Cheap flights from London Heathrow Airport to Seattle from C$ 727

If you aren’t able to travel to Seattle 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 C$ 917.

Our data shows that Sunday is the least expensive day to fly to Seattle. Tickets to fly out on this day can be as low as C$ 965. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around C$ 1,369. These prices are subject to change though, so be sure to set up a Price Alert for flights to Seattle.

Our most recent data shows that the best time of day to fly to Seattle is at noon. Flights from London Heathrow Airport to Seattle during this time can be as low as C$ 965. Flights in the afternoon are often more expensive with an average ticket price of C$ 1,332.

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

You are more likely to see cheaper flights to Seattle from London Heathrow Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around C$ 1,098 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from London Heathrow Airport for as low as C$ 1,018 on momondo.

There are 2 cabin classes available to choose from on London Heathrow Airport to Seattle flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

No. A direct flight is the cheapest option for a flight between London Heathrow Airport to Seattle.

As of October 2026, prices for London Heathrow Airport to Seattle flights are approximately 36% cheaper when compared to flights at the same time last year.

Historically, on average around 12% of flights between London and Seattle have experienced a delay on any given week. The average delay length over the past 12 months has been 134 minutes.

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

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

According to our data, Delta has had the least delays on this route over the last 12 months, with about 5% of their flights experiencing any sort of delay.

The number of flights available between London Heathrow Airport and Seattle is 9 per day as of October 2026. The most frequent departure time is 5:00p.m., with 54% of daily flights leaving in the afternoon.

The number of flights available between London Heathrow Airport and Seattle is 63 per week as of October 2026. The most frequent departure day is Thu, with 30% of weekly flights leaving on this day.