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Cheap flights from Washington, D.C. Dulles Intl Airport to London Heathrow Airport from C$ 370

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/11. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — LHR
11 Oct — 18 Oct1
1 adult
1 adult, Economy

Cheapflights Tip: The best prices from Washington, D.C. Dulles Intl to London Heathrow are usually found in September or October, booked 63 days in advance, depart on a Thursday or Tuesday and return on a Tuesday

Cheap flight deals from Dulles Intl to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from Dulles Intl (IAD) to Heathrow (LHR). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated 11 September 2025.

Round-trip from

C$ 704

One-way from

C$ 370

Popular in

June

Cheapest in

September

Average price

C$ 933
Scandinavian Airlines
  • Scandinavian Airlines
  • 14/10-17/10
  • 3 total stops
  • 48h 09m total
  • Washington, D.C. to London
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TAP AIR PORTUGAL
  • TAP AIR PORTUGAL
  • 9/11
  • 1 total stop
  • 14h 00m total
  • Washington, D.C. to London
Search Deals
Highest demand for flights based on searches. 14% potential increase in price (C$ 245 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (C$ 46 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in September 2025
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Find flight deals from Dulles Intl to Heathrow

Cheapest flights from Dulles Intl to Heathrow
Explore the most affordable flight options available from Dulles Intl to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 11 September 2025.

Tue 14/1010:05 p.m.IAD - LHR
2 stops29h 50mScandinavian Airlines
Fri 17/106:40 a.m.LHR - IAD
1 stop18h 19mScandinavian Airlines
Deal found 10/9C$ 704
Sun 30/117:40 p.m.IAD - LHR
1 stop10h 10mIcelandair
Fri 12/1212:15 p.m.LHR - IAD
1 stop11h 15mIcelandair
Deal found 11/9C$ 722
Thu 4/127:40 p.m.IAD - LHR
1 stop18h 50mIcelandair
Wed 21/112:15 p.m.LHR - IAD
1 stop11h 15mIcelandair
Deal found 9/9C$ 723
Tue 30/98:30 p.m.IAD - LHR
1 stop18h 50mIcelandair
Thu 9/101:05 p.m.LHR - IAD
1 stop11h 15mIcelandair
Deal found 11/9C$ 725
Sun 12/108:30 p.m.IAD - LHR
1 stop18h 50mIcelandair
Sat 28/38:35 p.m.LHR - IAD
1 stop26h 45mIcelandair
Deal found 11/9C$ 726
Sat 11/1011:15 p.m.IAD - LHR
1 stop31h 40mIcelandair
Tue 21/109:25 p.m.LHR - IAD
1 stop26h 55mIcelandair
Deal found 9/9C$ 728
Fri 10/1011:15 p.m.IAD - LHR
1 stop31h 40mIcelandair
Mon 30/39:25 p.m.LHR - IAD
1 stop26h 55mIcelandair
Deal found 11/9C$ 729
Tue 7/1012:09 p.m.IAD - LHR
2 stops16h 26mScandinavian Airlines
Thu 16/107:05 a.m.LHR - IAD
2 stops17h 54mScandinavian Airlines
Deal found 11/9C$ 730
Mon 29/98:30 p.m.IAD - LHR
1 stop18h 50mIcelandair
Tue 7/101:05 p.m.LHR - IAD
1 stop11h 15mIcelandair
Deal found 11/9C$ 733
Sat 27/911:15 p.m.IAD - LHR
1 stop31h 40mIcelandair
Thu 9/101:05 p.m.LHR - IAD
1 stop11h 15mIcelandair
Deal found 11/9C$ 736
Sat 27/911:15 p.m.IAD - LHR
1 stop31h 40mIcelandair
Sun 5/109:25 p.m.LHR - IAD
1 stop26h 55mIcelandair
Deal found 11/9C$ 739

Cheapflights Fare Finder

 
Customize your flight search to find flights from Dulles Intl to Heathrow that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 629,999 searches. Data last updated 11 September 2025.
Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to London Heathrow Airport that are best for you.

Fly from

Dulles Intl

Fly to

Heathrow

Route

Depart

Return

Price

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Mon 1/12

7:40 p.m.-10:50 a.m.

1 stop10h 10m

London Heathrow

Fri 12/12

12:15 p.m.-6:30 p.m.

1 stop11h 15m

C$ 722

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Tue 2/12

7:40 p.m.-10:50 a.m.

1 stop10h 10m

London Heathrow

Fri 12/12

12:15 p.m.-6:30 p.m.

1 stop11h 15m

C$ 722

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Sun 30/11

7:40 p.m.-10:50 a.m.

