A High Court judge has finished dealing with a legal challenge to Gatwick Airport's plans to build a second runway. The court sealed its final order on 19 June 2026, closing a case that was heard on 20 January. The judge's written decision is published online.

In September 2025, the Transport Secretary agreed to let Gatwick expand. This is called a Development Consent Order — it's the formal permission needed before a major airport project can go ahead. The airport then faced a legal challenge in court.

A long road

To understand why this case took so long, you need to know what happened before. In 2020, a court ruled that the Government's national aviation policy was unfair and stopped it being used. This was a problem for Gatwick, because the airport needs that policy in place before it can apply for permission to expand. The Government then re-confirmed the policy, Parliament agreed with it, and Gatwick's planning examination continued. By September 2025, permission was granted.

When Gatwick went to court in January 2026, it was defending that permission against legal challengers. The court's sealed order in June formally closes the High Court part of the case, though the judgment does not say whether the challengers won or lost, or whether anyone plans to appeal further.

Why the speed matters

There are strict rules for challenging these decisions. Anyone objecting must file their case within six weeks, and courts must work fast. The hearing in January — about four months after the September decision — was done at the right pace according to the law.

Other groups also took legal action. Communities Against Gatwick Noise Emissions (CAGNE) and a person named Peter Barclay brought separate cases about the expansion, according to court records from January 2026. The dispute was not just one lawsuit — many objections were filed. Noise and environmental concerns have been the main complaints throughout the whole Gatwick expansion saga.

Where Gatwick actually is

Airport policy is decided in Westminster. But Gatwick is in Surrey and West Sussex, which are in the south of England. These local communities feel the impact of expansion most — extra noise, extra traffic, extra planes. In Scotland or Wales, communities would have more say through their own parliaments. England has a different planning system, and this has always been one of the tensions in how Gatwick's expansion was handled.

What happens next

The permission Gatwick received in September 2025 is now legal and binding, subject to what the judge has decided. For the airport company, investors, and companies in the supply chain watching deadlines, this court decision removes some of the legal uncertainty. It took more than a decade, multiple court battles, and a complete re-confirmation of Government policy — but Gatwick's expansion project now has its legal permissions in place.