S$510 Cheap Flights from Seattle to London

View S$510 flight on Sun, 10 Aug, 2025Opens in a new window

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

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Cheap Flights from Seattle to London (SEA-LHR)

Prices were available within the past 7 days and start at S$510 for one-way flights and S$781 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Mon, 7 Jul - Tue, 22 Jul
SEA
Seattle
LHR
London
S$781 Return, found 1 day ago
S$781
Return
found 1 day ago
Select Delta flight, departing Mon, 7 Jul from Seattle to London, returning Tue, 22 Jul, priced at S$781 found 1 day ago
Delta
Mon, 7 Jul - Tue, 22 Jul
SEA
Seattle
LHR
London
S$790 Return, found 1 day ago
S$790
Return
found 1 day ago
Select Delta flight, departing Mon, 7 Jul from Seattle to London, returning Tue, 22 Jul, priced at S$790 found 1 day ago
Virgin Atlantic
Wed, 16 Jul - Wed, 23 Jul
SEA
Seattle
LHR
London
S$790 Return, found 2 days ago
S$790
Return
found 2 days ago
Select Virgin Atlantic flight, departing Wed, 16 Jul from Seattle to London, returning Wed, 23 Jul, priced at S$790 found 2 days ago
Delta
Mon, 7 Jul - Tue, 22 Jul
SEA
Seattle
LHR
London
S$797 Return, found 1 day ago
S$797
Return
found 1 day ago
Select Delta flight, departing Mon, 7 Jul from Seattle to London, returning Tue, 22 Jul, priced at S$797 found 1 day ago
Virgin Atlantic
Mon, 7 Jul - Tue, 22 Jul
SEA
Seattle
LHR
London
S$810 Return, found 1 day ago
S$810
Return
found 1 day ago
Select Virgin Atlantic flight, departing Mon, 7 Jul from Seattle to London, returning Tue, 22 Jul, priced at S$810 found 1 day ago
United
Wed, 13 Aug - Tue, 23 Sep
SEA
Seattle
LHR
London
S$833 Return, found 6 days ago
S$833
Return
found 6 days ago
Select United flight, departing Wed, 13 Aug from Seattle to London, returning Tue, 23 Sep, priced at S$833 found 6 days ago
United
Wed, 13 Aug - Tue, 23 Sep
SEA
Seattle
LHR
London
S$841 Return, found 6 days ago
S$841
Return
found 6 days ago
Select United flight, departing Wed, 13 Aug from Seattle to London, returning Tue, 23 Sep, priced at S$841 found 6 days ago
KLM
Mon, 7 Jul - Tue, 22 Jul
SEA
Seattle
LHR
London
S$848 Return, found 1 day ago
S$848
Return
found 1 day ago
Select KLM flight, departing Mon, 7 Jul from Seattle to London, returning Tue, 22 Jul, priced at S$848 found 1 day ago
Air Canada
Wed, 13 Aug - Tue, 23 Sep
SEA
Seattle
LHR
London
S$858 Return, found 6 days ago
S$858
Return
found 6 days ago
Select Air Canada flight, departing Wed, 13 Aug from Seattle to London, returning Tue, 23 Sep, priced at S$858 found 6 days ago
Air France
Wed, 16 Jul - Wed, 23 Jul
SEA
Seattle
LHR
London
S$879 Return, found 2 days ago
S$879
Return
found 2 days ago
Select Air France flight, departing Wed, 16 Jul from Seattle to London, returning Wed, 23 Jul, priced at S$879 found 2 days ago
Seattle to London route information
Origin airport
Seattle - Tacoma Intl.
Destination airport
Heathrow
Airlines serving
Aer Lingus, Air Canada, Air France, American Airlines, Austrian Airlines, British Airways, Delta, Finnair, Iberia, KLM, Lufthansa, Turkish Airlines, United, Virgin Atlantic, WestJet
Return price
S$780
Distance
7657 km
Average flight time
17 hours 33 mins

Flights from Seattle to London

There are several airlines that operate frequent flights from Seattle (SEA) to London (LHR) including

The earliest flight leaves Seattle Tacoma Intl. Airport at 13:15 and arrives at Heathrow Airport at 06:45. The last flight of the day departs Seattle at 20:37 and arrives at London at 13:35.

The flight distance from Seattle to London is about 7743 km, the shortest flight is 09 hours with WestJet.

Expedia lets you search across the largest number of airlines and London flights, which means that you’ll be able to find a great flight deal at the perfect travel date and time. Our simple-to-use booking engine makes looking for terrific bargains easy and hassle-free; just enter your travel dates and departure city, and let Expedia do the rest! Adjust your travel dates and explore connecting flights to find an even better deal on your Seattle London flight!

Browse through dozens of options and rest assured that you’re seeing the best price guaranteed! Our friendly customer service representatives are here to serve you 24 hours day to provide assistance and answer any questions that you may have about booking your Seattle to London trip. There’s simply no substitute for great prices suited to your travel needs and backed by excellent customer support.

Combine your London flight with a hotel and/or car rental for a package deal designed to save you even more money! Discover additional savings by booking in advance or find a last minute deal. There are tons of ways to save on your flights from Seattle to London with Expedia. Use us as your stop travel destination and have the confidence that you’re getting a bargain!

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 S$781. 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.

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