1 stop10h 10m

London Heathrow

Fri 12/12

12:15 p.m.-6:30 p.m.

1 stop11h 15m

C$ 722

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Tue 2/12

7:40 p.m.-10:50 a.m.

1 stop10h 10m

London Heathrow

Sat 13/12

12:15 p.m.-6:30 p.m.

1 stop11h 15m

C$ 722

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Mon 1/12

7:40 p.m.-10:50 a.m.

1 stop10h 10m

London Heathrow

Sat 13/12

12:15 p.m.-6:30 p.m.

1 stop11h 15m

C$ 722

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Tue 18/11

7:40 p.m.-10:50 a.m.

1 stop10h 10m

London Heathrow

Sat 22/11

12:15 p.m.-6:30 p.m.

1 stop11h 15m

C$ 723

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Mon 17/11

7:40 p.m.-10:50 a.m.

1 stop10h 10m

London Heathrow

Fri 21/11

12:15 p.m.-6:30 p.m.

1 stop11h 15m

C$ 723

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Wed 3/12

7:40 p.m.-7:30 p.m.

1 stop18h 50m

London Heathrow

Sat 13/12

12:15 p.m.-6:30 p.m.

1 stop11h 15m

C$ 725

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Wed 19/11

7:40 p.m.-7:30 p.m.

1 stop18h 50m

London Heathrow

Tue 25/11

8:35 p.m.-6:30 p.m.

1 stop26h 55m

C$ 726

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Tue 17/2

7:40 p.m.-10:50 a.m.

1 stop10h 10m

London Heathrow

Sun 1/3

8:35 p.m.-6:30 p.m.

1 stop26h 55m

C$ 770

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/9

Showing 1-10 of 23 results
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Best time to book a flight from Dulles Intl to Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow from Dulles Intl with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Washington, D.C. Dulles Intl Airport to London Heathrow Airport

How far ahead should I book a flight from Washington, D.C. Dulles Intl Airport to London Heathrow Airport?

Use this chart to determine the optimal time to book a round-trip flight from Dulles Intl to Heathrow. Price data was last updated on 29 August 2025.

The price you pay for your flight from Washington, D.C. Dulles Intl Airport to London Heathrow Airport may vary depending on when you book. For the best chance of a lower fare, look to book 63 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to London Heathrow Airport?

Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to London Heathrow Airport (average of C$ 560). Flying from Washington, D.C. Dulles Intl Airport to London Heathrow Airport in July is currently the most expensive (average of C$ 856). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from IAD to LHR?

Find hourly flight availability from Dulles Intl to Heathrow. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 11 September 2025.

It’s optimal to fly from Washington, D.C. Dulles Intl Airport to London Heathrow Airport at noon. By choosing this option you can save up to 4% on the cost of your flight, compared to a flight in the morning.

Related info for your journey

Find useful and relevant information for your journey from Dulles Intl to Heathrow. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Washington, D.C. Dulles Intl Airport to London Heathrow Airport?

    There are many flights that can get you from Washington, D.C. Dulles Intl Airport to London Heathrow Airport in 10h 10m. Fly via Icelandair to get the fastest option. There are 5897 km between Washington, D.C. Dulles Intl Airport and London Heathrow Airport.

  • What are the cheapest airlines to fly from Washington, D.C. Dulles Intl Airport to London Heathrow Airport one-way?

    C$ 431 is the cheapest one-way deal found within the past few days, from TAP AIR PORTUGAL. You may also be able to find cheap deals on British Airways and Finnair, with prices starting from C$ 518 and C$ 525, respectively.

  • What are the most reliable airlines from Washington, D.C. Dulles Intl Airport to London Heathrow Airport?

    No one likes to see their flight delayed. When booking a flight from Washington, D.C. Dulles Intl Airport to London Heathrow Airport consider choosing Aeromexico (100%), KLM (70%) or Air France (70%) as they are the most reliable in getting you off to your destination on time.

  • Can I find deals for flights from Dulles Intl to Heathrow that include hotel bookings?

    Yes. In addition to deals on Dulles Intl to Heathrow flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Dulles Intl to Heathrow?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Dulles Intl to Heathrow.

  • Can I find deals for business class flights from Dulles Intl to Heathrow?

    Yes. Cheapflights offers flight deals from Dulles Intl to Heathrow by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to London Heathrow Airport?

    Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to London Heathrow Airport (average of C$ 560). Flying from Washington, D.C. Dulles Intl Airport to London Heathrow Airport in July is currently the most expensive (average of C$ 856). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Travelling to a place near London Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Brentford
Sutton
Hounslow
Slough
Marlow
Leamington Spa
Milton Keynes
Romford
Watford
Bedford
Luton
Southall

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