Cheap flights from Washington, D.C. Dulles Intl Airport to the United Kingdom from $311

In general, January is the cheapest month to fly from Washington, D.C. Dulles Intl Airport to United Kingdom. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $416. If you aren’t able to travel to United Kingdom during the month of January, then flying in February is also cheap. Prices for this month can be found on momondo for an average of $418.

The cheapest day to depart from Washington, D.C. Dulles Intl Airport to United Kingdom is on a Wednesday when prices can be found for as low as $773. The most expensive day to fly to United Kingdom is Saturday, with ticket prices averaging around $900.

According to our data, the cheapest time of day to fly to United Kingdom is in the afternoon. momondo users have found flights departing from Washington, D.C. Dulles Intl Airport to United Kingdom in the afternoon for as low as $820. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights to United Kingdom are more costly in the evening, with an average ticket price of $856. Departure times in the evening fall within the peak daily travel times, which is why tickets can be more expensive.

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

You are more likely to see cheaper flights to United Kingdom from Washington, D.C. Dulles Intl Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to United Kingdom for around $786 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to United Kingdom from Washington, D.C. Dulles Intl Airport for as low as $732 on momondo.

Icelandair, British Airways, and Air Canada are the most popular carriers operating from Washington, D.C. Dulles Intl to United Kingdom

British Airways, United Airlines and Aer Lingus are the top three most popular airlines that fly to United Kingdom from Washington, D.C. Dulles Intl Airport according to our data. British Airways is the first choice among our users, with 44% of people opting to fly with this airline when traveling to United Kingdom. Keep in mind that there are 17 different airlines that fly to United Kingdom on a routine basis, so you have a few additional options to choose from.

Historically, on average around 20% of flights between Washington, D.C. and United Kingdom have experienced a delay on any given week. The average delay length over the past 12 months has been 168 minutes.

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

Tuesday is statistically the day of the week which experiences the fewest number of delays on this flight route. Friday has historically seen more delays on average compared to the rest of the week.

According to our data, British Airways have had the least number of delays on this route over the last 12 months; with about 15% of their flights experiencing any sort of delay.

The number of flights available between Washington, D.C. Dulles Intl Airport and United Kingdom is 30 per day as of May 2026. The most frequent departure time is 10:00PM, with 83% of daily flights leaving in the evening.

The number of flights available between Washington, D.C. Dulles Intl Airport and United Kingdom is 211 per week as of May 2026. The most frequent departure day is Mon, with 15% of weekly flights leaving on this day.