• Heathrow Airport has welcomed UK Government support for its third runway proposal but is urging swift regulatory clarity from the Civil Aviation Authority (CAA) by mid-December.
• The £33 billion expansion plan includes a 3,500m runway and major terminal upgrades to boost capacity to 150 million passengers annually.
• While the government has selected Heathrow’s proposal as the preferred scheme for policy review, the airport says shareholder backing depends on assurance that early planning costs will be recoverable. Heathrow stresses that timely decisions from the CAA and government are essential to avoid delays and keep the project on track for delivery by 2035.

Following the UK Government’s selection of Heathrow Airport’s third runway proposal as the preferred scheme for review under the Airports National Policy Statement (ANPS), a Heathrow spokesperson has issued a detailed response welcoming the support but urging swift regulatory clarity to maintain momentum.

“We welcome the Government’s support for our scheme to build a third runway at Heathrow – the UK’s gateway to growth,” the spokesperson said.

“Expanding Heathrow will mean more connectivity, increased trade, improved passenger experience and a huge economic boost for the British businesses that will help design and build it. However, we still need further clarity as to how the crucial next phase of the project will be regulated.

We need definitive decisions from the CAA and Government by mid-December so that delay to the project can be avoided and we can get on with delivering this vital project for our customers and for the UK.”

Key elements of Heathrow’s expansion plan

• Heathrow is already 100% privately financed and expansion will be no different.
• Heathrow’s expansion proposal costs £33bn – this includes £21bn for the runway (inclusive of £1.5bn for M25 works) + £12bn for associated terminal infrastructure.
• Heathrow will also invest £15bn into the existing airport to modernise and upgrade current facilities – these works are independent of a third runway and will go ahead regardless of a planning decision for expansion.
• A north-western runway up to 3,500m. This is the only way to provide full long-haul benefits and deliver reliable noise respite through runway alternation (a shorter runway would not allow noise respite for local communities which is why it was discounted by the Airports Commission).
• Increased capacity to serve up to 756,000 flights and 150m passengers. This can only be achieved with our airfield layout and three full-length runways.
• A brand-new terminal ‘T5X’, expanding Terminal 2 and three new satellite terminals.

M25 vs M4 – Heathrow has a tested plan to create a wider, safer stretch of the M25 while keeping motorists on the move. A new section would be built entirely offline, approximately 100 metres to the west of the existing motorway, with traffic switched over upon completion. This section will be future-proofed with additional space for new lanes to be added under the runway at a future point. A shorter runway to the east that avoided the M25 was assessed and deemed unworkable years ago for creating more harm for less benefit.

Crossing the M4 spur is actually more disruptive to traffic, requires up to 1,500 homes to be demolished (double Heathrow’s proposal) and is more complex and costly to deliver because of the surrounding infrastructure. Despite the Arora Group’s claims that their proposal would not impact the M25, the revised plans submitted to Government this month showed they would remove Terminal 5’s junction 14A and tunnel under and bridge over the M25.

Next Steps

The Government wants Heathrow’s third runway to secure planning permission by 2029 with flights operating by 2035. That timeline means starting work on a planning application before the Airports National Policy Statement is finalised (Ministers are due to finalise it by the end of 2026). Given the scale of investment we’d need to make in the planning process, our shareholders will only proceed if the CAA provides certainty that early costs spent before Ministers have finalised the ANPS policy framework are able to be recovered in full. The CAA is expected to provide a decision on this issue in December.