£284 Cheap United flights from Washington to London (IAD→LHR)

View £284 flight on Wed, 31 Dec 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 £284 for one-way flights and £458 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Sun, 7 Dec - Fri, 26 Dec
IAD
Washington
LHR
London
£458 Return, found 6 days ago
£458
Return
found 6 days ago
Select United flight, departing Sun, 7 Dec from Washington to London, returning Fri, 26 Dec, priced at £458 found 6 days 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 21 mins

Frequently asked questions

How much is a United Airlines flight from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR)?
Grab cheap return United Airlines flights from £458 from IAD to LHR by sorting your results from "Price (lowest to highest)" on Expedia. Or search for bargains from £284 for a one-way trip.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from IAD to LHR with United Airlines?
Browse for one-way or round-trip flights to London in January or February. You could find lower fares with United Airlines during these off-season months.
Does United Airlines fly nonstop from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR)?
Skip the layovers and fly from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR) on any of United Airlines's 14 direct weekly flights. Apply our "Nonstop" and "Airline" filters to find the United Airlines flight that'll get you to LHR at your preferred time.
How long does it take to fly from IAD to LHR with United Airlines?
It takes approximately 7h 21m to fly nonstop from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR) with United Airlines.
Which day of the week has the most United Airlines flights from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR)?
Thursday has the most United Airlines flights from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR). With 2 daily departures, this is the best day to find something that will work for your schedule.
What airports does United Airlines fly into in London?
Catch a United Airlines flight from Washington Dulles Intl. Airport (IAD) to London, and you'll most likely touch down at Heathrow Airport (LHR). This is the airline's primary hub here.
What type of plane does United Airlines fly from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR)?
United Airlines generally flies Boeing 777 planes for flights from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR). This airline also operates the Boeing 767-300 on this route. Remember that aircraft type can change depending on operational demands, so the plane you catch might be different when you travel.
Can I change or cancel my United Airlines flight from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR)?
Depending on the type of fare you purchased, a fee is typically charged if you modify or cancel your booking more than 24 hours after it has been confirmed. To find tickets with more flexibility, select our "No cancel fee" or "Changes included" filter while looking for flights. For more details on cancelling or changing your reservation, head to "Trips," select your flight and click on "Manage Booking."
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