NZ$742 Cheap Flights London to Washington (LHR-IAD)

Within the past 7 days on Expedia, for flights departing within the next year, the lowest price advertised for a round-trip journey between London Heathrow and Dulles Intl. Airport was NZ$989. Fares this cheap don't wait forever, so make sure you book yours ASAP. Prices and availability are subject to change. Additional terms apply.

This can differ from airline to airline, as each has its own terms and conditions. Visit the Customer Service Portal, where you'll find easy instructions on how to cancel your flight online.

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 Heathrow Airport to Dulles Intl. Airport flights, you'll see a "no change fees" filter for you to select.

With around 5 900 kilometres separating Heathrow Airport and IAD, your flight will be a long one. Pack wisely to make your time on board comfortable. Simple things like warm clothes and some noise-cancelling headphones can make the biggest difference.

United Airlines (UA) is a popular choice. It offers 60 flights between LHR and Washington Dulles Intl. Airport (IAD) each month. You could also have a look at the airfares with British Airways (BA). This airline operates 60 flights every month between Hounslow and Chantilly.

Flight prices fluctuate, so not always. While last-minute deals between LHR and Washington Dulles Intl. Airport (IAD) are of course possible, it's also a good idea to keep a close eye on prices well before you fly. In fact, some air carriers publish their prices up to a year ahead of the departure date. Expedia is constantly updating the best bargains around, so check back often and be ready to grab your seat when fare prices drop.