SEA - LON

$280 Find Cheap Flights from Seattle to London - Compare and Save

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Seattle to London departing on 10/10. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

Save 21% or more on flights. Compare deals from all over the web.

Never overpay with our price tracking tools.

Filter searches by price, airline and more to find your best flights.

Everything you should know

Cheapest round-trip
$642
Multiple Airlines
Fri 9/25Fri 10/2
SEA - STN • 1 stop
Cheapest non-stop
$831
Typical prices: $783-$1,293
British Airways
Wed 12/2Mon 12/7
SEA - LHR • Non-stop
Advice from real travelers
AI-powered summary based on content written by travel experts and KAYAK users. AI can make mistakes.
Delta Premium Select adds 38-inch pitch; BA and Virgin Premium Economy add legroom.
American Main Cabin Extra adds early boarding; SEA Spot Saver speeds security.
Expert advice
Expert advice
+1
+1
Expert advice
Expert advice
+1
Nonstop flights
You can fly direct with Alaska Airlines, British Airways and others. Average duration is 9h 25m
Direct flights
Direct flights
+1
+1
Direct flights
Direct flights
+1
Top routes
Insights
Insights
Insights
Insights
Avoid delays
Most punctual • 94% on-time
Best time • Fewest delays
Insights
Insights
Insights
Insights
Top layover airports
Cheapest • Avg $594 (round-trip)
Shortest trip • 11h 20m (one-way)
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travelers who book at least 3 weeks in advance save around 31% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 23% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to London!
Flight Deals
Booking Insights
Expert advice
Flight Deals

Cheap Flights from Seattle to London (SEA-LON)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Seattle to London that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Seattle to London

Fri, Sep 25 - Fri, Oct 2
Multiple Airlines Logo
3:55 pm - 3:25 pmSEA  Seattle/Tacoma Intl-STN London Stansted
15h 30m1 stop Kastrup Copenhagen
Multiple Airlines Logo
6:20 am - 1:45 pmSTN  London Stansted-SEA Seattle/Tacoma Intl
15h 25m1 stop Kastrup Copenhagen
$642Multiple Airlines
Sun, Sep 27 - Sun, Oct 4
Multiple Airlines Logo
3:55 pm - 5:15 pmSEA  Seattle/Tacoma Intl-STN London Stansted
17h 20m1 stop Kastrup Copenhagen
Multiple Airlines Logo
7:05 am - 1:45 pmSTN  London Stansted-SEA Seattle/Tacoma Intl
14h 40m1 stop Kastrup Copenhagen
$642Multiple Airlines
Sat, Oct 3 - Tue, Oct 6
Scandinavian Airlines Logo
11:08 pm - 4:00 pmSEA  Seattle/Tacoma Intl-LHR London Heathrow
32h 52m2 stops Boston Logan Intl Kastrup Copenhagen
Scandinavian Airlines Logo
6:40 am - 1:45 pmLHR  London Heathrow-SEA Seattle/Tacoma Intl
15h 05m2 stops Stockholm Arlanda Kastrup Copenhagen
$644Scandinavian Airlines
Sat, Sep 19 - Mon, Sep 21
Scandinavian Airlines Logo
3:55 pm - 5:00 pmSEA  Seattle/Tacoma Intl-LHR London Heathrow
17h 05m2 stops Kastrup Copenhagen Stockholm Arlanda
Scandinavian Airlines Logo
7:05 am - 11:20 pmLHR  London Heathrow-SEA Seattle/Tacoma Intl
24h 15m2 stops Oslo Gardermoen New York John F Kennedy Intl
$661Scandinavian Airlines
Thu, Oct 15 - Tue, Oct 20
Icelandair Logo
7:00 pm - 8:20 pmSEA  Seattle/Tacoma Intl-LHR London Heathrow
17h 20m1 stop Reykjavik Keflavik Intl
Icelandair Logo
1:05 pm - 5:55 pmLHR  London Heathrow-SEA Seattle/Tacoma Intl
12h 50m1 stop Reykjavik Keflavik Intl
$701Icelandair
Sat, Sep 26 - Sat, Oct 3
Icelandair Logo
7:00 pm - 11:55 amSEA  Seattle/Tacoma Intl-LHR London Heathrow
32h 55m1 stop Reykjavik Keflavik Intl
Icelandair Logo
9:25 pm - 8:40 pmLHR  London Heathrow-SEA Seattle/Tacoma Intl
31h 15m1 stop Reykjavik Keflavik Intl
$703Icelandair
Sat, Nov 7 - Tue, Nov 10
United Airlines Logo
7:05 pm - 11:50 amSEA  Seattle/Tacoma Intl-LHR London Heathrow
32h 45m1 stop Vancouver Intl
United Airlines Logo
6:50 am - 8:56 pmLHR  London Heathrow-SEA Seattle/Tacoma Intl
22h 06m2 stops Brussels Bruxelles-National Washington, D.C. Dulles Intl
$732United Airlines
Sat, Nov 7 - Tue, Nov 10
United Airlines Logo
8:30 am - 7:10 amSEA  Seattle/Tacoma Intl-LHR London Heathrow
38h 40m3 stops Denver Intl Newark Montreal Pierre Elliott Trudeau Intl
United Airlines Logo
6:50 am - 7:03 pmLHR  London Heathrow-SEA Seattle/Tacoma Intl
20h 13m2 stops Brussels Bruxelles-National Chicago O'Hare Intl
$740United Airlines
Wed, Nov 11 - Fri, Nov 13
Lufthansa Logo
2:50 pm - 1:00 pmSEA  Seattle/Tacoma Intl-LHR London Heathrow
14h 10m1 stop Munich Franz Josef Strauss
Lufthansa Logo
7:40 am - 11:17 pmLHR  London Heathrow-SEA Seattle/Tacoma Intl
23h 37m2 stops Munich Franz Josef Strauss Chicago O'Hare Intl
$753Lufthansa
Tue, Nov 10 - Thu, Nov 12
Lufthansa Logo
7:00 am - 4:50 pmSEA  Seattle/Tacoma Intl-LHR London Heathrow
25h 50m2 stops Chicago O'Hare Intl Frankfurt am Main
Lufthansa Logo
2:30 pm - 9:27 amLHR  London Heathrow-SEA Seattle/Tacoma Intl
26h 57m1 stop Vancouver Intl
$768Lufthansa
Booking Insights

