Overview

• Heathrow has lodged a privately funded proposal for a 3,500-metre runway at an estimated £21 billion, forming part of a wider £50 billion expansion to boost flights from 480,000 to 756,000 annually and serve up to 150 million passengers by the mid-2030s.
• The Arora Group’s competing plan features a shorter 2,800-metre runway costing under £25 billion designed to eliminate the need for an M25 diversion and limit construction risk, with operations targeted by 2035.
• Ministers opened a competitive bidding process in mid-2025 and both submissions have triggered a formal review of the Airports National Policy Statement to guide any Development Consent Order.
• Heidi Alexander will conduct environmental and regulatory assessments of both shovel-ready schemes over the summer, with a final government decision expected after summer 2025.
• The expansion bids continue to draw opposition from Sadiq Khan and environmental campaigners over concerns about noise, air quality and compatibility with the UK’s net-zero commitments.