Heathrow Airport closed: More than 1,000 flights disrupted due to electrical substation fire

Editor’s note: This is a developing story. 

No flights will arrive or depart at London Heathrow Airport (LHR) after the U.K. hub was forced to close following a fire at a nearby electrical substation.

The airport will be closed on Friday until at least midnight while power is restored and contingency plans are implemented.

“Heathrow is experiencing a significant power outage across the airport due to a large fire at a nearby electrical substation,” said a Heathrow spokesperson. “Whilst fire crews are responding to the incident, we do not have clarity on when power may be reliably restored.”

“To maintain the safety of our passengers and colleagues, we have no choice but to close Heathrow until 23h59 on 21 March 2025.” the spokesperson added.

Significant disruption

Heathrow said they expect “significant disruption” over the coming days and that passengers should avoid traveling to the airport “under any circumstances” until the airport officially reopens.

Heathrow was the fifth busiest airport in the world as of March 2025, per OAG, servicing 4,296,701 seats.

The hub was due to see over 1,330 scheduled flights on Friday, according to data from aviation analytics firm Cirium. Up to 291,000 passengers could be affected, and the knock-on scheduling effects over the weekend are likely significant.

It is unclear how many of the scheduled flight operations will be canceled and how many may be diverted to nearby airports. As of 8:10 a.m. (GMT), at least seven flights scheduled to land at LHR had been diverted to London Gatwick Airport (LGW).

“We are aware of the situation at Heathrow Airport today and we are supporting by accepting diverted flights as required,” a London Gatwick spokesperson told TPG. “Flights are operating from London Gatwick as normal today.”

London Stansted told TPG that it had the capacity to receive a small number of diverted flights but had “not received any requests” from LHR. At the time of writing, Luton Airport had also not received any requests for help.

One passenger due to fly from LHR to Hong Kong, Amanda Schuman told TPG: “Thai Airlines just canceled at 4:21 a.m. and didn’t offer anything else. No phone call and no alternative option.”

Schuman had originally been due to fly business class with Thai Airlines from LHR, and has been forced to book a new last-minute ticket flying with Turkish Airlines at an inflated cost in a lower cabin.

“The cost difference is not comparable,” Schuman said, “Only economy was left today and we had booked business class flights. Even a premium economy flight was around $1,500 more today than the business single we had booked.”

What caused the fire?

The London Fire Brigade was alerted at 11:23 p.m. GMT to a fire at an electrical substation operated by the National Grid in Hayes after a transformer was found to be alight. The substation is approx 5 miles and just a 15-minute drive from Heathrow Airport.

Ten fire engines and around 70 firefighters were mobilized to respond to the incident, which was brought under control at around 6:28 a.m. GMT. There were no reports of any injuries.

The cause of the fire is currently undetermined, and the LFB is working closely with the Metropolitan Police Service to investigate.

“This was a very visible and significant incident, and our firefighters worked tirelessly in challenging conditions to bring the fire under control as swiftly as possible,” said Pat Goulbourne, Assistant Commissioner of the London Fire Brigade.

The LFB will remain at the scene throughout Friday to assist National Grid in assessing the site.

“A fire at our North Hyde substation in West London has damaged equipment, leading to a loss of power supply in the area,” said a National Grid spokesperson. “We are working at speed to restore power supplies as quickly as possible.”

As of 6:00 a.m., power had been restored to around 62,000 customers; it is currently unclear whether this includes power restoration at Heathrow Airport.

Which airlines are affected?

British Airways had the largest share of flights (51%) scheduled to take off from LHR today, followed by Virgin Atlantic and Lufthansa, according to Cirium data.

As of 10:15 a.m. GMT, British Airways had canceled 257 of its scheduled flights for the day, which,  as per FlightAware, amounts to around 36% of the airline’s schedule.

Heathrow services flights from four major U.S. carriers: American Airlines, Delta Air Lines, United Airlines and JetBlue.

The fire caused chaos on the busy overnight travel corridor from North America to Heathrow, with some planes already in the air when the fire broke out at approximately 11:23 p.m. GMT.

Some flights chose to divert, like British Airways flight 190 from Austin-Bergstrom International Airport (AUS), which diverted to Dulles International Airport (IAD) after three hours and 36 minutes of flying time.

Japan Airlines flight 41 from Haneda Airport (HND) to Heathrow, having completed a large portion of its long-haul sector when the fire broke out, opted to divert to Helsinki Airport (HEL) in Finland.

While this is more than 1,000 miles from London, Helsinki is home to Japan Airlines Oneworld partner Finnair (as well as being another Japan Airlines destination), which the airline may have considered a better option to help get passengers to their final destination than diverting a U.K. airport it does not regularly fly to.

One of the most unfortunate flights affected by this event was Air Canada’s flight 854, departing from Toronto Pearson Airport (YYZ) to Heathrow. With an average flight time of under seven hours across the Atlantic, this flight got around halfway to its destination before diverting to Canada’s Goose Bay Airport (YYR), landing six hours after departure.

This airport was made famous in the Broadway musical “Come From Away” when 7,000 passengers were diverted to Goose Bay following the September 11 event.

What should I do if I’m flying to or from Heathrow?

Due to fly into Heathrow Airport

If you have a flight to Heathrow Airport, check with your operating airline for updates on cancellations, diversions or rerouting plans.

Call centers will likely be busier than usual with long wait times, so the easiest way to check these details will be to access your booking on the airline’s website or app.

It’s a good idea to ensure your contact details are completed and up to date, that you have downloaded and updated your airline’s app and have enabled notifications so you can be alerted as quickly as possible to any updates to your travel plans.

For added insight, you can also Google your flight number at any time for time updates.

While Heathrow currently aims to reopen on Saturday, March 22, with so many aircraft displaced worldwide, the disruptions will likely continue for several days.

Due to fly from Heathrow Airport

If you have a flight booked to depart from Heathrow, the airport is currently closed, and passengers are instructed not to travel to the airport until further notice.

If your travel is urgent, you may wish to consider alternative options from other London Airports or regional U.K. airports.

Note that thousands of displaced passengers may be in a similar position, and seats may be scarce and expensive across all fare classes.

U.K. Airports outside Heathrow (including all other London airports) are currently operating as usual. However, some may receive diverted aircraft, so take-offs and landings may be delayed as runway movements increase.

Am I entitled to a refund or compensation?

Individual airlines may have differing policies on passengers’ ability to change or cancel their flights to and from Heathrow.

This is an unprecedented and rapidly developing incident, so it may take some time for each airline to determine its policy for disrupted passengers.

If you are stranded overnight, such as on a diverted transatlantic flight; a flight forced to return to its origin or a flight canceled before departure, you may be able to recoup reasonable costs for extra meals, hotel nights and ground transportation if this hasn’t already been provided by your airline.

Related: Flight canceled or delayed? Here’s what to do next

Flights canceled or delayed due to this fire are unlikely to be eligible for EU261 compensation, as this was caused by an event outside the individual airline’s control.

Regardless of individual airline policies, under the Department Of Transport (DOT) flight refund policy, you are entitled to your money back — no questions asked — if your international flight to or from the U.S. is canceled and you choose not to travel.

This policy applies to any unflown portion of your ticket and is not voided by something outside the airline’s control, as EU261 compensation may be.

You’ll find these and other passenger rights guarantees on the DOT dashboard.

Related: Getting a refund for a canceled or delayed flight

Bottom line

Following a fire at a nearby power station, London’s Heathrow Airport — the second busiest airport in the world — was forced to close on Friday. Currently more than 1,000 flights are been affected, with more expected to follow as flight operations are thrown out of sync across the weekend.