations and consider:

  • direct and indirect impacts, taking both construction and operation of a third runway by 2035 into account
  • air and noise pollution
  • decarbonisation targets, including an assessment of the whole life carbon impacts of the proposal
  • night period operations
  • impacts on the local community regarding health, wellbeing and quality of life
  • surface access mode share targets, including elements of a surface access strategy covering changes to highways, rail, and any assumptions on parking, public transport, and active travel to achieve any targets set

Upon receipt, all proposals for the expansion of Heathrow Airport will be held in the strictest commercial confidence, subject to both the Freedom of Information Act and Environmental Information Regulations. If a request for information is received, it will be considered on a case-by-case basis and the government will consult any third party prior to releasing any information.

As announced by the Chancellor, the government will move at speed to review the Airports National Policy Statement. The government may engage further with promoters who submit proposals.

Submit your proposal

Proposals for a third runway at Heathrow Airport should be sent to heathrowproposals@dft.gov.uk. We look forward to receiving proposals by 31 July 2025.

[SIGNED]

Rt Hon Heidi Alexander MP
Secretary of State for Transport

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