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

View AU$786 flight on Tue, 11 Nov. 2025Opens 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 for one-way flights and round trip tickets for the period specified. Prices and availability are subject to change. Additional terms apply.

Icelandair
Mon, 15 Sep. - Mon, 29 Sep.
LHR
London
SEA
Seattle
AU$901 Return, found 2 days ago
AU$901
Return
found 2 days ago
Select Icelandair flight, departing Mon, 15 Sep. from London to Seattle, returning Mon, 29 Sep., priced at AU$901 found 2 days ago
Icelandair
Fri, 5 Sep. - Sun, 21 Sep.
LHR
London
SEA
Seattle
AU$905 Return, found 2 days ago
AU$905
Return
found 2 days ago
Select Icelandair flight, departing Fri, 5 Sep. from London to Seattle, returning Sun, 21 Sep., priced at AU$905 found 2 days ago
Aer Lingus
Wed, 8 Oct. - Wed, 15 Oct.
LHR
London
SEA
Seattle
AU$969 Return, found 2 days ago
AU$969
Return
found 2 days ago
Select Aer Lingus flight, departing Wed, 8 Oct. from London to Seattle, returning Wed, 15 Oct., priced at AU$969 found 2 days ago
Scandinavian Airlines
Fri, 5 Sep. - Sun, 21 Sep.
LHR
London
SEA
Seattle
AU$989 Return, found 2 days ago
AU$989
Return
found 2 days ago
Select Scandinavian Airlines flight, departing Fri, 5 Sep. from London to Seattle, returning Sun, 21 Sep., priced at AU$989 found 2 days ago
United
Fri, 5 Sep. - Sun, 21 Sep.
LHR
London
SEA
Seattle
AU$1,002 Return, found 2 days ago
AU$1,002
Return
found 2 days ago
Select United flight, departing Fri, 5 Sep. from London to Seattle, returning Sun, 21 Sep., priced at AU$1,002 found 2 days ago
Air Canada
Sat, 6 Sep. - Mon, 22 Sep.
LHR
London
SEA
Seattle
AU$1,016 Return, found 16 hours ago
AU$1,016
Return
found 16 hours ago
Select Air Canada flight, departing Sat, 6 Sep. from London to Seattle, returning Mon, 22 Sep., priced at AU$1,016 found 16 hours ago
Delta
Wed, 8 Oct. - Wed, 15 Oct.
LHR
London
SEA
Seattle
AU$1,024 Return, found 2 days ago
AU$1,024
Return
found 2 days ago
Select Delta flight, departing Wed, 8 Oct. from London to Seattle, returning Wed, 15 Oct., priced at AU$1,024 found 2 days ago
American Airlines
Wed, 27 May - Mon, 1 Jun.
LHR
London
SEA
Seattle
AU$1,025 Return, found 2 days ago
AU$1,025
Return
found 2 days ago
Select American Airlines flight, departing Wed, 27 May from London to Seattle, returning Mon, 1 Jun., priced at AU$1,025 found 2 days ago
Swiss International Air Lines
Sat, 6 Sep. - Mon, 22 Sep.
LHR
London
SEA
Seattle
AU$1,029 Return, found 16 hours ago
AU$1,029
Return
found 16 hours ago
Select Swiss International Air Lines flight, departing Sat, 6 Sep. from London to Seattle, returning Mon, 22 Sep., priced at AU$1,029 found 16 hours ago
Lufthansa
Wed, 1 Oct. - Tue, 7 Oct.
LHR
London
SEA
Seattle
AU$1,032 Return, found 2 days ago
AU$1,032
Return
found 2 days ago
Select Lufthansa flight, departing Wed, 1 Oct. from London to Seattle, returning Tue, 7 Oct., priced at AU$1,032 found 2 days ago

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

February is typically the cheapest month to fly

From AU$751 - AU$1,490 per traveller.

Graph displaying average flight prices per month

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Flight from London to Seattle route information
Origin airport
Heathrow
Destination airport
Seattle - Tacoma Intl.
Airlines serving
Aer Lingus, Air Canada, American Airlines, British Airways, Brussels Airlines, Delta, Icelandair, KLM, Lufthansa, Swiss International Air Lines, United, Virgin Atlantic
Return price
AU$901
Distance
7657 km

Your quick guide to flights from London to Seattle

Pick up great flights from London to Seattle

With Expedia, you have your pick of flights a day with 20 airlines covering flights from London to Seattle. Whether you’re on a business trip, a family holiday or a luxury break, just enter your travel dates, hit search then check out your choice of flights. Select from return, one way or multi-city flights, and use the advance search tool if you want a direct or refundable flight. You can narrow your search to show you just your preferred cabin class and airline, too. It’s all easy. You can book direct flights from London to Seattle that take around hours.

Find cheap flights from London to Seattle

From the great flight deals with prices currently ranging from AU$901 to AU$1,424, you can choose to see the cheapest flights first. Generally, you can book the cheapest flights from London to Seattle around 4 to 6 weeks in advance. If your travel dates are flexible, try to avoid weekends and peak seasons – when you are more likely to grab the lowest prices. Even last minute, there are some impressive deals. The cheapest time to fly to Seattle is normally in September.

Reasons to book your flight from London to Seattle with Expedia

Expedia makes it easy to find, book, and travel, with everything you need all in one place. When you enter your travel details, find fantastic deals just for you on flight tickets from London to Seattle across all the main airline carriers, so you can save time, dollars, and hassle finding the perfect flight. If you think your plans could change, choose refundable flights so any changes won’t cost you more. Book your flight to Seattle right now and, if you join Expedia Rewards, you earn points this time and every time you travel with Expedia.

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 AU$901. 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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