£335 Cheap United flights from Washington to London (IAD→LHR)

View £335 flight on Mon, 4 Aug 2025Opens in a new window

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United flights from Washington to London (IAD→LHR)

Prices were available within the past 7 days and start at £335 for one-way flights and £374 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Sun, 3 Aug - Wed, 20 Aug
IAD
Washington
LHR
London
£374 Return, found 3 days ago
£374
Return
found 3 days ago
Select United flight, departing Sun, 3 Aug from Washington to London, returning Wed, 20 Aug, priced at £374 found 3 days ago
United
Wed, 20 Aug - Wed, 27 Aug
IAD
Washington
LHR
London
£377 Return, found 18 hours ago
£377
Return
found 18 hours ago
Select United flight, departing Wed, 20 Aug from Washington to London, returning Wed, 27 Aug, priced at £377 found 18 hours ago
Flight from Washington to London route information
Origin airport
Washington Dulles Intl.
Destination airport
Heathrow
Airlines serving
Aer Lingus, Air Canada, Air France, American Airlines, Austrian Airlines, British Airways, Brussels Airlines, Delta, Finnair, Iberia, Icelandair, KLM, Lufthansa, Royal Air Maroc, Scandinavian Airlines, Swiss International Air Lines, TAP Portugal, Turkish Airlines, United, Virgin Atlantic
Popular airline
British Airways
Distance
5866 km
Average flight time
12 hours 22 mins
*Available to Expedia members.