฿13,040 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 ฿13,040 for one-way flights and ฿28,380 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Turkish Airlines
Thu, 23 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿28,380 Return, found 2 days ago
฿28,380
Return
found 2 days ago
Select Turkish Airlines flight, departing Thu, 23 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿28,380 found 2 days ago
Delta
Thu, 23 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿29,040 Return, found 2 days ago
฿29,040
Return
found 2 days ago
Select Delta flight, departing Thu, 23 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿29,040 found 2 days ago
Icelandair
Thu, 23 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿29,290 Return, found 2 days ago
฿29,290
Return
found 2 days ago
Select Icelandair flight, departing Thu, 23 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿29,290 found 2 days ago
Delta
Thu, 23 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿29,815 Return, found 2 days ago
฿29,815
Return
found 2 days ago
Select Delta flight, departing Thu, 23 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿29,815 found 2 days ago
Icelandair
Thu, 23 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿29,885 Return, found 2 days ago
฿29,885
Return
found 2 days ago
Select Icelandair flight, departing Thu, 23 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿29,885 found 2 days ago
British Airways
Thu, 23 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿29,915 Return, found 2 days ago
฿29,915
Return
found 2 days ago
Select British Airways flight, departing Thu, 23 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿29,915 found 2 days ago
Air France
Thu, 23 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿29,920 Return, found 2 days ago
฿29,920
Return
found 2 days ago
Select Air France flight, departing Thu, 23 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿29,920 found 2 days ago
Air Canada
Thu, 23 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿30,470 Return, found 2 days ago
฿30,470
Return
found 2 days ago
Select Air Canada flight, departing Thu, 23 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿30,470 found 2 days ago
KLM
Thu, 23 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿30,695 Return, found 2 days ago
฿30,695
Return
found 2 days ago
Select KLM flight, departing Thu, 23 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿30,695 found 2 days ago
Air Canada
Thu, 23 Apr - Sun, 26 Apr
SEA
Seattle
LHR
London
฿30,730 Return, found 2 days ago
฿30,730
Return
found 2 days ago
Select Air Canada flight, departing Thu, 23 Apr from Seattle to London, returning Sun, 26 Apr, priced at ฿30,730 found 2 days ago

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

October is typically the cheapest month to fly

From ฿15,411 - ฿27,225 per traveller.

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 ฿28,380. 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.

Travel information

Origin airport
Seattle - Tacoma Intl.
Destination airport
Heathrow
Return price
฿28,380
Distance
7657 km
Average flight time
16 hours 36 mins

Book with confidence

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 ฿13,040 and roundtrip prices from ฿28,380. 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.
Perfect flights from Seattle to London
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