London’s Heathrow Airport has been closed until midnight today due to a “significant power outage” caused by a fire at a nearby electrical substation, officials said.
“Due to a fire at an electrical substation supplying the airport, Heathrow is experiencing a significant power outage. To maintain the safety of our passengers and colleagues, Heathrow will be closed until 11.59pm on 21 March,” the airport’s official account on X said, advising passengers to not travel to the airport.
“Significant disruption is expected over the coming days,” a Heathrow spokesperson said.
Follow live updates on the situation here
A statement from the London Fire Brigade stated that 10 fire engines and around 70 firefighters were tackling the fire, which broke out at an electrical substation on Nestles Avenue in Hayes.
“Firefighters have led 29 people to safety from neighbouring properties, and as a precaution, a 200-metre cordon has been established, with around 150 people evacuated. Due to the significant amount of smoke, we strongly advise local residents to keep their windows and doors closed,” said assistant commissioner Pat Goulbourne.
Due to a fire at an electrical substation supplying the airport, Heathrow is experiencing a significant power outage.
— Heathrow Airport (@HeathrowAirport) March 21, 2025
To maintain the safety of our passengers and colleagues, Heathrow will be closed until 23h59 on 21 March.
Passengers are advised not to travel to the airport… pic.twitter.com/7SWNJP8ojd
“This will be a prolonged incident, with crews remaining on scene throughout the night. As we head into the morning, disruption is expected to increase, and we urge people to avoid the area wherever possible.”
The closure has caused major travel disruptions, with at least 120 Heathrow-bound flights forced to divert, according to FlightRadar24. Flights have been rerouted to destinations like Paris, Shannon, and Washington, DC, while some US-bound planes even turned back mid-air.
London-Heathrow will be closed for ALL of Friday due to a “significant power outage” caused by a fire in an electrical substation.
— Flightradar24 (@flightradar24) March 21, 2025
There are currently 120 aircraft in the air that will be diverting to alternate airports or returning to their origins. https://t.co/TEHf2kJO23 pic.twitter.com/Lot0lsJLz8
What are my rights if my flight is cancelled?
Under UK law, a passenger is covered if they are departing from an airport in the UK on any airline, arriving at an airport in the UK on an EU or UK airline, or arriving at an airport in the EU on a UK airline.
If a flight is cancelled, the airline must provide a passenger with care and assistance, meaning they must supply them with food and drink (often provided in the form of vouchers), means to communicate (often by refunding call costs), accommodation if the passenger is given a new flight the following day, and transport to and from the accommodation or their home.
The airline must provide a passenger with these items until it is able to fly them to their destination, no matter how long the delay lasts or what has caused it, the Civil Aviation Authority says.
Sometimes airlines are unable to arrange care and assistance if they are stretched during major disruptions, meaning the passenger can arrange the care themselves and claim the cost back later by keeping receipts.

The Independent’s travel correspondent Simon Calder says: “Whatever the cause of a cancellation, and regardless of the amount of notice that is given, you can insist upon replacement transport: the airline must get you to your destination as soon as possible if that is what you want.
“The UK Civil Aviation Authority says that means if a flight is available on the original day of travel, the passenger must be booked on it – even if it is on a rival carrier.”
Passengers can choose between getting an alternative flight or receiving a refund if their flight is cancelled.
If a passenger received less than 14 days’ notice of a cancellation, they may also be able to claim compensation. However, this is unlikely if the cancellation was not the airline’s fault.
Situations such as extreme weather, strikes, or other “extraordinary circumstances” are not eligible for compensation.
UK attractions still lagging behind pre-Covid visitor numbers as tourists stay away
Passport fees to rise again to record high – up 25 per cent in two years
British couple give up home to tour Canada with cat in ‘Vaniel Craig’
Best museums to visit in the UK 2025
MH370: 10 years on, what we know about the vanishing Malaysia Airlines jet
MH370, 11 years on: What we know – and what we don’t – about the vanished jet