Massive fire at electrical substation forces unprecedented closure of world’s busiest airport until March 21

LONDON, UK – March 20, 2025 — London’s Heathrow Airport, the world’s busiest by international passenger volume, has been forced to shut down operations entirely today following a massive power outage caused by a fire at a nearby electrical substation.

Officials confirmed that Heathrow will remain closed until 23:59 local time on Thursday, March 21, as crews work to restore power and ensure safety systems are fully operational. Passengers are being advised not to travel to the airport and to contact their airline for further information.

“To maintain the safety of our passengers and colleagues, Heathrow will be closed until 23:59 on 21 March,” said an airport spokesperson. “We sincerely apologise for the inconvenience.”

The sudden outage has triggered global travel chaos, with hundreds of flights cancelled, turned back mid-air, or diverted to other airports across the UK and Europe.

Up to 290,000 Passengers Affected

According to aviation analytics firm Cirium, as many as 290,000 passengers were scheduled to fly to or from Heathrow today — a number large enough to fill Wembley Stadium three times over. Heathrow typically handles over 230,000 passengers daily, and just under 84 million travellers annually, making it by far the UK’s busiest airport, nearly doubling the passenger traffic of its next closest rival, Gatwick.

“This is an unprecedented disruption,” Cirium said in a statement. “The ripple effects will be felt across global aviation networks for at least several days.”

Global Disruption and Economic Impacts

The power outage has affected not only passenger terminals but also air traffic control, baggage handling, and customs systems, bringing Heathrow’s operations to a complete standstill.

Several transatlantic and long-haul flights already en route to London have been diverted to alternate airports including Manchester, Paris Charles de Gaulle, Frankfurt, and Amsterdam Schiphol, straining resources at those facilities. Emergency accommodations are being sought for passengers left stranded at diverted destinations.

Business groups and travel associations are warning of significant economic consequences, particularly with Heathrow serving as a key hub for cargo, business travellers, and global connections.

What’s Next?

Investigations are underway into the electrical fire that triggered the substation failure, though no injuries have been reported. Emergency repair crews are working around the clock to restore power, but officials are cautioning that full service may take longer to resume.

The UK’s Department for Transport and Civil Aviation Authority are monitoring the situation, and contingency plans are being implemented to reroute essential services through other British airports.

Airlines including British Airways, Virgin Atlantic, and Lufthansa are advising passengers to rebook or request refunds, with waivers in place for change and cancellation fees.

Passengers Urged to Stay Away

Heathrow authorities reiterated their call for passengers to stay home and avoid travelling to the airport, where terminals are currently without power, lighting, or functioning security systems.

Live updates are being posted via Heathrow’s website and social media channels.