KAYAK's insights & trends for Seattle to London flights

Get data-powered insights and trends into flights from Seattle to London to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Seattle to London?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Seattle to London departing in September.

Flight prices are below average for this route right now.

Flights to London from Seattle usually cost between $701 and $984 in September.
The lowest price found in the past 5 days was $642 on Multiple Airlines (Sep 25-Oct 2).

What is the cheapest Seattle to London flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest return flight from Seattle to London costs $740 on the route between Seattle (SEA) and London Heathrow Airport (LHR). It is also the most popular route.

What’s the cheapest day of the week to fly from Seattle to London?

The average price of all round-trip flights from Seattle to London clicked on KAYAK for each day over the last 12 months.

For Seattle to London, Wednesday is the cheapest day to fly on average and Saturday is the most expensive. Flying from London back to Seattle, the best deals are generally found on Monday, with Friday being the most expensive.

What is the cheapest month to fly from Seattle to London?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Seattle to London, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Seattle to London is January, where tickets cost $643 (return) on average. On the other hand, the most expensive months are June and July, where the average cost of round-trip tickets is $1,210 and $1,040 respectively.

Can I save money by flying with a layover from Seattle to London?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 2 stops layover the cheapest option at $792 on average.

How far in advance should I book a flight from Seattle to London?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Seattle to London, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Seattle to London, you should book around 3 weeks before departure, which saves you about 31% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 5 weeks before departure.

Expert advice

Expert advice for your flight from Seattle to London

 
AI-powered summary based on content written by travel experts. AI can make mistakes.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Our travel experts
Stefanie Waldek

Stefanie Waldek

Expert on Delta

Stefanie Waldek is a freelance space, travel, and design writer based in Saratoga Springs, NY. Her words have appeared in Space.com, Travel + Leisure, Condé Nast Traveler, Architectural Digest, and House Beautiful, among other publications. An expert in aviation and expedition cruising, Stefanie is frequently up in the air or on the sea, likely en route to Antarctica or the Arctic.

Duncan Madden

Duncan Madden

Expert on British Airways and LHR

Duncan is a freelance travel writer, copywriter and book author in constant search of travel stories and the perpetual sensation of being on holiday. He’s never happier than when on a dusty trail in search of empty waves or ducking under the piste tape in search of snowbound solitude. British born, living in Germany, but happiest heading for the horizon. His first book, Found in Translation, explores the etymologies and stories of country names around the world and is out now.

Laura Ratliff

Laura Ratliff

Expert on Virgin Atlantic

Laura Ratliff is a New York-based writer and editor. She lives in downtown Brooklyn with her husband and their beloved dogs. Originally from Texas, she now considers New York City her home. She typically spends more than 200,000 miles on a plane each year and stays in plenty of hotels.

