£320 Cheap United flights from Washington to London (IAD→LHR)

View £320 flight on Thu, 26 Mar 2026Opens 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 £320 for one-way flights and £405 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Sun, 20 Jul - Fri, 1 Aug
IAD
Washington
LHR
London
£405 Return, found 1 day ago
£405
Return
found 1 day ago
Select United flight, departing Sun, 20 Jul from Washington to London, returning Fri, 1 Aug, priced at £405 found 1 day 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
Aer Lingus
Distance
5866 km
Average flight time
12 hours 25 mins
*Available to Expedia members.