Gatwick expansion cleared its main legal hurdle on June 23 after the High Court dismissed two judicial review challenges brought by local campaigners, upholding the UK government’s approval of London Gatwick’s £2.2 billion Northern Runway Project and clearing the way for the airport to bring its standby runway into routine use, a move that could add around 100,000 aircraft movements a year at one of Europe’s largest low-cost carrier bases.

High Court judge Mr Justice Mould rejected claims brought by Peter Barclay, chairman of the Gatwick Area Conservation Campaign, and the group Communities Against Gatwick Noise Emissions, confirming that transport secretary Heidi Alexander acted lawfully in granting the project’s development consent order in September 2025.

The privately financed scheme will move Gatwick’s existing northern standby runway 12 metres north so that departing aircraft can use it alongside the main runway, while arriving flights continue to use the main strip. Gatwick expects the work to lift annual passenger capacity by around 13 million and carry the airport towards 80 million passengers a year by 2047.

The airport, 30 miles (48 km) south of London, is the UK’s second-busiest and the world’s busiest single-runway hub, currently handling around 280,000 flights a year. The Department for Transport treated Gatwick as primarily a leisure airport served largely by low-cost carrier flights, a profile central to the case for additional capacity.

Gatwick is slot-constrained, and the extra movements are material to the carriers that base aircraft there, led by easyJet, which operates its largest base at the airport. The Gatwick expansion gives low-cost and leisure operators room to add routes, frequencies and based aircraft at a congested airport where slot scarcity has capped growth.

Alexander approved the scheme in September 2025 and has said the work could be completed by 2029. Gatwick estimates the project will create 14,000 jobs and add £1 billion a year to the economy, figures the airport acknowledges are its own forecasts.

Richard Graybrook, director and head of aviation for UK&I and Europe at consultancy Ramboll, described the ruling as “a significant step forward for the aviation sector.” He said airport expansions “unlock investment, lift critical capacity constraints, strengthen international trade, create much-needed jobs, support local communities and act as a powerful driver of overall economic expansion.”

The Gatwick expansion ruling is not the final word. Under the accelerated timetable for challenges to nationally significant infrastructure projects, any application for permission to appeal must be made within seven days, and both CAGNE and Barclay have said they are considering an appeal. The campaigners had argued the government failed to properly assess the climate impact of the development.

Meanwhile, Gatwick has filed its own legal claim against Alexander over the Airports Slot Allocation (Alleviation of Usage Requirements) Regulations 2026, which cut the proportion of slots airlines must use to retain them from 80% to 70%.

The government introduced the relief citing disruption to shipping through the Strait of Hormuz and the resulting risk to airline schedules; for operators, the lower use-it-or-lose-it threshold changes how easily slots can be held without being flown.