Cheap flights from Seattle to London from £158
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to London departing on 8/10. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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How to get the cheapest flight ticket from Seattle to London
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the typical price of a round-trip flight between Seattle and London?
What is the cheapest month to fly to London?
The cheapest month to fly to London from Seattle is in January. Flight prices, which tend to average around £493, are often lower during this time because this is during the off-season. The month of October is another great option to travel to London, with average flight prices from Seattle averaging around £493.
What is the cheapest day to depart on your flight to London?
Our data shows that Tuesday is the least expensive day to fly to London. Tickets to fly out on this day can be as low as £566. When flying out on a Thursday, the most expensive travel day of the week, you can expect to see flight prices from Seattle to London for around £778.
What is the cheapest time of day to depart on your flight to London?
The cheapest time of day to fly to London is in the afternoon when flights can be purchased for as low as £630. Flights in the morning are often more expensive, with an average ticket price of £1,007.
What is the cheapest Seattle/Tacoma Intl to London flight route?
Fly from Seattle/Tacoma Intl to London Heathrow for the best Seattle/Tacoma Intl - London flight prices
How far in advance should I book a flight to London?
You are more likely to see cheaper flights to London from Seattle when booking 9 weeks ahead of your departure date. In general, you can expect to find flights to London for around £598 when searching 9 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from Seattle for as low as £545 on momondo.
What cabin class options are available on Seattle/Tacoma Intl to London flights?
There are 3 cabin classes available to choose from on Seattle/Tacoma Intl to London flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Seattle/Tacoma Intl to London?
Icelandair and WestJet are the most popular carriers operating from Seattle/Tacoma Intl to London
Which airlines fly to London?
Virgin Atlantic, British Airways and Icelandair are the top three most popular airlines that fly to London from Seattle according to our data. Virgin Atlantic is the first choice among our users, with 53% of people opting to fly with this airline when travelling to London. Keep in mind that there are 3 different airlines that fly to London on a routine basis, so you have a few additional options to choose from.
How many flights depart from Seattle to London on average per day?
As of June 2025, 21 flights take off from Seattle and land in London each day. The most common flight departure time for this route is 20:00, with 50% of daily flights taking off in the afternoon.
How many flights depart from Seattle to London on average per week?
148 flights are operational weekly from Seattle to London as of June 2025. The most popular departure day for this route is Mon, with 15% of flights per week taking off on this day.
When to book flights from Seattle to London
Cheap Seattle to London (SEA to LON) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Seattle to London
How far is Seattle/Tacoma Intl to London by plane?
London is 4781.3 mi away from Seattle/Tacoma Intl. Typically, this will take 9h 20m by plane in normal conditions.
When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to London?
Prices for flights from Seattle/Tacoma Intl Airport to London were last updated today.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to London?
There are 3 operators available for flights from Seattle/Tacoma Intl Airport to London as of June 2025.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to London?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to London.
What documentation or ID do you need to fly to London?
The required travel and health documents for your London trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at London. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular plane model from Seattle to London?
Based on momondo bookings for flights between Seattle and London, the leading plane model is Boeing 787-10 Dreamliner, making up 25.85% of the total bookings. Other popular models include Boeing 777-300ER with 22.26%, Airbus A330-900neo with 22.01%, and Boeing 777 with 9.42%.
What is the most popular airline from Seattle to London?
Based on momondo bookings for flights between Seattle and London, the leading airline is Virgin Atlantic, making up 45% of the total bookings. Other popular airlines include Icelandair with 17%, British Airways with 14%, and KLM with 11%.
Best airlines flying from Seattle to London
Compare and see reviews for airlines that fly from Seattle to London with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom £356 | Free Cancellation | Rating 7.0 499 reviews | |||
| PriceFrom £442 | Free Cancellation | Rating 7.4 652 reviews | |||
| PriceFrom £446 | Free Cancellation | Rating 6.6 7,008 reviews |
Virgin Atlantic Flights From Seattle to London
Virgin Atlantic flies from Seattle to London around 14 times per week, with 652 momondo users rating the airline 7.4/10. The cheapest Virgin Atlantic deal from Seattle to London in the last 72 hours was £601 (round-trip), much lower than the average airfare cost of £863 for Virgin Atlantic flights on this route.
British Airways Flights From Seattle to London
Another popular option for Seattle to London flights is British Airways (6.6/10, 7,011 ratings). British Airways flies from Seattle to London around 13 times per week, with deals starting from £607 round-trip and rising to an average price of around £989.
Travelling to a place near London?
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Why should I use momondo to find a flight deal from Seattle to London?
momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Seattle to London . Millions of users trust and use momondo every year so you are in good hands.
Can I find flights from Seattle to London with flexible booking policies on momondo?
Flights from Seattle to London with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.
How can momondo help me find flights from Seattle to London?
Once all potential Seattle to London flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.
I’m not ready to book a flight from Seattle to London right now. Can momondo alert me if prices change?
Yes. momondo can track prices for Seattle to London flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.