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Cheap flights from Washington, D.C. Dulles Intl Airport to London Heathrow Airport from C$ 490

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 21/4. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — LHR
9 Apr — 16 Apr1
1 adult
1 adult, Economy, 0 bags
Cheapflights Tip: The best prices from Washington, D.C. Dulles Intl to London Heathrow are usually found in August or October, booked 63 days in advance, depart on a Wednesday or Monday and return on a Tuesday

Cheap flight deals from Dulles Intl to Heathrow

Enter your travel dates to find the best prices.

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 10 March 2026.

Mon 20/48:20 p.m.
IAD
-
LHR
2 stops15h 05m
Scandinavian Airlines
Mon 27/46:40 a.m.
LHR
-
IAD
2 stops15h 20m
Scandinavian Airlines
Deal found 6/3C$ 817
Fri 25/98:20 p.m.
IAD
-
LHR
2 stops15h 05m
Scandinavian Airlines
Thu 8/106:40 a.m.
LHR
-
IAD
1 stop15h 20m
Scandinavian Airlines
Deal found 6/3C$ 825
Mon 27/48:20 p.m.
IAD
-
LHR
2 stops15h 05m
Scandinavian Airlines
Wed 6/59:05 p.m.
LHR
-
IAD
2 stops24h 55m
Scandinavian Airlines
Deal found 7/3C$ 830
Mon 20/48:20 p.m.
IAD
-
LHR
1 stop16h 20m
Scandinavian Airlines
Tue 28/45:00 p.m.
LHR
-
IAD
1 stop29h 00m
Scandinavian Airlines
Deal found 9/3C$ 832
Tue 27/108:40 p.m.
IAD
-
LHR
1 stop10h 10m
Icelandair
Fri 6/1112:15 p.m.
LHR
-
IAD
1 stop11h 15m
Icelandair
Deal found 9/3C$ 833
Thu 16/48:20 p.m.
IAD
-
LHR
1 stop17h 10m
Scandinavian Airlines
Tue 21/47:50 p.m.
LHR
-
IAD
2 stops26h 10m
Scandinavian Airlines
Deal found 5/3C$ 835
Sat 25/48:20 p.m.
IAD
-
LHR
2 stops17h 30m
Scandinavian Airlines
Thu 7/57:50 p.m.
LHR
-
IAD
2 stops26h 10m
Scandinavian Airlines
Deal found 8/3C$ 839
Thu 1/108:30 p.m.
IAD
-
LHR
1 stop18h 50m
Icelandair
Sun 11/109:25 p.m.
LHR
-
IAD
1 stop26h 55m
Icelandair
Deal found 8/3C$ 840
Thu 30/48:20 p.m.
IAD
-
LHR
2 stops18h 35m
Scandinavian Airlines
Thu 7/57:50 p.m.
LHR
-
IAD
2 stops26h 10m
Scandinavian Airlines
Deal found 6/3C$ 844

Find 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 10 March 2026.

Round-trip from

C$ 817

One-way from

C$ 490

Popular in

June

Cheapest in

August

Average price

C$ 1,077

Good round-trip deal

C$ 904 or less
Scandinavian Airlines
  • Scandinavian Airlines
  • 20/4-27/4
  • 4 total stops
  • 30h 25m total
  • Washington, D.C. to London
Search Deals
Icelandair
  • Icelandair
  • 21/4
  • 1 total stop
  • 10h 25m total
  • Washington, D.C. to London
Search Deals
Highest demand for flights based on searches. 13% potential increase in price (C$ 213 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (C$ 42 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals
Price to beat on a round-trip flight from Washington, D.C. Dulles Intl to London Heathrow.
Search Deals

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 10 March 2026.
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

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Mon 20/4

8:20 p.m.-5:40 p.m.

1 stop16h 20m

London Heathrow

Tue 28/4

5:00 p.m.-5:00 p.m.

1 stop29h 00m

C$ 832

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Sun 10/5

9:50 p.m.-10:40 a.m.

Nonstop7h 50m

London Heathrow

Mon 18/5

1:35 p.m.-7:25 p.m.

1 stop34h 50m

C$ 965

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Tue 28/4

12:45 p.m.-9:35 a.m.

2 stops15h 50m

London Heathrow

Tue 5/5

9:05 p.m.-5:00 p.m.

2 stops24h 55m

C$ 972

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Mon 20/4

10:55 p.m.-11:20 a.m.

Nonstop7h 25m

London Heathrow

Tue 28/4

9:55 a.m.-3:35 p.m.

1 stop10h 40m

C$ 1,018

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Thu 26/3

8:32 a.m.-7:10 a.m.

2 stops18h 38m

London Heathrow

Tue 31/3

5:50 p.m.-2:20 p.m.

1 stop25h 30m

C$ 1,024

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Wed 8/4

10:55 p.m.-11:20 a.m.

Nonstop7h 25m

London Heathrow

Sun 19/4

6:15 a.m.-4:05 p.m.

1 stop14h 50m

C$ 1,027
Quickest round-trip

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Mon 20/4

10:55 p.m.-11:20 a.m.

Nonstop7h 25m

London Heathrow

Mon 27/4

5:55 p.m.-8:55 p.m.

Nonstop8h 00m

C$ 1,057

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Fri 4/9

10:55 p.m.-11:20 a.m.

Nonstop7h 25m

London Heathrow

Fri 11/9

5:55 p.m.-8:55 p.m.

Nonstop8h 00m

C$ 1,057

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Wed 1/4

6:25 p.m.-6:55 a.m.

Nonstop7h 30m

London Heathrow

Sat 11/4

4:40 p.m.-7:55 p.m.

Nonstop8h 15m

C$ 1,057

Washington, D.C.London

IAD - LHR

IADLHR

Washington, D.C. Dulles Intl

Mon 18/5

9:50 p.m.-10:40 a.m.

Nonstop7h 50m

London Heathrow

Mon 25/5

4:25 p.m.-7:25 p.m.

1 stop32h 00m

C$ 1,068

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/3

Showing 1-10 of 22 resultsSorted by cheapest first
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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 6 March 2026.

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, August 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$ 592). Flying from Washington, D.C. Dulles Intl Airport to London Heathrow Airport in June is currently the most expensive (average of C$ 985). 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 10 March 2026.

When flying from Washington, D.C. Dulles Intl Airport to London Heathrow Airport, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

How much does it cost to fly round-trip from Washington, D.C. Dulles Intl Airport to London Heathrow Airport?

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 7h 25m. Fly via Scandinavian Airlines, United Airlines, or Delta to get the fastest option. There are 5897 km between Washington, D.C. Dulles Intl Airport and London Heathrow Airport. This flight may include one or multiple stops.

  • 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 KLM (88%), Air France (88%) or Delta (88%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Washington, D.C. Dulles Intl Airport to London Heathrow Airport?

    While on average a flight from Washington, D.C. Dulles Intl Airport to London Heathrow Airport is generally C$ 906, our data shows the cheapest flight currently is C$ 604. When looking at the most popular route, (Washington, D.C. Dulles Intl - London Heathrow), you can expect to pay C$ 1,312 for that flight.

  • 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, August 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$ 592). Flying from Washington, D.C. Dulles Intl Airport to London Heathrow Airport in June is currently the most expensive (average of C$ 985). 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
Twickenham
Sutton
Gatwick
Slough
Marlow
Cobham
Leamington Spa
Romford
Watford
Bedford
Luton
High Wycombe
Stratford-upon-Avon
Hounslow
Moreton-in-Marsh

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