Cheap flights from Washington to London from $328

The cheapest month to fly to London from State of Washington is in January. Flight prices, which tend to average around $707, are often lower during this time because this is during the off-season. The month of March is another great option to travel to London, with average flight prices from State of Washington averaging around $763.

The cheapest day to depart from State of Washington to London is on a Monday. Travelers who choose to depart for London on a Monday will often find tickets for as low as $919. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around $1,038. These prices are subject to change though, so be sure to set up a Price Alert for flights to London.

Flying to London from State of Washington at noon is the least expensive time of day to depart. momondo users have found prices as low as $961 when looking at flights departing at noon. Flights to London are more costly in the evening, with an average ticket price of $999. Departure times in the evening fall within the peak daily travel times, which is why tickets can be more expensive.

Fly from Seattle/Tacoma Intl to London Heathrow for the best Washington - London flight prices

You are more likely to see cheaper flights to London from State of Washington when booking weeks ahead of your departure date. In general, you can expect to find flights to London for around $915 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from State of Washington for as low as $862 on momondo.

There are 4 cabin classes available to choose from on State of Washington to London flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Iberia, Virgin Atlantic, and United Airlines are the most popular carriers operating from Washington to London

Delta, Virgin Atlantic and British Airways are the top three most popular airlines that fly to London from State of Washington according to our data. Delta is the first choice among our users, with 30% of people opting to fly with this airline when traveling to London. Keep in mind that there are 14 different airlines that fly to London on a routine basis, so you have a few additional options to choose from.

The number of flights available between State of Washington and London is 14 per day as of November 2026. The most frequent departure time is 7:00PM, with 56% of daily flights leaving in the afternoon.

The number of flights available between State of Washington and London is 98 per week as of November 2026. The most frequent departure day is Thu, with 19% of weekly flights leaving on this day.