฿12,295 Cheap Flights from Seattle (SEA) to London (LHR)

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

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

Prices were available within the past 7 days and start at ฿12,295 for one-way flights and ฿21,045 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Air Canada
Thu, 12 Feb - Fri, 27 Feb
SEA
Seattle
LHR
London
฿21,045 Return, found 2 days ago
฿21,045
Return
found 2 days ago
Select Air Canada flight, departing Thu, 12 Feb from Seattle to London, returning Fri, 27 Feb, priced at ฿21,045 found 2 days ago
Air Canada
Thu, 12 Feb - Fri, 27 Feb
SEA
Seattle
LHR
London
฿21,305 Return, found 2 days ago
฿21,305
Return
found 2 days ago
Select Air Canada flight, departing Thu, 12 Feb from Seattle to London, returning Fri, 27 Feb, priced at ฿21,305 found 2 days ago
Air Canada
Thu, 23 Apr - Fri, 8 May
SEA
Seattle
LHR
London
฿21,550 Return, found 14 hours ago
฿21,550
Return
found 14 hours ago
Select Air Canada flight, departing Thu, 23 Apr from Seattle to London, returning Fri, 8 May, priced at ฿21,550 found 14 hours ago
Lufthansa
Thu, 12 Feb - Fri, 27 Feb
SEA
Seattle
LHR
London
฿21,710 Return, found 2 days ago
฿21,710
Return
found 2 days ago
Select Lufthansa flight, departing Thu, 12 Feb from Seattle to London, returning Fri, 27 Feb, priced at ฿21,710 found 2 days ago
Air Canada
Thu, 23 Apr - Fri, 8 May
SEA
Seattle
LHR
London
฿21,810 Return, found 14 hours ago
฿21,810
Return
found 14 hours ago
Select Air Canada flight, departing Thu, 23 Apr from Seattle to London, returning Fri, 8 May, priced at ฿21,810 found 14 hours ago
Air Canada
Sat, 4 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿21,895 Return, found 7 hours ago
฿21,895
Return
found 7 hours ago
Select Air Canada flight, departing Sat, 4 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿21,895 found 7 hours ago
British Airways
Thu, 23 Apr - Fri, 8 May
SEA
Seattle
LHR
London
฿21,960 Return, found 14 hours ago
฿21,960
Return
found 14 hours ago
Select British Airways flight, departing Thu, 23 Apr from Seattle to London, returning Fri, 8 May, priced at ฿21,960 found 14 hours ago
Delta
Thu, 23 Apr - Fri, 8 May
SEA
Seattle
LHR
London
฿22,445 Return, found 14 hours ago
฿22,445
Return
found 14 hours ago
Select Delta flight, departing Thu, 23 Apr from Seattle to London, returning Fri, 8 May, priced at ฿22,445 found 14 hours ago
United
Sun, 5 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿22,445 Return, found 7 hours ago
฿22,445
Return
found 7 hours ago
Select United flight, departing Sun, 5 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿22,445 found 7 hours ago
Delta
Thu, 23 Apr - Fri, 8 May
SEA
Seattle
LHR
London
฿22,445 Return, found 14 hours ago
฿22,445
Return
found 14 hours ago
Select Delta flight, departing Thu, 23 Apr from Seattle to London, returning Fri, 8 May, priced at ฿22,445 found 14 hours ago
Flight from Seattle to London route information
Origin airport
Seattle - Tacoma Intl.
Destination airport
Heathrow
Return price
฿21,045
Distance
7657 km
Average flight time
17 hours 35 mins

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 Heathrow ticket options cater to your travel preferences, with incredible one-way fares from ฿12,295 and roundtrip prices from ฿21,045. 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 Heathrow 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 Heathrow Airport (LHR)?
If you're travelling between SEA and London Heathrow, round-trip journeys start from ฿21,045. This price is based on fares listed within the last 7 days on Expedia for flights departing within the next year, so don't delay. Book today and save yourself money and time. 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 Heathrow Airport?
The majority of flights can be cancelled online, but whether you are charged a fee all comes down to your airline. If you do need to cancel your trip, follow the instructions in the Customer Service Portal.
How do I find cheap flights from Seattle - Tacoma Intl. Airport (SEA) to LHR 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 Seattle - Tacoma Intl. Airport (SEA) to London Heathrow flights, you'll see a "no change fees" filter for you to select.
How far is the flight from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport?
With a flight distance of 7,700 kilometres between Sea-Tac Airport and Heathrow Airport (LHR), this is a long trip. Be sure to drink plenty of water and go for a short walk down the aisle every now and then.
Which airlines fly direct from SEA to Heathrow Airport (LHR)?
It's easy to fly directly from Sea-Tac Airport to Heathrow Airport. Below are the most sought-after carriers that offer nonstop services on this route:

  • 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 to LHR flight tickets cheaper when they're purchased at the last minute?
Flight prices are constantly going up and down, so there are no guarantees. While last-minute deals between Seattle - Tacoma Intl. Airport (SEA) and Heathrow Airport are of course possible, it's also a good idea to keep track of prices well before you fly. In fact, some airlines announce their prices up to a year prior to the departure date. Expedia is constantly updating the best bargains around, so keep checking back and be ready to lock in your seat when the price dips.
*Available to Expedia members.