The cheapest times to fly from LHR to IAD are

  • January 8th to April 1st
  • April 16th to May 20th
  • October 15th to December 9th

based on data collected exclusively by Champion Traveler across tens of millions of flights. Among all the dates above, the very cheapest time to fly from LHR to IAD is late January and early February. Prices can be as high as $1282 for Saturday flights during early August, or as low as $432 for Wednesday flights around late January and early February.


When to Fly to Washington

Flying from London (LHR) to Washington, DC (IAD) will usually cost between $438 to $993 per person if booking more than four weeks in advance. On average the very cheapest time to fly is late January and early February with an average ticket price of $478. Due to high demand the most expensive time to fly is early August, with an average price of $1088. Planning your trip to low-cost times can easily save you $610 on economy flights and even more on first-class flights. Generally, any price below $600 can be considered a good price for a round-trip LHR to IAD flight.

See below for a graph of average weekly prices for the LHR to IAD route. All prices are for round-trip tickets in USD.

LHR to IAD Flight Prices

Compared to other flights, the LHR to IAD flight is cheaper than the average and costs less than the average flight leaving from London. The average price per mile (for a direct flight) is $0.1, which is far below average.


Flight Prices by Day of the Week

Wednesday is usually the cheapest day to fly to IAD, and Monday the cheapest day to fly back into LHR. Saturdays are the most expensive days to fly out or take a return trip. Selecting flights on the least expensive days could save you up to $121 (17%) on this flight.

Departing prices are for round-trip flights returning on the day of departure. For example, a flight departing on Wednesday and returning a week later will cost an average of $587. Return trip prices are from the IAD to LHR flight, and often highlight the quality of our data in showing the same trend.

Departing Prices by Day

Departure Day Prices

Return Trip Prices by Day

Return Day Prices


Nonstop Flights and Layovers

Travelers looking to fly from LHR to IAD can generally find a 0-layover flight. Because there is a direct flight option the real-world direct flight time of 7 hour 35 minutes may be realistic.


Alternative Nearby Airports

Champion Traveler tells you which airports are nearby and whether tickets might be cheaper alternative airports nearby. Sometimes it’s worth it to fly into a closer airport and then commute to your destination. Remember that there is a nonstop flight from LHR to IAD while comparing.

Destination alternative #1: Philadelphia International Airport (PHL) in Philadelphia, PA

  • 135 miles (217 km) away from IAD
  • Usually 24.08% less expensive than IAD
  • Nonstop flights available

See LHR to PHL flights


Flight Hacking LHR to IAD

Flight hacking is when you book two tickets instead of a layover, sometimes with different airlines. You will need to either bring only a carry-on bag (highly recommended) or leave yourself plenty of time to go through security again. Flight hacking is completely allowed, but airlines don’t always tell you the cheapest way to get from LHR to IAD — but Champion Traveler does!

Hack #1: Oslo (LHR > OSL > IAD)

  • Price for both tickets: $478
  • Average savings: $123 (20.42%)

See LHR to CPH flights

Hack #2: Copenhagen (LHR > CPH > IAD)

  • Price for both tickets: $480
  • Average savings: $120 (20%)

See LHR to OSL flights

Hack #3: Dublin (LHR > DUB > IAD)

  • Price for both tickets: $501
  • Average savings: $99 (16.5%)

See LHR to DUB flights


Flight Questions Answered

Still have questions about flying from LHR to IAD? We’ve got answers.

Which airlines fly this route?

You can find 25 major airlines flying this route most often: Aer Lingus, Aeroflot, Aeromexico, Air Canada, Air France, Alaska, Alitalia, American, Austrian, British Airways, Brussels Airlines, Delta, Finnair, Iberia, Icelandair, KLM, LOT, Lufthansa, Royal Air Maroc, SAS, SWISS, Tap Air Portugal, Turkish Airlines, United, Virgin Atlantic, and potentially more during busy seasons.

How far away is it from Washington Dulles International Airport to London Heathrow Airport?

The distance between the two airports is roughly 3667 miles or 5901 kilometers.

How long does it take to fly from LHR to IAD?

The real-world flight time for a nonstop LHR to IAD flight is about 7 hour 35 minutes.

How many flights go between London and Washington, DC?

It depends on the day of the week and the date, but a typical day might have around 64 available flights from LHR to IAD.


Airport Location Info


Departing Airport

Origination code LHR
Origination airport name London Heathrow Airport
City London
Country the United Kingdom
Latitude 51.5
Longitude -0.5

Return Airport

Destination code IAD
Destination airport name Washington Dulles International Airport
City Washington, DC
Country the United States
Latitude 38.9
Longitude -77.5


Other Resources

Please note that while we’ve worked hard to analyzed tens of millions of flights to get you this data, we do not calculate current live prices or guarantee pricing. Please see our partners using the links above for current offers.