$245 Cheap Flights from Seattle (SEA) to London (LHR)

View $245 flight on Wed, Feb 25, 2026Opens in a new window

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

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Today's featured flight deals from Seattle-Tacoma International Airport (SEA) to Heathrow Airport (LHR)

Nonstop
Carry-on included
Lower price than typical

Cheap Flights from Seattle to London (SEA-LHR)

Prices were available within the past 7 days and start at $245 for one-way flights and $401 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Icelandair
Sun, Apr 5 - Sat, Apr 18
SEA
Seattle
LHR
London
$401 Roundtrip, found 1 hour ago
$401
Roundtrip
found 1 hour ago
Select Icelandair flight, departing Sun, Apr 5 from Seattle to London, returning Sat, Apr 18, priced at $401 found 1 hour ago
Aer Lingus
Wed, Oct 15 - Wed, Oct 29
SEA
Seattle
LHR
London
$482 Roundtrip, found 11 hours ago
$482
Roundtrip
found 11 hours ago
Select Aer Lingus flight, departing Wed, Oct 15 from Seattle to London, returning Wed, Oct 29, priced at $482 found 11 hours ago
Lufthansa
Tue, Jan 20 - Fri, Jan 30
SEA
Seattle
LHR
London
$502 Roundtrip, found 7 hours ago
$502
Roundtrip
found 7 hours ago
Select Lufthansa flight, departing Tue, Jan 20 from Seattle to London, returning Fri, Jan 30, priced at $502 found 7 hours ago
Air Canada
Tue, Jan 20 - Fri, Jan 30
SEA
Seattle
LHR
London
$516 Roundtrip, found 7 hours ago
$516
Roundtrip
found 7 hours ago
Select Air Canada flight, departing Tue, Jan 20 from Seattle to London, returning Fri, Jan 30, priced at $516 found 7 hours ago
Iberia
Tue, Jan 20 - Fri, Jan 30
SEA
Seattle
LHR
London
$531 Roundtrip, found 7 hours ago
$531
Roundtrip
found 7 hours ago
Select Iberia flight, departing Tue, Jan 20 from Seattle to London, returning Fri, Jan 30, priced at $531 found 7 hours ago
British Airways
Tue, Jan 20 - Fri, Jan 30
SEA
Seattle
LHR
London
$554 Roundtrip, found 7 hours ago
$554
Roundtrip
found 7 hours ago
Select British Airways flight, departing Tue, Jan 20 from Seattle to London, returning Fri, Jan 30, priced at $554 found 7 hours ago
United
Sun, Apr 5 - Sat, Apr 18
SEA
Seattle
LHR
London
$560 Roundtrip, found 1 hour ago
$560
Roundtrip
found 1 hour ago
Select United flight, departing Sun, Apr 5 from Seattle to London, returning Sat, Apr 18, priced at $560 found 1 hour ago
American Airlines
Sun, Apr 5 - Sat, Apr 18
SEA
Seattle
LHR
London
$570 Roundtrip, found 1 hour ago
$570
Roundtrip
found 1 hour ago
Select American Airlines flight, departing Sun, Apr 5 from Seattle to London, returning Sat, Apr 18, priced at $570 found 1 hour ago
Virgin Atlantic
Sun, Apr 5 - Sat, Apr 18
SEA
Seattle
LHR
London
$574 Roundtrip, found 1 hour ago
$574
Roundtrip
found 1 hour ago
Select Virgin Atlantic flight, departing Sun, Apr 5 from Seattle to London, returning Sat, Apr 18, priced at $574 found 1 hour ago
Delta
Sun, Apr 5 - Sat, Apr 18
SEA
Seattle
LHR
London
$574 Roundtrip, found 1 hour ago
$574
Roundtrip
found 1 hour ago
Select Delta flight, departing Sun, Apr 5 from Seattle to London, returning Sat, Apr 18, priced at $574 found 1 hour ago

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

October is typically the cheapest month to fly

From $478 - $960 per traveler.

