฿17,435 Cheap Flights from London (LHR) to Seattle (SEA)

View ฿17,435 flight on Thu, 8 Jan 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 ฿17,435 for one-way flights and ฿21,125 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Icelandair
Wed, 19 Nov - Wed, 3 Dec
LHR
London
SEA
Seattle
฿21,125 Return, found 6 days ago
฿21,125
Return
found 6 days ago
Select Icelandair flight, departing Wed, 19 Nov from London to Seattle, returning Wed, 3 Dec, priced at ฿21,125 found 6 days ago
Air Canada
Wed, 19 Nov - Wed, 3 Dec
LHR
London
SEA
Seattle
฿21,735 Return, found 6 days ago
฿21,735
Return
found 6 days ago
Select Air Canada flight, departing Wed, 19 Nov from London to Seattle, returning Wed, 3 Dec, priced at ฿21,735 found 6 days ago
Air Canada
Wed, 19 Nov - Wed, 3 Dec
LHR
London
SEA
Seattle
฿21,950 Return, found 6 days ago
฿21,950
Return
found 6 days ago
Select Air Canada flight, departing Wed, 19 Nov from London to Seattle, returning Wed, 3 Dec, priced at ฿21,950 found 6 days ago
Icelandair
Wed, 19 Nov - Wed, 26 Nov
LHR
London
SEA
Seattle
฿22,280 Return, found 6 days ago
฿22,280
Return
found 6 days ago
Select Icelandair flight, departing Wed, 19 Nov from London to Seattle, returning Wed, 26 Nov, priced at ฿22,280 found 6 days ago
United
Wed, 19 Nov - Wed, 3 Dec
LHR
London
SEA
Seattle
฿22,670 Return, found 6 days ago
฿22,670
Return
found 6 days ago
Select United flight, departing Wed, 19 Nov from London to Seattle, returning Wed, 3 Dec, priced at ฿22,670 found 6 days ago
Lufthansa
Wed, 19 Nov - Wed, 3 Dec
LHR
London
SEA
Seattle
฿22,755 Return, found 6 days ago
฿22,755
Return
found 6 days ago
Select Lufthansa flight, departing Wed, 19 Nov from London to Seattle, returning Wed, 3 Dec, priced at ฿22,755 found 6 days ago
United
Wed, 19 Nov - Wed, 3 Dec
LHR
London
SEA
Seattle
฿22,870 Return, found 6 days ago
฿22,870
Return
found 6 days ago
Select United flight, departing Wed, 19 Nov from London to Seattle, returning Wed, 3 Dec, priced at ฿22,870 found 6 days ago
Lufthansa
Wed, 19 Nov - Wed, 3 Dec
LHR
London
SEA
Seattle
฿22,885 Return, found 6 days ago
฿22,885
Return
found 6 days ago
Select Lufthansa flight, departing Wed, 19 Nov from London to Seattle, returning Wed, 3 Dec, priced at ฿22,885 found 6 days ago
Delta
Thu, 20 Nov - Thu, 27 Nov
LHR
London
SEA
Seattle
฿23,210 Return, found 22 hours ago
฿23,210
Return
found 22 hours ago
Select Delta flight, departing Thu, 20 Nov from London to Seattle, returning Thu, 27 Nov, priced at ฿23,210 found 22 hours ago
Lufthansa
Wed, 19 Nov - Wed, 3 Dec
LHR
London
SEA
Seattle
฿23,395 Return, found 6 days ago
฿23,395
Return
found 6 days ago
Select Lufthansa flight, departing Wed, 19 Nov from London to Seattle, returning Wed, 3 Dec, priced at ฿23,395 found 6 days ago

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

February is typically the cheapest month to fly

From ฿15,786 - ฿31,293 per traveller.
Flight from London to Seattle route information
Origin airport
Heathrow
Destination airport
Seattle - Tacoma Intl.
Airlines serving
Air Canada, Air France, American Airlines, Austrian Airlines, British Airways, Delta, Finnair, Iberia, KLM, Lufthansa, Turkish Airlines, United, WestJet
Return price
฿21,125
Distance
7657 km
Average flight time
2 hours 1 min

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 ฿17,435 and roundtrip prices from ฿21,125. 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.

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 ฿21,125. 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.

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