Cheap flights from London to Seattle from $338
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from London to Seattle departing on 5/28. 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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United Airlines flights from London to Seattle
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How to get the cheapest flight ticket from London to Seattle
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 London and Seattle?
What is the cheapest month to fly to Seattle?
In general, January is the cheapest month to fly from London to Seattle. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $633. If you don’t want to visit Seattle in January, then you should wait until March to fly from London, when ticket prices are also cheap, with an average price of $657.
What is the cheapest day to depart on your flight to Seattle?
On average, the least expensive day to fly to Seattle from London is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as $796. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Friday is the most expensive day to depart from London because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $1,189.
What is the cheapest time of day to depart on your flight to Seattle?
Flying to Seattle from London at noon is the least expensive time of day to depart. momondo users have found prices as low as $841 when looking at flights departing at noon. Flights to Seattle are more costly in the morning, with an average ticket price of $952. Departure times in the morning fall within the peak daily travel times, which is why tickets can be more expensive.
What is the cheapest London to Seattle/Tacoma Intl flight route?
Fly from London Heathrow to Seattle/Tacoma Intl for the best London - Seattle/Tacoma Intl flight prices
How far in advance should I book a flight to Seattle?
You are more likely to see cheaper flights to Seattle from London when booking 24 weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around $783 when searching 24 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from London for as low as $695 on momondo.
What cabin class options are available on London to Seattle/Tacoma Intl flights?
There are 4 cabin classes available to choose from on London to Seattle/Tacoma Intl 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 London to Seattle/Tacoma Intl?
Aer Lingus and Lufthansa are the most popular carriers operating from London to Seattle/Tacoma Intl
What airlines fly to Seattle?
Delta, British Airways and Virgin Atlantic are the top three most popular airlines that fly to Seattle from London according to our data. Delta is the first choice among our users, with 37% of people opting to fly with this airline when traveling to Seattle. Keep in mind that there are 7 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.
How many flights depart from London to Seattle on average per day?
The number of flights available between London and Seattle is 19 per day as of May 2025. The most frequent departure time is 4:00PM, with 67% of daily flights leaving in the afternoon.
How many flights depart from London to Seattle on average per week?
As of May 2025, 138 flights take off from London and land in Seattle each week. The most common flight departure day for this route is Sun, with 16% of weekly flights taking off on this day.
When to book flights from London to Seattle
Cheap London to Seattle (LON to SEA) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from London to Seattle
How far is London to Seattle/Tacoma Intl by plane?
The straight-line distance from London to Seattle/Tacoma Intl is 4781.3 mi. Flights usually cover this in 9h 45m, depending on flying conditions and air traffic around both airports.
When did momondo last update prices for flights from London to Seattle/Tacoma Intl Airport?
Prices for flights from London to Seattle/Tacoma Intl Airport are refreshed on a daily basis.
How many operators does momondo search for flights from London to Seattle/Tacoma Intl Airport?
There are 7 operators available for flights from London to Seattle/Tacoma Intl Airport as of May 2025.
How old do you have to be to fly from London to Seattle/Tacoma Intl Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from London to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The travel and health documents you'll need for your trip to Seattle/Tacoma Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from London to Seattle?
momondo data reveals that the most frequently booked plane model on the route from London to Seattle is Boeing 787-10 Dreamliner, representing 28.05% of all bookings. The subsequent popular models are Airbus A330-900neo at 24.83%, Boeing 777-300ER at 15.49%, and Boeing 787-9 Dreamliner at 12.81%.
What is the most popular airline from London to Seattle?
Based on momondo bookings for this flight route, the most popular airline on flight routes from London to Seattle is Delta (25% of total bookings). The next most popular airlines are British Airways (24%), Icelandair (15%), and Virgin Atlantic (12%).
Best airlines flying from London to Seattle
Compare and see reviews for airlines that fly from London to Seattle with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $402 | Free Cancellation | Rating 7.0 489 reviews | |||
| PriceFrom $560 | Free Cancellation | Rating 6.6 6,877 reviews | |||
| PriceFrom $575 | Free Cancellation | Rating 7.0 2,726 reviews | |||
| PriceFrom $620 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $635 | Free Cancellation | Rating 7.4 643 reviews | |||
| PriceFrom $674 | Free Cancellation | Rating 7.8 1,342 reviews | |||
| PriceFrom $675 | Free Cancellation | Rating 8.0 7,950 reviews |
Delta Flights From London to Seattle
Across 14 Delta flights from London to Seattle this week, the average price was $896, with the best Delta deals starting from $675 round-trip. 7,950 users have rated Delta on momondo, with an average score of 8.0/10.
KLM Flights From London to Seattle
KLM is also a popular choice for this route. KLM flight deals for London to Seattle start from as low as $674 round-trip, depending on your selected dates, with average KLM deals seen on momondo around $844. KLM operates 14 flights to Seattle from London in an average week. Users have rated it 7.8/10 across 1,342 reviews.
Traveling to a place near Seattle?
Book flights to Seattle if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from London to Seattle?
momondo collates all your flight options in one place and lets you filter them to find the perfect flight from London to Seattle. momondo saves you time and could save you money on your trip.
Can I find flights from London to Seattle with flexible booking policies on momondo?
Yes. momondo allows you to filter the results for London to Seattle flights to just show those with flexible booking policies.
How can momondo help me find flights from London to Seattle?
momondo provides multiple filters to help you find the best flight to Seattle from London. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.
I’m not ready to book a flight from London to Seattle right now. Can momondo alert me if prices change?
If you are simply researching potential flights to Seattle, momondo offers a useful price alert feature which will track prices for flights to Seattle from London and alert you when they change.