Frequently asked questions

How much does a flight from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR) cost?
Grab a cheap one-way flight from $245 or cheap return flight from $401 from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight deals on this route.
What is the cheapest month to fly from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR)?
April is the least expensive month to fly from SEA to LHR. Planning your trip for the off-season is often the key to landing a great deal.
Which airlines fly direct from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR)?
Fly straight to Heathrow Airport (LHR). 3 carriers operate direct flights from Seattle - Tacoma Intl. Airport (SEA), including:

  • British Airways
  • Virgin Atlantic
  • Delta Air Lines

What is the cheapest airline that flies from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR)?
Delta Air Lines and Virgin Atlantic are some popular carriers offering reasonable fares. Remember that flight prices from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR) can vary depending on demand, travel dates and how early you book. With Expedia's search tool, you can easily find a SEA to LHR flight that fits your preferences and budget.
How many flights per day from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR)?
When taking off from Seattle - Tacoma Intl. Airport (SEA), you'll have your pick from an average of 2 daily nonstop flights to Heathrow Airport (LHR).
What are the most popular departure times for flights from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR)?
More people fly between SEA and LHR at 5 PM than at any other point in the day. Looking for a quieter experience? Consider flying outside peak hours and you're likely to save on your fare as well.
What day of the week has the most flights from SEA to LHR?
If you travel on a Friday, you'll get the greatest range of options for flights from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR).
What is the earliest flight from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR)?
The first flight of the day departing from Seattle - Tacoma Intl. Airport (SEA) is at around 1:35PM UTC-8. Catch this flight and you'll land at Heathrow Airport (LHR) at approximately 7:00AM UTC+0. The entire trip takes 9h 25m.
How long does it take to fly from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR)?
Flights from SEA to LHR have an average travel time of 9 hours and 25 minutes. The distance between the two airports is 4,800 mi.
What airline has the least delays from SEA to LHR?
With 80% of flights generally landing on schedule, American Airlines has the best on-time performance for nonstop flights from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR). To keep track of your flight status and get notified if anything changes, head to the Expedia App.
What is the best time to fly from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR)?
To land at Heathrow Airport (LHR) without delays, book a flight that takes off from Seattle - Tacoma Intl. Airport (SEA) before 3 PM. The chance of cancellations is 22% higher, on average, for departures after this time.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports do you fly into for London from Seattle - Tacoma Intl. Airport (SEA)?
If you're taking a direct flight from Seattle - Tacoma Intl. Airport (SEA) to London, Heathrow Airport (LHR) is the only airport you can land at.
Is it cheaper to buy a plane ticket from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR) last-minute?
Booking your ticket from SEA to LHR right before your journey is typically more expensive. But if there's some wiggle room with your departure times and dates, you could land a cheap last-minute fare.
Is it cheaper to book a SEA to LHR flight and hotel package?
Booking a SEA to LHR flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the convenience of organizing your trip all in one place. Select from our extensive range of accommodations and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR)?
In most cases, you can cancel or reschedule your SEA to LHR flight. However, additional fees may apply, especially if your booking was made over 24 hours ago. Check your itinerary for the airline's fees and guidelines on flight changes, or if you'd like further information, head to our Customer Service portal.

Travel information

Travel information

Origin airport
Seattle - Tacoma Intl.
Destination airport
Heathrow
Airlines serving
Aer Lingus, Air Canada, Air France, Alaska Airlines, American Airlines, Austrian Airlines, British Airways, Brussels Airlines, Delta, Finnair, Iberia, Icelandair, JetBlue Airways, KLM, Lufthansa, Scandinavian Airlines, Turkish Airlines, United, Virgin Atlantic, WestJet
Roundtrip price
$401
Distance
4786 mi
Average flight time
17 hours 33 mins

Book with confidence

Book with confidence

Seattle to London Flights

The cheapest times to fly from Seattle to London

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Seattle to London are during the month of April. You can find some of the cheapest flights from Seattle to London with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Seattle to London

Sunday is one of the best days to book for cheap flights from Seattle to London: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Seattle to London

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Seattle to London in 2025. You can also book with separate airlines for your outbound and return journeys, from $245 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Seattle to London flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Seattle to London airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Seattle to London Flights

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