Cheap flights from London to Washington, D.C. from £405

The month of September is, on average, the cheapest month to fly to Washington, D.C. Dulles Intl Airport from London, with most prices found around £487. If you aren’t able to travel during the month of September, then book flights to Washington, D.C. Dulles Intl Airport from London during January instead. Flights to Washington, D.C. Dulles Intl Airport in January, while not as cheap as those in September, still average around £496.

According to our data, Thursday is the cheapest day to fly to Washington, D.C. Dulles Intl Airport from London. The lowest ticket price found for a Thursday departure recently was £578. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. On the other hand, Sunday is the most expensive day to depart from London because it is more convenient for both business and leisure travellers. As a result, prices tend to be around £627.

The cheapest time of day to fly to Washington, D.C. Dulles Intl Airport is at midday when flights can be purchased for as low as £578. In contrast, the most expensive time of day to depart to Washington, D.C. Dulles Intl Airport is in the morning when prices are around £593.

Fly from London Heathrow to Washington, D.C. Dulles Intl for the best London - Washington, D.C. Dulles Intl flight prices

You are more likely to see cheaper flights to Washington, D.C. Dulles Intl Airport from London when booking weeks ahead of your departure date. In general, you can expect to find flights to Washington, D.C. Dulles Intl Airport for around £552 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Washington, D.C. Dulles Intl Airport from London for as low as £516 on momondo.

There are 3 cabin classes available to choose from on London to Washington, D.C. Dulles Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

You could potentially save up to 29% on your flight if you consider stops on a London to Washington, D.C. Dulles Intl Airport flight.

As of March 2026, prices for London to Washington, D.C. Dulles Intl Airport flights are approximately 10% more expensive when compared to flights at the same time last year.

SWISS, Austrian Airlines, and Avianca are the most popular carriers operating from London to Washington, D.C. Dulles Intl

Virgin Atlantic, British Airways and Lufthansa are the top three most popular airlines that fly to Washington, D.C. Dulles Intl Airport from London according to our data. Virgin Atlantic is the first choice among our users, with 46% of people opting to fly with this airline when travelling to Washington, D.C. Dulles Intl Airport. Keep in mind that there are 16 different airlines that fly to Washington, D.C. Dulles Intl Airport on a routine basis, so you have a few additional options to choose from.

Historically, on average around 17% of flights between London and Washington, D.C. have experienced a delay on any given week. The average delay length over the past 12 months has been 129 minutes.

Generally, flights departing in the evening tend to experience fewer delays. Flights departing in the morning have, in the past, seen delays more frequently in comparison.

Saturday is statistically the day of the week that experiences the fewest delays on this flight route. Thursday has historically seen more delays on average compared to the rest of the week.

According to our data, Virgin Atlantic have had the fewest delays on this route over the last 12 months, with about 10% of their flights experiencing any sort of delay.

Reykjavik (KEF) was the most common stop: 41% of momondo users choosing one-stop flights on this route connected there.

Flights via Zurich (ZRH) offer the lowest average return price of £433.

Flights connecting via Reykjavik (KEF) have the shortest average one-way travel time: 11h 21m.

Reykjavik (KEF) has the shortest average stopover time for this route: 1h 26m.

17 flights are operational daily from London to Washington, D.C. Dulles Intl Airport as of March 2026. The most popular departure time for this route is 16:00, with 100% of flights per day taking off in the afternoon.

The number of flights available between London and Washington, D.C. Dulles Intl Airport is 124 per week as of March 2026. The most frequent departure day is Tue, with 21% of weekly flights leaving on this day.