฿17,965 Cheap Flights from London (LHR) to Seattle (SEA)

View ฿17,965 flight on Wed, 7 Oct 2026Opens in a new window

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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 ฿17,965 for one-way flights and ฿18,020 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Icelandair
Wed, 7 Oct - Wed, 21 Oct
LHR
London
SEA
Seattle
฿18,020 Return, found 4 days ago
฿18,020
Return
found 4 days ago
Select Icelandair flight, departing Wed, 7 Oct from London to Seattle, returning Wed, 21 Oct, priced at ฿18,020 found 4 days ago
Icelandair
Wed, 14 Oct - Wed, 28 Oct
LHR
London
SEA
Seattle
฿18,345 Return, found 1 hour ago
฿18,345
Return
found 1 hour ago
Select Icelandair flight, departing Wed, 14 Oct from London to Seattle, returning Wed, 28 Oct, priced at ฿18,345 found 1 hour ago
Icelandair
Thu, 23 Jul - Thu, 30 Jul
LHR
London
SEA
Seattle
฿19,410 Return, found 4 days ago
฿19,410
Return
found 4 days ago
Select Icelandair flight, departing Thu, 23 Jul from London to Seattle, returning Thu, 30 Jul, priced at ฿19,410 found 4 days ago
Finnair
Wed, 14 Oct - Wed, 28 Oct
LHR
London
SEA
Seattle
฿21,670 Return, found 1 hour ago
฿21,670
Return
found 1 hour ago
Select Finnair flight, departing Wed, 14 Oct from London to Seattle, returning Wed, 28 Oct, priced at ฿21,670 found 1 hour ago
American Airlines
Wed, 14 Oct - Wed, 28 Oct
LHR
London
SEA
Seattle
฿21,675 Return, found 1 hour ago
฿21,675
Return
found 1 hour ago
Select American Airlines flight, departing Wed, 14 Oct from London to Seattle, returning Wed, 28 Oct, priced at ฿21,675 found 1 hour ago
British Airways
Wed, 7 Oct - Wed, 21 Oct
LHR
London
SEA
Seattle
฿21,680 Return, found 4 days ago
฿21,680
Return
found 4 days ago
Select British Airways flight, departing Wed, 7 Oct from London to Seattle, returning Wed, 21 Oct, priced at ฿21,680 found 4 days ago
Air Canada
Wed, 14 Oct - Wed, 28 Oct
LHR
London
SEA
Seattle
฿21,810 Return, found 1 hour ago
฿21,810
Return
found 1 hour ago
Select Air Canada flight, departing Wed, 14 Oct from London to Seattle, returning Wed, 28 Oct, priced at ฿21,810 found 1 hour ago
American Airlines
Wed, 14 Oct - Wed, 28 Oct
LHR
London
SEA
Seattle
฿21,860 Return, found 1 hour ago
฿21,860
Return
found 1 hour ago
Select American Airlines flight, departing Wed, 14 Oct from London to Seattle, returning Wed, 28 Oct, priced at ฿21,860 found 1 hour ago
British Airways
Wed, 7 Oct - Wed, 21 Oct
LHR
London
SEA
Seattle
฿22,255 Return, found 4 days ago
฿22,255
Return
found 4 days ago
Select British Airways flight, departing Wed, 7 Oct from London to Seattle, returning Wed, 21 Oct, priced at ฿22,255 found 4 days ago
United
Thu, 25 Jun - Thu, 2 Jul
LHR
London
SEA
Seattle
฿22,985 Return, found 4 days ago
฿22,985
Return
found 4 days ago
Select United flight, departing Thu, 25 Jun from London to Seattle, returning Thu, 2 Jul, priced at ฿22,985 found 4 days ago

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

November is typically the cheapest month to fly

From ฿20,776 - ฿27,092 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 ฿18,020. 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

0
Origin airport
Heathrow
Destination airport
Seattle - Tacoma Intl.
Return price
฿18,020
Distance
7657 km

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 ฿17,965 and roundtrip prices from ฿18,020. 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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