฿18,560 Cheap Flights from London (LHR) to Seattle (SEA)

View ฿18,560 flight on Thu, 10 Sept 2026Opens in a new window

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

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

Prices were available within the past 7 days and start at ฿18,560 for one-way flights and ฿23,070 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Icelandair
Fri, 29 May - Mon, 1 Jun
LHR
London
SEA
Seattle
฿23,070 Return, found 6 days ago
฿23,070
Return
found 6 days ago
Select Icelandair flight, departing Fri, 29 May from London to Seattle, returning Mon, 1 Jun, priced at ฿23,070 found 6 days ago
Icelandair
Sat, 6 Jun - Mon, 22 Jun
LHR
London
SEA
Seattle
฿24,235 Return, found 12 hours ago
฿24,235
Return
found 12 hours ago
Select Icelandair flight, departing Sat, 6 Jun from London to Seattle, returning Mon, 22 Jun, priced at ฿24,235 found 12 hours ago
Delta
Sat, 6 Jun - Mon, 22 Jun
LHR
London
SEA
Seattle
฿28,085 Return, found 12 hours ago
฿28,085
Return
found 12 hours ago
Select Delta flight, departing Sat, 6 Jun from London to Seattle, returning Mon, 22 Jun, priced at ฿28,085 found 12 hours ago
Delta
Sat, 6 Jun - Mon, 22 Jun
LHR
London
SEA
Seattle
฿28,325 Return, found 12 hours ago
฿28,325
Return
found 12 hours ago
Select Delta flight, departing Sat, 6 Jun from London to Seattle, returning Mon, 22 Jun, priced at ฿28,325 found 12 hours ago
Delta
Sat, 6 Jun - Mon, 22 Jun
LHR
London
SEA
Seattle
฿29,430 Return, found 12 hours ago
฿29,430
Return
found 12 hours ago
Select Delta flight, departing Sat, 6 Jun from London to Seattle, returning Mon, 22 Jun, priced at ฿29,430 found 12 hours ago
Delta
Sat, 6 Jun - Mon, 22 Jun
LHR
London
SEA
Seattle
฿30,035 Return, found 12 hours ago
฿30,035
Return
found 12 hours ago
Select Delta flight, departing Sat, 6 Jun from London to Seattle, returning Mon, 22 Jun, priced at ฿30,035 found 12 hours ago
Air France
Sat, 6 Jun - Mon, 22 Jun
LHR
London
SEA
Seattle
฿31,220 Return, found 12 hours ago
฿31,220
Return
found 12 hours ago
Select Air France flight, departing Sat, 6 Jun from London to Seattle, returning Mon, 22 Jun, priced at ฿31,220 found 12 hours ago
KLM
Sat, 6 Jun - Mon, 22 Jun
LHR
London
SEA
Seattle
฿31,320 Return, found 12 hours ago
฿31,320
Return
found 12 hours ago
Select KLM flight, departing Sat, 6 Jun from London to Seattle, returning Mon, 22 Jun, priced at ฿31,320 found 12 hours ago
Scandinavian Airlines
Fri, 10 Jul - Sat, 3 Oct
LHR
London
SEA
Seattle
฿32,010 Return, found 4 days ago
฿32,010
Return
found 4 days ago
Select Scandinavian Airlines flight, departing Fri, 10 Jul from London to Seattle, returning Sat, 3 Oct, priced at ฿32,010 found 4 days ago
Air Canada
Fri, 10 Jul - Sat, 3 Oct
LHR
London
SEA
Seattle
฿33,560 Return, found 4 days ago
฿33,560
Return
found 4 days ago
Select Air Canada flight, departing Fri, 10 Jul from London to Seattle, returning Sat, 3 Oct, priced at ฿33,560 found 4 days ago

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

April is typically the cheapest month to fly

From ฿20,942 - ฿37,422 per traveller.

Frequently asked questions

How much is a flight from Heathrow Airport to Sea-Tac Airport?
Start packing your bags, because round-trip journeys from LHR to Seattle - Tacoma Intl. Airport (SEA) start from ฿23,070. That's based on airfares listed within the last 7 days on Expedia for flights departing within the next year. Prices can change quickly, so book now to secure the best deal. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from Heathrow Airport (LHR) to Sea-Tac Airport?
Most flights can be cancelled online, but whether you incur a fee depends on your airline. If you do have to cancel your trip, follow the instructions in the Customer Service Portal.
How do I find cheap flights from Heathrow Airport to SEA 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 London Heathrow to Sea-Tac Airport flights, you'll see a "no change fees" filter for you to select.
How far is the flight from Heathrow Airport (LHR) to Seattle - Tacoma Intl. Airport (SEA)?
With around 7,700 kilometres separating LHR and Seattle - Tacoma Intl. Airport (SEA), your flight will be a long one. Pack wisely to make your time on board more comfortable. Little things like an extra pair of socks and a good neck pillow can make a big difference.
Which airlines fly direct from Heathrow Airport to Sea-Tac Airport?
Getting from London Heathrow to Sea-Tac Airport is easy when you have a good range of airlines to choose from. Here are a few of the best:

  • 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 Heathrow Airport to Sea-Tac Airport flight tickets cheaper when they're purchased at the last minute?
Late planners can sometimes score a bargain, with some of the cheapest airfares from London Heathrow to SEA surfacing a few weeks before the departure date. If you'd rather book ahead, Expedia compares and updates all the best flight deals continuously — as early as a year in advance in some cases. It depends on the carrier though, as not all airlines advertise prices that far in advance.

Travel information

Origin airport
Heathrow
Destination airport
Seattle - Tacoma Intl.
Return price
฿23,070
Distance
7657 km
Average flight time
2 hours 6 mins

Book with confidence

Perfect flights from London to Seattle

Embark on an unforgettable journey without breaking the bank with Expedia's incredible deals on cheap flights from London to Seattle. 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 Heathrow to Seattle - Tacoma Intl. ticket options cater to your travel preferences, with incredible one-way fares from ฿18,560 and roundtrip prices from ฿23,070. 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 Seattle - Tacoma Intl. 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 Seattle.
Perfect flights from London to Seattle
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