$384 Cheap United flights Washington (IAD) to London (LHR)

View $384 flight on Sun, Aug 10, 2025Opens in a new window

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$384 Cheap United flights Washington (IAD) to London (LHR)

Prices were available within the past 7 days and start at $384 for one-way flights and $405 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Tue, Aug 12 - Tue, Aug 19
IAD
Washington
LHR
London
$405 Roundtrip, found 2 hours ago
$405
Roundtrip
found 2 hours ago
Select United flight, departing Tue, Aug 12 from Washington to London, returning Tue, Aug 19, priced at $405 found 2 hours ago
United
Tue, Aug 12 - Tue, Aug 19
IAD
Washington
LHR
London
$412 Roundtrip, found 2 hours ago
$412
Roundtrip
found 2 hours ago
Select United flight, departing Tue, Aug 12 from Washington to London, returning Tue, Aug 19, priced at $412 found 2 hours ago
United
Tue, Aug 12 - Tue, Aug 19
IAD
Washington
LHR
London
$425 Roundtrip, found 2 hours ago
$425
Roundtrip
found 2 hours ago
Select United flight, departing Tue, Aug 12 from Washington to London, returning Tue, Aug 19, priced at $425 found 2 hours ago
United
Tue, Aug 12 - Tue, Aug 19
IAD
Washington
LHR
London
$444 Roundtrip, found 2 hours ago
$444
Roundtrip
found 2 hours ago
Select United flight, departing Tue, Aug 12 from Washington to London, returning Tue, Aug 19, priced at $444 found 2 hours ago
United
Tue, Aug 12 - Tue, Aug 19
IAD
Washington
LHR
London
$447 Roundtrip, found 2 hours ago
$447
Roundtrip
found 2 hours ago
Select United flight, departing Tue, Aug 12 from Washington to London, returning Tue, Aug 19, priced at $447 found 2 hours ago
United
Tue, Aug 12 - Tue, Aug 19
IAD
Washington
LHR
London
$448 Roundtrip, found 2 hours ago
$448
Roundtrip
found 2 hours ago
Select United flight, departing Tue, Aug 12 from Washington to London, returning Tue, Aug 19, priced at $448 found 2 hours ago
United
Tue, Aug 12 - Tue, Aug 19
IAD
Washington
LHR
London
$449 Roundtrip, found 2 hours ago
$449
Roundtrip
found 2 hours ago
Select United flight, departing Tue, Aug 12 from Washington to London, returning Tue, Aug 19, priced at $449 found 2 hours ago
United
Tue, Aug 12 - Tue, Aug 19
IAD
Washington
LHR
London
$450 Roundtrip, found 2 hours ago
$450
Roundtrip
found 2 hours ago
Select United flight, departing Tue, Aug 12 from Washington to London, returning Tue, Aug 19, priced at $450 found 2 hours ago
Flights from Washington (IAD) to London (LHR)
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
Austrian Airlines
Distance
3666 mi
Average flight time
12 hours 25 mins

Frequently asked questions

How much is a United Airlines flight from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR)?
Make use of the "Price (lowest to highest)" filter on Expedia to find cheap United Airlines return flights from $405 from IAD to LHR. Affordable one-way options from $384 are available as well.**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?
January is one of the most affordable months to fly to London with United Airlines. You could also find excellent prices on return and one-way tickets in February.
What is the cheapest time to book flights from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR) with United Airlines?
Search for United Airlines flights from IAD to LHR about one month before you want to leave. The cheapest time to reserve an international flight is usually 18 to 29 days ahead of your travel date when you can save 17% versus booking four to five months in advance. No matter your ticket type or itinerary, the best day to book international airfare is usually Sunday. Friday is often the most expensive. Passengers who book on a Sunday can save 17% on average compared to those who book on a Friday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does United Airlines fly nonstop from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR)?
Depart on one of United Airlines's 14 direct weekly flights from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR). To see what's available, enter your destination, origin and dates and hit search. Next, apply the "Nonstop" and "Airline" filters.
How long does it take to fly from IAD to LHR with United Airlines?
It takes around 7h 21m to travel 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 suit your schedule.
What is the earliest United Airlines flight from IAD to LHR?
Jetting off from IAD at 6:25PM UTC-5, the earliest United Airlines flight to LHR lands at 6:40AM UTC+0. Flying earlier in the day means you're less likely to encounter cancellations or delays.* Not a morning person? The last United Airlines flight from IAD to LHR departs at 10:30PM UTC-5 and touches down at 11:05AM UTC+0.*Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does United Airlines fly into in London?
United Airlines flights from Washington Dulles Intl. Airport (IAD) to London touch down at Heathrow Airport (LHR). This is the main gateway to this city.
Why fly with United Airlines from IAD to LHR?
A rewarding loyalty program and the ability to rack up points through United Mileage Plus are the start of the reasons to depart from IAD to LHR with United Airlines. Plus, when you sign up to Expedia's free One Key™ program, you can receive OneKeyCash™* in addition to United Airlines's loyalty program earnings. It's yours to spend on future travel plans.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
What type of plane does United Airlines fly from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR)?
You'll likely be on a Boeing 777 or a Boeing 767-300 when flying United Airlines from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR). However, keep in mind that a different aircraft could be assigned to your route due to operational reasons.
Can I change or cancel my United Airlines flight from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR)?
Depending on your ticket type, a fee will generally apply if you cancel or reschedule your booking more than 24 hours after it's confirmed. To find tickets with more flexibility, select our "Changes included" and "No cancel fee" boxes while looking for flights. For additional information on changing or canceling your reservation, visit "Trips," select your flight and tick "Manage Booking."

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