$1,663 Cheap Delta flights London (LHR) to Washington (IAD)

Landing cheap one-way Delta Air Lines flights from LHR to IAD from $1,663 on Expedia is easy --- just filter by "Price (lowest to highest)." Alternatively, check out our affordable return fares from $614 for your next exciting getaway.**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.

Landing the best Delta Air Lines deals from LHR to IAD often comes down to booking at the right moment. You can save 17% on international flights when you book 18 to 29 days before takeoff instead of four to five months ahead. What's more, you can pocket 17% on average by buying your tickets on a Sunday rather than a Friday, which is often the most expensive day to book.* It's a good idea to start checking out flights about one month before you want to travel.*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.

To find the earliest departures from LHR to IAD with Delta Air Lines, sort your results by "Morning" and "Early Morning." Booking an early flight generally means cancellations are less likely.**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.

Delta Air Lines makes traveling from LHR to IAD enjoyable with a rewarding loyalty program and an excellent in-flight experience. You also have the chance to earn points with Delta SkyMiles. Don't forget to join Expedia's free One Key™ rewards program to earn OneKeyCash™*, which can be redeemed on future travel.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.