S$542 Cheap Flights from Seattle to London

View S$542 flight on Wed, 15 Oct, 2025Opens in a new window

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

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Cheap Flights from Seattle to London (SEA-LON)

Prices were available within the past 7 days and start at S$542 for one-way flights and S$906 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Sun, 5 Oct - Tue, 14 Oct
SEA
Seattle
LHR
London
S$906 Return, found 10 hours ago
S$906
Return
found 10 hours ago
Select United flight, departing Sun, 5 Oct from Seattle to London, returning Tue, 14 Oct, priced at S$906 found 10 hours ago
Virgin Atlantic
Mon, 17 Nov - Wed, 26 Nov
SEA
Seattle
LHR
London
S$913 Return, found 6 days ago
S$913
Return
found 6 days ago
Select Virgin Atlantic flight, departing Mon, 17 Nov from Seattle to London, returning Wed, 26 Nov, priced at S$913 found 6 days ago
Delta
Mon, 17 Nov - Wed, 26 Nov
SEA
Seattle
LHR
London
S$913 Return, found 6 days ago
S$913
Return
found 6 days ago
Select Delta flight, departing Mon, 17 Nov from Seattle to London, returning Wed, 26 Nov, priced at S$913 found 6 days ago
Air Canada
Mon, 6 Oct - Wed, 15 Oct
SEA
Seattle
LHR
London
S$914 Return, found 6 days ago
S$914
Return
found 6 days ago
Select Air Canada flight, departing Mon, 6 Oct from Seattle to London, returning Wed, 15 Oct, priced at S$914 found 6 days ago
Virgin Atlantic
Sun, 5 Oct - Tue, 14 Oct
SEA
Seattle
LHR
London
S$922 Return, found 10 hours ago
S$922
Return
found 10 hours ago
Select Virgin Atlantic flight, departing Sun, 5 Oct from Seattle to London, returning Tue, 14 Oct, priced at S$922 found 10 hours ago
Air Canada
Mon, 17 Nov - Wed, 26 Nov
SEA
Seattle
LHR
London
S$923 Return, found 6 days ago
S$923
Return
found 6 days ago
Select Air Canada flight, departing Mon, 17 Nov from Seattle to London, returning Wed, 26 Nov, priced at S$923 found 6 days ago
Swiss International Air Lines
Mon, 17 Nov - Wed, 26 Nov
SEA
Seattle
LGW
London
S$927 Return, found 6 days ago
S$927
Return
found 6 days ago
Select Swiss International Air Lines flight, departing Mon, 17 Nov from Seattle to London, returning Wed, 26 Nov, priced at S$927 found 6 days ago
Lufthansa
Sun, 5 Oct - Tue, 14 Oct
SEA
Seattle
LHR
London
S$931 Return, found 10 hours ago
S$931
Return
found 10 hours ago
Select Lufthansa flight, departing Sun, 5 Oct from Seattle to London, returning Tue, 14 Oct, priced at S$931 found 10 hours ago
British Airways
Sun, 5 Oct - Tue, 14 Oct
SEA
Seattle
LHR
London
S$958 Return, found 10 hours ago
S$958
Return
found 10 hours ago
Select British Airways flight, departing Sun, 5 Oct from Seattle to London, returning Tue, 14 Oct, priced at S$958 found 10 hours ago
KLM
Mon, 17 Nov - Wed, 26 Nov
SEA
Seattle
LHR
London
S$973 Return, found 6 days ago
S$973
Return
found 6 days ago
Select KLM flight, departing Mon, 17 Nov from Seattle to London, returning Wed, 26 Nov, priced at S$973 found 6 days ago

Frequently asked questions

How much is a flight from Sea-Tac Airport to London (LON-All Airports)?
Round-trip journeys from Seattle - Tacoma Intl. Airport (SEA) to London (LON-All Airports) start from S$906. This is based on fares offered within the last 7 days on Expedia for flights departing within the next year — book now so you don’t miss out. 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 London (LON-All Airports)?
Most flights can be cancelled online, but each air carrier has its own terms and conditions. If you do decide to cancel your flight, visit our Customer Service Portal and follow the instructions.
How do I find cheap flights from SEA to London (LON-All Airports) 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 SEA to London (LON-All Airports) flights, you’ll see a “no change fees” filter for you to select.
How many hours is the flight from Seattle - Tacoma Intl. Airport (SEA) to London (LON-All Airports)?
Make the 14 hours and 48 minutes between SEA and London (LON-All Airports) as comfortable as you can. Bring the essentials, like a water bottle, toothbrush and toiletries, and simply enjoy the flight!
How far is the flight from SEA to London (LON-All Airports)?
With around 7,700 kilometres separating SEA and London (LON-All Airports), your flight will be a long one. Pack wisely and make your time on board comfortable. Simple things like an eye mask and a good travel pillow can make a massive difference.
Which airlines fly direct from Seattle - Tacoma Intl. Airport (SEA) to London (LON-All Airports)?
You have lots of options when flying from SEA to London (LON-All Airports). Lock in your fare with one of these popular airlines:

  • 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-Tac Airport to London (LON-All Airports) flight tickets cheaper when they're purchased at the last minute?
Booking last minute from SEA to London (LON-All Airports) can be hit-or-miss. It is possible to score a bargain, but you could also miss out entirely! If you’d prefer to play it safe and start planning early on, Expedia compares flight deals up to 12 months in advance. Just remember that not all airlines publish their prices that far in advance. Our suggestion? Check back often as updates are made regularly.
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