฿8,965 Cheap Flights from Seattle (SEA) to London (LON)

View ฿8,965 flight on Mon, 21 Jul 2025Opens in a new window

Popular airlines from Seattle-Tacoma International Airport (SEA) to London

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Cheap Flights from Seattle (SEA) to London (LON)

Prices were available within the past 7 days and start at ฿8,965 for one-way flights and ฿17,875 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Icelandair
Fri, 1 Aug - Mon, 25 Aug
SEA
Seattle
LGW
London
฿17,875 Return, found 2 days ago
฿17,875
Return
found 2 days ago
Select Icelandair flight, departing Fri, 1 Aug from Seattle to London, returning Mon, 25 Aug, priced at ฿17,875 found 2 days ago
Icelandair
Fri, 1 Aug - Mon, 25 Aug
SEA
Seattle
LGW
London
฿17,930 Return, found 2 days ago
฿17,930
Return
found 2 days ago
Select Icelandair flight, departing Fri, 1 Aug from Seattle to London, returning Mon, 25 Aug, priced at ฿17,930 found 2 days ago
Icelandair
Sat, 2 Aug - Sat, 9 Aug
SEA
Seattle
LHR
London
฿18,605 Return, found 2 days ago
฿18,605
Return
found 2 days ago
Select Icelandair flight, departing Sat, 2 Aug from Seattle to London, returning Sat, 9 Aug, priced at ฿18,605 found 2 days ago
Delta
Wed, 16 Jul - Wed, 30 Jul
SEA
Seattle
LHR
London
฿20,460 Return, found 2 days ago
฿20,460
Return
found 2 days ago
Select Delta flight, departing Wed, 16 Jul from Seattle to London, returning Wed, 30 Jul, priced at ฿20,460 found 2 days ago
Air France
Wed, 16 Jul - Wed, 30 Jul
SEA
Seattle
LHR
London
฿22,180 Return, found 2 days ago
฿22,180
Return
found 2 days ago
Select Air France flight, departing Wed, 16 Jul from Seattle to London, returning Wed, 30 Jul, priced at ฿22,180 found 2 days ago
Delta
Sat, 2 Aug - Sat, 9 Aug
SEA
Seattle
LHR
London
฿22,710 Return, found 2 days ago
฿22,710
Return
found 2 days ago
Select Delta flight, departing Sat, 2 Aug from Seattle to London, returning Sat, 9 Aug, priced at ฿22,710 found 2 days ago
United
Sat, 9 Aug - Sun, 24 Aug
SEA
Seattle
LHR
London
฿22,885 Return, found 11 hours ago
฿22,885
Return
found 11 hours ago
Select United flight, departing Sat, 9 Aug from Seattle to London, returning Sun, 24 Aug, priced at ฿22,885 found 11 hours ago
Delta
Sat, 2 Aug - Sat, 9 Aug
SEA
Seattle
LHR
London
฿22,895 Return, found 2 days ago
฿22,895
Return
found 2 days ago
Select Delta flight, departing Sat, 2 Aug from Seattle to London, returning Sat, 9 Aug, priced at ฿22,895 found 2 days ago
Air France
Sat, 9 Aug - Sun, 24 Aug
SEA
Seattle
LHR
London
฿24,605 Return, found 11 hours ago
฿24,605
Return
found 11 hours ago
Select Air France flight, departing Sat, 9 Aug from Seattle to London, returning Sun, 24 Aug, priced at ฿24,605 found 11 hours ago
Swiss International Air Lines
Sat, 9 Aug - Sun, 24 Aug
SEA
Seattle
LHR
London
฿28,500 Return, found 11 hours ago
฿28,500
Return
found 11 hours ago
Select Swiss International Air Lines flight, departing Sat, 9 Aug from Seattle to London, returning Sun, 24 Aug, priced at ฿28,500 found 11 hours ago

Find the cheapest month to fly from Seattle (SEA) to London (LON)

April is typically the cheapest month to fly

From ฿16,433 - ฿32,330 per traveller.