Harriet Baskas

Harriet Baskas

Expert on American Airlines and SEA

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Good to know

Low season

January

Cheapest flight

$280
Best time to beat the crowds with an average 22% drop in price.
Most popular time to fly and prices are also 15% lower on average.
Flight from Seattle to London Gatwick Airport

When to book flights from Seattle to London

Are your dates flexible? Find out the best times to travel from Seattle to London based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

Flights from Seattle to London: the best tips from KAYAK users' own experiences

Insights shared by verified travelers who flew the route from Seattle to London 
MichaelFlew with Delta-May 2026
We like Delta, Alaska and American. Be prepared for a bit of a trek from your arrival gate to Customs and outside services. Heathrow doesn't rank high on my list of major airports.
Verified travelerFlew with American Airlines-Apr 2026
Heathrow is too gigantic to have less than 2 hours of layover time.
Verified travelerFlew with British Airways-Apr 2025
Make sure you have plenty of time between flights if you are delayed.
Verified travelerFlew with British Airways-Feb 2025
Don’t take a flight if you sick, or if you have no choice prepare to stay covered with mask throughout the flight
Verified travelerFlew with British Airways-Apr 2024
Bring a sack lunch -- airport food was very expensive.

FAQs for booking flights from Seattle to London

  • Are there onsite hotels at Heathrow Airport or Gatwick Airport?

    Heathrow Airport features a number of hotels connected directly to its terminals, so visitors have a selection of airports to choose from. In Terminal 4 travelers will find the Hilton London Heathrow Airport and the capsule hotel YOTEL, while in Terminal 5 there is the Sofitel London Heathrow. Gatwick airport also has a variety of hotel options available, such as Hampton by Hilton, YOTELAIR, and Bloc Hotel.

  • Can I fly from Seattle to London non-stop?

    British Airways, Iberia, Virgin Atlantic, Finnair, and Delta Air Lines all offer direct nonstop flights from Seattle to London via Heathrow Airport. Many other airlines also offer one-stop flights to London from Seattle with final destinations varying largely between Heathrow Airport, Gatwick Airport, and London City Airport.

  • What is the quickest way from Heathrow Airport to downtown London?

    The Heathrow Express is the fastest way to get to central London from Heathrow Airport and is conveniently connected to Terminals 2, 3, and 5. There is also a direct London Underground connection via the Piccadilly Line, for those who prefer the cheaper (but slower) method of travel.

  • Should I fly to Heathrow Airport or Gatwick Airport?

    Both airports are conveniently connected via public transport to central London with travel times roughly equal. However, if your final destination is on the south or east side of London, then Gatwick is likely the better option due to its close proximity, while Heathrow is more convenient for destinations on the west and north side.

  • Which is the best arrival airport if I want to visit Buckingham Palace?

    Both London Heathrow Airport (LHR) and Gatwick Airport (LGW) provide direct train and subway links to the Buckingham Palace. LHR sits around 1h away on the Piccadilly subway line, while LGW is approximately 45min away on the Southern train line or Gatwick Express.

  • Where can I store my extra luggage at London Heathrow Airport (LHR)?

    Every terminal at the London Heathrow Airport (LHR) features luggage storage lockers. Those using Terminal 1 should locate the lockers on the lower level on the International Arrivals foyer. Storage duration ranges from 3h to a maximum of 90 days.

  • Are there car rentals at Gatwick Airport (LGW)?

    Numerous car rental agencies provide services at the Gatwick Airport (LGW), with most of their pick-up garages situated at the North and South Terminals of LGW. It’s prudent to make early reservations if you want to get affordable rates.

  • Are there any accessibility services available for travelers at LHR upon their arrival?

    London Heathrow Airport (LHR) has essential amenities like flight vending machines, information screens, and seating in every host area. Those arriving via Terminal 3 will find the host areas post-security, near World Duty Free, after the toilets. Still, the arrival terminal has wheelchair-accessible restrooms, located inside the men's and women's toilets. Dedicated agents are there to guide you through the security clearance.

  • What is the cheapest flight from Seattle to London?

    In the last 5 days, the lowest price for a flight from Seattle to London was $280 for a one-way ticket and $642 for a round-trip.

  • Do I need a passport to fly between Seattle and London?

    Yes, you’ll need a passport to travel to London from Seattle.

  • Which airports will I be using when flying from Seattle to London?

    On your way to London, you’ll fly out from Seattle/Tacoma Intl. You’ll be landing in one of London’s 6 airports: London City, London Gatwick, London Heathrow, London Luton, London Southend, or London Stansted.

  • Which airlines offer Wi-Fi service onboard planes from Seattle to London?

    All the following airlines offer inflight Wi-Fi service on the Seattle to London flight route: Delta, Virgin Atlantic, KLM, Air France, American Airlines, and JetBlue.

  • Which aircraft models fly most regularly from Seattle to London?

    The Boeing 787-10 Dreamliner is the aircraft model that flies most regularly on the Seattle to London flight route.

  • Which airline alliances offer flights from Seattle to London?

