S$401 Cheap Flights from Seattle to London

View S$401 flight on Sun, 23 Nov, 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$401 for one-way flights and S$851 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Thu, 6 Nov - Thu, 13 Nov
SEA
Seattle
LHR
London
S$851 Return, found 18 hours ago
S$851
Return
found 18 hours ago
Select Delta flight, departing Thu, 6 Nov from Seattle to London, returning Thu, 13 Nov, priced at S$851 found 18 hours ago
United
Thu, 6 Nov - Thu, 13 Nov
SEA
Seattle
LHR
London
S$863 Return, found 18 hours ago
S$863
Return
found 18 hours ago
Select United flight, departing Thu, 6 Nov from Seattle to London, returning Thu, 13 Nov, priced at S$863 found 18 hours ago
Virgin Atlantic
Thu, 6 Nov - Thu, 13 Nov
SEA
Seattle
LHR
London
S$884 Return, found 18 hours ago
S$884
Return
found 18 hours ago
Select Virgin Atlantic flight, departing Thu, 6 Nov from Seattle to London, returning Thu, 13 Nov, priced at S$884 found 18 hours ago
Virgin Atlantic
Thu, 6 Nov - Thu, 13 Nov
SEA
Seattle
LHR
London
S$887 Return, found 18 hours ago
S$887
Return
found 18 hours ago
Select Virgin Atlantic flight, departing Thu, 6 Nov from Seattle to London, returning Thu, 13 Nov, priced at S$887 found 18 hours ago
Air France
Thu, 6 Nov - Thu, 13 Nov
SEA
Seattle
LHR
London
S$890 Return, found 18 hours ago
S$890
Return
found 18 hours ago
Select Air France flight, departing Thu, 6 Nov from Seattle to London, returning Thu, 13 Nov, priced at S$890 found 18 hours ago
Virgin Atlantic
Thu, 6 Nov - Thu, 13 Nov
SEA
Seattle
LHR
London
S$892 Return, found 18 hours ago
S$892
Return
found 18 hours ago
Select Virgin Atlantic flight, departing Thu, 6 Nov from Seattle to London, returning Thu, 13 Nov, priced at S$892 found 18 hours ago
Virgin Atlantic
Thu, 6 Nov - Thu, 13 Nov
SEA
Seattle
LHR
London
S$895 Return, found 18 hours ago
S$895
Return
found 18 hours ago
Select Virgin Atlantic flight, departing Thu, 6 Nov from Seattle to London, returning Thu, 13 Nov, priced at S$895 found 18 hours ago
Air Canada
Thu, 6 Nov - Thu, 13 Nov
SEA
Seattle
LHR
London
S$903 Return, found 18 hours ago
S$903
Return
found 18 hours ago
Select Air Canada flight, departing Thu, 6 Nov from Seattle to London, returning Thu, 13 Nov, priced at S$903 found 18 hours ago
Lufthansa
Thu, 6 Nov - Thu, 13 Nov
SEA
Seattle
LHR
London
S$912 Return, found 18 hours ago
S$912
Return
found 18 hours ago
Select Lufthansa flight, departing Thu, 6 Nov from Seattle to London, returning Thu, 13 Nov, priced at S$912 found 18 hours ago
Lufthansa
Thu, 6 Nov - Thu, 13 Nov
SEA
Seattle
LHR
London
S$913 Return, found 18 hours ago
S$913
Return
found 18 hours ago
Select Lufthansa flight, departing Thu, 6 Nov from Seattle to London, returning Thu, 13 Nov, priced at S$913 found 18 hours ago

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

October is typically the cheapest month to fly

From S$617 - S$1,334 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 S$851. 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

Travel information

Origin airport
Seattle - Tacoma Intl.
Destination airport
Heathrow
Airlines serving
Air Canada, Air France, American Airlines, Austrian Airlines, British Airways, Delta, Finnair, Iberia, KLM, Lufthansa, Singapore Airlines, Turkish Airlines, United, Virgin Atlantic, WestJet
Return price
S$850
Distance
7657 km
Average flight time
17 hours 33 mins

Book with confidence

Book with confidence

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!

Flights from Seattle to London

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