London, 21 March 2025 — In a major disruption to UK air travel, Heathrow Airport has announced a full closure for the entirety of Friday, 21 March, following a fire at an electrical substation that triggered a significant power outage across the airport.
The fire, which occurred in the early hours of the morning, has affected critical systems, forcing the suspension of all inbound and outbound flights until the end of the day.
In an official statement, Heathrow said:
“Heathrow closure – Friday 21 Mar 2025
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 23:59 on 21 March.
Passengers are advised not to travel to the airport and should contact their airline for further information. We apologise for the inconvenience.”
Travel Disruption Across the Board
The full-day closure is impacting all terminals, with thousands of passengers facing cancellations or delays. Travellers are being urged to stay away from the airport and check directly with their airlines for rebooking or alternative arrangements.
With Heathrow being the UK’s busiest airport and a major global travel hub, the impact of this shutdown is expected to ripple across domestic and international travel networks.
Next Steps
Airport officials are continuing to assess the damage and have not yet indicated whether operations will resume as normal tomorrow. Safety remains the airport’s top priority as technical teams work to restore full functionality.