    Star Alliance, oneworld, and SkyTeam are the airline alliances operating flights between Seattle and London, with Star Alliance being the most commonly used for this route.

  • On which days can I fly direct from Seattle to London?

    There are nonstop flights from Seattle to London on a daily basis.

  • Which is the best airline for flights from Seattle to London, Alaska Airlines or Delta?

    The two airlines most popular with KAYAK users for flights from Seattle to London are Alaska Airlines and Delta. With an average price for the route of $1,057 and an overall rating of 7.9, Alaska Airlines is the most popular choice. Delta is also a great choice for the route, with an average price of $905 and an overall rating of 7.8.

  • How does KAYAK find such low prices on flights from Seattle to London?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Seattle to London.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Seattle to London?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London from Seattle is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Seattle to London?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to London with an airline and back to Seattle with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Seattle to London?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to London from Seattle up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Seattle to London

  • Looking for a cheap flight? 25% of our users found flights on this route for $374 or less one-way and $935 or less round-trip.
  • Link Light Rail and bus services connect Seattle-Tacoma International Airport to downtown Seattle quickly and efficiently. The Link is just outside the airport on the fourth floor of the adjacent parking garage and runs all the way from the airport to the University of Washington.
  • Families flying with children may want to consider visiting Seattle-Tacoma International Airport’s Playroom. It is the perfect spot to help kids burn off excess energy before their flight. The Playroom is located across from the Seattle Tap Room in the Central Terminal near the A gates.
  • There are many airports in London and travelers should keep their locations in mind when choosing which airport to fly into. London City Airport and Heathrow Airport are the most central of the airports and offer quick, easy access to the heart of London, while Gatwick Airport and London Stansted Airport are on the southside and northside of London, respectively.
  • Looking for a family-friendly activity to help pass the time prior to your flight? Why not check out a live music performance? All throughout the week, live music gigs are performed in Sea-Tac Airport’s various terminals to the enjoyment of passengers.
  • Travelers with flights from Seattle to London via Delta Air Lines may want to consider taking the chance to relax in comfort in one of Delta’s premium lounges. Delta operates two Delta Sky Clubs at Seattle-Tacoma International Airport, with one in Concourse A and the other in the airport’s Rooftop Area. There are also showers available at the Rooftop location.
  • Fly aboard British Airways from Seattle to London and experience its hub at the London Heathrow Airport (LHR). After arrival, you can get access to BA Lounge located in The Concorde Room, Terminal 5. Access to this lounge is restricted to members of the airline's Executive Club or the Oneworld Alliance. If you fly this airline, you’ll enjoy priority clearance at the terminal and security checkpoint as part of the fast lane program.
  • There are two lounges at Seattle-Tacoma International Airport (SEA) situated at Concourse A and South Satellite. Typically, the lounges open 3h before the scheduled flight departs. Children can only access the lounges if accompanied by adults, while infants under 2 years are admitted for free. Still, If you’re flying Economy Class, you can access the lounges at a reduced cost.
  • Travelers with kids through Seattle-Tacoma International Airport (SEA) have their needs catered to. The airport features suites where moms can enjoy privacy while pumping or breastfeeding. You can locate these rooms in Concourse N on the Mezzanine level, or Concourse D on the lower level of D Annex. Other amenities include sinks, chairs and power sockets.
  • Those with early morning departures through Seattle-Tacoma International Airport (SEA) should consider booking a room at one of the many hotels adjacent to the airport. Usually, most of these properties provide complimentary shuttles to and from the airport. Holiday Inn Express Hotel & Suites Seatac, An Ihg Hotel is one such hotel.
  • American Airlines allows you to bring pets such as cats and dogs when flying from Seattle to London. Depending on their sizes, they can travel as a carry-on or be transported through American Airlines Cargo. However, they must bear valid health and vaccination certificates, and you must lock them in their kennels.

Prefer to fly direct from Seattle to London?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Seattle/Tacoma Intl to London.
Find which airlines fly direct from Seattle/Tacoma Intl Airport to London, which days they fly and book direct flights.

Direct departures

Seattle/Tacoma Intl to London

Monday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Tuesday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Wednesday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Thursday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Friday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Saturday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Sunday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

See more direct flights

Direct returns

London to Seattle/Tacoma Intl

Monday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Tuesday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Wednesday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Thursday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Friday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Saturday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

Sunday

Alaska Airlines,British Airways,Delta, +1 more

Alaska Airlines,British Airways, +2 more

See more direct flights

Everything you need to know for your flight from Seattle to London

Other airlines flying from Seattle to London

Flights from the other most popular airlines that fly from Seattle to London according to KAYAK users. Prices are the lowest found on KAYAK over the last 7 days. Price and availability are not guaranteed.