Graph displaying average flight prices per month

Flight from Seattle to London route information
Origin airport
Seattle - Tacoma Intl.
Destination airport
Gatwick
Return price
฿17,875
Distance
7697 km

Perfect flights from Seattle to London

Embark on an unforgettable journey without breaking the bank with Expedia's incredible deals on cheap flights from Seattle to London. Whether you're aching for a romantic escape with your partner, craving an adventurous solo expedition, or yearning to immerse yourself in the local history and culture, we've got you covered.
 
Picture yourself strolling through the streets of , surrounded by breathtaking architecture and absorbing the vibrant atmosphere of this captivating city. Indulge in the mouth-watering local specialties, from tantalizing street food to exquisite fine dining. With Expedia, you can experience all of this and more, without sacrificing your budget.
 
Our flexible Seattle - Tacoma Intl. to LON-All Airports ticket options cater to your travel preferences, with incredible one-way fares from ฿8,965 and roundtrip prices from ฿17,875. Whether you're planning a short city break or a longer adventure, our dynamic pricing ensures that you find the best deals for your journey.
 
But the magic doesn't stop there. Expedia offers a range of partner services to enhance your trip. Rent a car at LON-All Airports and explore and its surrounding areas at your own pace. Discover hidden gems off the beaten path, and create unforgettable memories. We also provide a handpicked selection of accommodations, from charming bed and breakfasts to luxury hotels, ensuring that you have a comfortable and memorable stay.
 
Planning your next great adventure is a breeze with Expedia. Our user-friendly platform, unbeatable prices, and round-the-clock customer support are designed to make your travel experience seamless and stress-free. So, why wait? Book your to travel arrangements today and embark on the journey of a lifetime in London.

Frequently asked questions

How much is a flight from Sea-Tac Airport to London (LON-All Airports)?
Round-trip journeys from Seattle - Tacoma Intl. Airport (SEA) to London (LON-All Airports) start from ฿17,875. This is based on fares offered within the last 7 days on Expedia for flights departing within the next year --- book now so you don't miss out. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from SEA to London (LON-All Airports)?
Most flights can be cancelled online, but each air carrier has its own terms and conditions. If you do decide to cancel your flight, visit our Customer Service Portal and follow the instructions.
How do I find cheap flights from SEA to London (LON-All Airports) that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you're searching for SEA to London (LON-All Airports) flights, you'll see a "no change fees" filter for you to select.
How many hours is the flight from Seattle - Tacoma Intl. Airport (SEA) to London (LON-All Airports)?
Make the 14 hours and 48 minutes between SEA and London (LON-All Airports) as comfortable as you can. Bring the essentials, like a water bottle, toothbrush and toiletries, and simply enjoy the flight!
How far is the flight from SEA to London (LON-All Airports)?
With around 7,700 kilometres separating SEA and London (LON-All Airports), your flight will be a long one. Pack wisely and make your time on board comfortable. Simple things like an eye mask and a good travel pillow can make a massive difference.
Which airlines fly direct from Seattle - Tacoma Intl. Airport (SEA) to London (LON-All Airports)?
You have lots of options when flying from SEA to London (LON-All Airports). Lock in your fare with one of these popular airlines:

  • Virgin Atlantic - (VS) with 30 monthly flights
  • American Airlines - (AA) with 30 monthly flights
  • British Airways - (BA) with 30 monthly flights
  • Delta Air Lines - (DL) with 17 monthly flights

Are Sea-Tac Airport to London (LON-All Airports) flight tickets cheaper when they're purchased at the last minute?
Booking last minute from SEA to London (LON-All Airports) can be hit-or-miss. It is possible to score a bargain, but you could also miss out entirely! If you'd prefer to play it safe and start planning early on, Expedia compares flight deals up to 12 months in advance. Just remember that not all airlines publish their prices that far in advance. Our suggestion? Check back often as updates are made regularly.

Explore a world of travel with Expedia

London Airports

London

Seattle to Heathrow
฿18,605.00
*Available to Expedia members.