Both terminals at Gatwick Airport are suffering a severe water outage, with passengers being given bottled water.
The toilets cannot be flushed and hand-washing facilities are not working at both the North and South terminals.
Passengers posted online saying they were also unable to get coffee or fill up their bottles from water fountains.
Restaurants were also closed.
Bottled water was available for passengers.
Flights are unaffected.
In a statement on social media the airport said: "A local water supply issue is continuing to cause disruption. There is currently no water supply in either terminal.
"Our staff are on hand to support passengers and provide assistance where needed, some restaurant partners have opened to provide additional seating.
"We apologise for the inconvenience caused and are working closely with SES Water to restore the supply as quickly as possible. We will provide further updates as they become available."
SES Water, which serves the airport, said: "We are pleased to provide an update that our Bough Beech water treatment works are back up and running, we now need to treat the water before returning services to normal as quickly as we possibly can.
"We would like to thank customers and our partners at Gatwick Airport for their continued patience, and we are sorry for the inconvenience this is causing."
Residents in Horley and the wider Gatwick area also reported losing their water supply, according to local media.
(c) Sky News 2026: No working toilets or running water at Gatwick as airport suffers major outage
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