Cheap Flights London to Seattle from CAD 658

Flight FAQs

• Which airlines offer the cheapest flights from London (LON) to Seattle (SEA)?

  Based on Trip.com data, American Airlines offers one-way fares as low as CAD 658 on Cheapest nonstop routes (e.g. LHR to SEA on Mon, Aug 31), while Icelandair offers Cheapest nonstop round-trips from CAD 853 departing on Tue, Sep 1 and returning on Mon, Sep 7.

• Which airlines offer direct flights from London to Seattle?

  At the moment, you can catch a direct flight from London to Seattle with the following airlines, including: Alaska Airlines Selected airlines are based on historical data collected from flight bookings users made on Trip.com within the last 90 days.

• How long is the flight from London (LON) to Seattle (SEA)?

  It takes about 10 hours 5 minutes to fly from London (LON) to Seattle (SEA).

• When is the best time to book flights from London to Seattle?

  By analyzing data from all airlines on the Trip.com flight calendar, it looks like the best time to book a flight from London to Seattle is around 40 days (6 weeks) in advance, and the best time to fly is usually on Tuesday, Wednesday, and Saturday. Tuesday typically offers the cheapest flights for departure, while Saturday offers the best return deals.

• How many flights are there per week from London to Seattle?

  Based on Trip.com data in the past 4 weeks, there is 33 flight per week flying from London to Seattle. You can check the weekly schedule for popular airlines on this route below: Alaska Airlines: S/M/T/W/T/F/S -- AS5269 (10:24)

• How can I find the best deals on flights from London to Seattle?

  To find best deals on flights from London to Seattle, you can use various tools on Trip.com:
  · Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on Mon, Aug 31, with one-way flights priced at just CAD 658.
  · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is British Airways.
  · Set up price alerts to easily monitor ticket prices without having to check every day.
  · Check Trip.com flight deals and promo codes frequently.
  · Avoid peak season unless you book very early. It seems the peak season for Seattle travel is around July.
  · Get exclusive promo codes for Trip.com app users.

• When is the best time to book a flight from London to Seattle to get the best price?

  The cheapest months to fly from London to Seattle is September, when demand for travel is lower.

• Which upcoming date is the cheapest for flights from London to Seattle?

  After crunching the numbers on our July flight calendar, it's currently cheapest to fly from London to Seattle on July 22, 2026 with Icelandair, with prices starting at CAD 779.

• Which airports can I fly through when travelling to Seattle from London?

  You can land at any one of the following hubs in Seattle, with Heathrow Airport to Seattle-Tacoma International Airport (LHR-SEA) is by far the most common option on this route: King County (Boeing Field) International Airport (BFI) Kenmore Air Harbor Seaplane Base (LKE) Seattle-Tacoma International Airport (SEA).

• What is the time difference between London and Seattle?

  The time difference between Seattle and London is 8h.

• How can I change or cancel my flight ticket from London to Seattle?

  Tickets can only be changed or cancelled if permitted by airline policy. To submit a change or cancellation request, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and segment, and submit a request. Please note that additional charges may apply according to the airline ticket policy. However, if the flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For more details about change and cancellation policies, please check the customer support pages.