Cheap flights from London to Washington, D.C. from $521

In general, September is the cheapest month to fly from London to Washington, D.C. Dulles Intl Airport. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $652. If you aren’t able to travel to Washington, D.C. Dulles Intl Airport during the month of September, then flying in January is also cheap. Prices for this month can be found on momondo for an average of $664.

Our data shows that Thursday is the least expensive day to fly to Washington, D.C. Dulles Intl Airport. Tickets to fly out on this day can be as low as $748. When flying out on a Tuesday, the most expensive travel day of the week, you can expect to see flight prices from London to Washington, D.C. Dulles Intl Airport for around $900.

Flying to Washington, D.C. Dulles Intl Airport from London in the afternoon is the least expensive time of day to depart. momondo users have found prices as low as $806 when looking at flights departing in the afternoon. If you have a flexible travel schedule, then try to avoid flying at noon when prices are $841 on average. Flights to Washington, D.C. Dulles Intl Airport from London at noon are generally more expensive because this time of day is more convenient for travelers’ schedules.

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 $740 when searching weeks out. 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 $691 on momondo.

There are 4 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 11% 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 11% more expensive when compared to flights at the same time last year.

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

British Airways, United Airlines and Lufthansa are the top three most popular airlines that fly to Washington, D.C. Dulles Intl Airport from London according to our data. British Airways is the first choice among our users, with 49% of people opting to fly with this airline when traveling to Washington, D.C. Dulles Intl Airport. Keep in mind that there are 12 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 in the morning have, in the past, seen delays more frequently in comparison.

Saturday is statistically the day of the week which experiences the fewest number of 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 least number of delays on this route over the last 12 months; with about 10% of their flights experiencing any sort of delay.

Dublin (DUB) was the most common stop: 50% of momondo users choosing 1-stop flights on this route connected there.

Flights via Copenhagen (CPH) offer the lowest average round-trip price of $575.

Flights connecting via Reykjavik (KEF) have the shortest average one-way travel time: 11h 15m.

Reykjavik (KEF) has the shortest average layover time for this route: 1h 10m.

As of March 2026, there are 23 flights per day flying from London to Washington, D.C. Dulles Intl Airport. The most common time of day flights depart is 4:00PM, with 100% of flights taking off in the afternoon.

165 flights are operational weekly from London to Washington, D.C. Dulles Intl Airport as of March 2026. The most popular departure day for this route is Tue, with 16% of flights per week taking off on this day.