£172 Cheap Flights from Washington (IAD) to London (LHR)

View £172 flight on Thu, 14 Aug 2025Opens in a new window

Popular airlines from Washington Dulles International Airport (IAD) to Heathrow Airport (LHR)

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Cheap Flights from Washington (IAD) to London (LHR)

Prices were available within the past 7 days and start at £172 for one-way flights and £352 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Aer Lingus
Wed, 29 Oct - Fri, 7 Nov
IAD
Washington
LHR
London
£352 Return, found 6 days ago
£352
Return
found 6 days ago
Select Aer Lingus flight, departing Wed, 29 Oct from Washington to London, returning Fri, 7 Nov, priced at £352 found 6 days ago
Iberia
Sun, 16 Nov - Tue, 25 Nov
IAD
Washington
LHR
London
£366 Return, found 1 day ago
£366
Return
found 1 day ago
Select Iberia flight, departing Sun, 16 Nov from Washington to London, returning Tue, 25 Nov, priced at £366 found 1 day ago
British Airways
Mon, 17 Nov - Mon, 24 Nov
IAD
Washington
LHR
London
£374 Return, found 3 days ago
£374
Return
found 3 days ago
Select British Airways flight, departing Mon, 17 Nov from Washington to London, returning Mon, 24 Nov, priced at £374 found 3 days ago
Air France
Mon, 8 Sep - Fri, 19 Sep
IAD
Washington
LHR
London
£376 Return, found 2 days ago
£376
Return
found 2 days ago
Select Air France flight, departing Mon, 8 Sep from Washington to London, returning Fri, 19 Sep, priced at £376 found 2 days ago
Virgin Atlantic
Tue, 9 Sep - Wed, 29 Oct
IAD
Washington
LHR
London
£376 Return, found 4 days ago
£376
Return
found 4 days ago
Select Virgin Atlantic flight, departing Tue, 9 Sep from Washington to London, returning Wed, 29 Oct, priced at £376 found 4 days ago
British Airways
Wed, 30 Jul - Wed, 27 Aug
IAD
Washington
LHR
London
£382 Return, found 3 days ago
£382
Return
found 3 days ago
Select British Airways flight, departing Wed, 30 Jul from Washington to London, returning Wed, 27 Aug, priced at £382 found 3 days ago
Scandinavian Airlines
Wed, 22 Oct - Wed, 5 Nov
IAD
Washington
LHR
London
£392 Return, found 4 days ago
£392
Return
found 4 days ago
Select Scandinavian Airlines flight, departing Wed, 22 Oct from Washington to London, returning Wed, 5 Nov, priced at £392 found 4 days ago
Swiss International Air Lines
Fri, 31 Oct - Sun, 2 Nov
IAD
Washington
LHR
London
£398 Return, found 5 days ago
£398
Return
found 5 days ago
Select Swiss International Air Lines flight, departing Fri, 31 Oct from Washington to London, returning Sun, 2 Nov, priced at £398 found 5 days ago
KLM
Wed, 30 Jul - Wed, 13 Aug
IAD
Washington
LHR
London
£406 Return, found 5 days ago
£406
Return
found 5 days ago
Select KLM flight, departing Wed, 30 Jul from Washington to London, returning Wed, 13 Aug, priced at £406 found 5 days ago
Delta
Wed, 30 Jul - Wed, 13 Aug
IAD
Washington
LHR
London
£406 Return, found 5 days ago
£406
Return
found 5 days ago
Select Delta flight, departing Wed, 30 Jul from Washington to London, returning Wed, 13 Aug, priced at £406 found 5 days ago

Find the cheapest month to fly from Washington (IAD) to London (LHR)

November is typically the cheapest month to fly

From £372 - £554 per traveller.

Graph displaying average flight prices per month

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
Return price
£351
Distance
5866 km
Average flight time
12 hours 25 mins

Compare flights from Washington to London easily and book with confidence

For travelling on business or for pleasure, Expedia makes it easy to book your flights from Washington to London. Operating between them flights per day, 20 airlines cover the route. And fly direct, getting you to Heathrow in just hours. If you have a preferred carrier, use our advanced search tool to find the right flight from Washington Dulles Intl. to Heathrow.  

To make things even better, in the advanced search, you can also choose to fly economy, premium economy, business or first class, select your maximum number of stops, and pick your preferred departure and arrival time. You can also opt for refundable and direct flights. 

Grab a great deal on your flight from Washington Dulles Intl. (IAD) to Heathrow (LHR)

The easiest way to view the best deals on flights from Washington to London today is to enter your travel dates and hit search. From here, you can sort your results by price to see the cheapest flights first. Right now, return flights from Washington Dulles Intl. to Heathrow start at just £352 and range up to £406.  

To find an even better deal, try  

  • being flexible on your dates – midweek flights can be cheaper
  • looking for other airports near Washington and London
  • booking your flight during October, the cheapest month on this route
  • varying your flight times – early morning and late at night are sometimes cheaper 

Why you should book your Washington to London flight with Expedia!

We cater for all flight types, cabin classes and airlines. So whether you’re booking flights from Washington Dulles Intl. to Heathrow for a budget break or a business trip with a bit of pleasure thrown in, we make it easy to secure the seat that’s right for you.  

Thanks to our supersized inventory that offers great choice all in one place, you know you’ll get a great deal with Expedia. Especially if you bundle your flight together with your hotel, you will unlock amazing savings. For added peace of mind, you can choose flexible bookings or filter to find refundable options, so you won’t pay a fee to change your flight.  

Frequently asked questions

How much is a flight from Washington Dulles Intl. Airport (IAD) to Heathrow Airport (LHR)?
Start packing your suitcase, because round-trip journeys from IAD to London Heathrow start from £352. That's based on airfares listed within the last 7 days on Expedia for flights departing within the next year. Prices can change quickly, so book today to nab the best deal. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from Dulles Intl. Airport to Heathrow Airport?
We understand that things come up unexpectedly, so we've made it as easy as possible for you to cancel your trip online. Just head to the Customer Service Portal and follow the instructions.
How do I find cheap flights from Dulles Intl. Airport to Heathrow Airport (LHR) that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you're searching for IAD to Heathrow Airport flights, you'll see a "no change fees" filter for you to select.
How far is the flight from Dulles Intl. Airport to LHR?
You'll have 5,900 kilometres to cover on the long-haul Chantilly to Hounslow route. Dress in layers of comfortable clothes and consider taking a sleep mask and earplugs.
Which airlines fly direct from Washington Dulles Intl. Airport (IAD) to Heathrow Airport?
With 60 flights a month from Dulles Intl. Airport to LHR, United Airlines (UA) is an excellent choice. Another carrier operating on this route is British Airways (BA). You'll have 60 flights every month to choose from.
Are IAD to LHR flight tickets cheaper when they're purchased at the last minute?
Booking your trip from IAD to London Heathrow at the last minute could be your ticket to a great deal. However, it could end up costing a great deal more! If you'd prefer to err on the side of caution, book well ahead of your departure date. In fact, Expedia has some of the biggest bargains up to a year in advance. If your preferred carrier hasn't released tickets yet, check back regularly as deals are updated on Expedia all the time.

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