CA $573 Cheap Flights from Seattle (SEA) to London (LHR)

View CA $573 flight on Wed, Feb 10, 2027Opens in a new window

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 CA $573 for one-way flights and CA $909 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Scandinavian Airlines
Fri, Oct 2 - Sun, Oct 4
SEA
Seattle
LHR
London
CA $909 Roundtrip, found 1 day ago
CA $909
Roundtrip
found 1 day ago
Select Scandinavian Airlines flight, departing Fri, Oct 2 from Seattle to London, returning Sun, Oct 4, priced at CA $909 found 1 day ago
Delta
Mon, Sep 7 - Wed, Sep 9
SEA
Seattle
LHR
London
CA $1,120 Roundtrip, found 19 hours ago
CA $1,120
Roundtrip
found 19 hours ago
Select Delta flight, departing Mon, Sep 7 from Seattle to London, returning Wed, Sep 9, priced at CA $1,120 found 19 hours ago
Icelandair
Tue, Nov 10 - Tue, Nov 24
SEA
Seattle
LHR
London
CA $1,149 Roundtrip, found 5 days ago
CA $1,149
Roundtrip
found 5 days ago
Select Icelandair flight, departing Tue, Nov 10 from Seattle to London, returning Tue, Nov 24, priced at CA $1,149 found 5 days ago
Virgin Atlantic
Wed, Oct 7 - Fri, Oct 9
SEA
Seattle
LHR
London
CA $1,151 Roundtrip, found 5 days ago
CA $1,151
Roundtrip
found 5 days ago
Select Virgin Atlantic flight, departing Wed, Oct 7 from Seattle to London, returning Fri, Oct 9, priced at CA $1,151 found 5 days ago
Air France
Tue, Mar 2 - Wed, Mar 3
SEA
Seattle
LHR
London
CA $1,152 Roundtrip, found 3 days ago
CA $1,152
Roundtrip
found 3 days ago
Select Air France flight, departing Tue, Mar 2 from Seattle to London, returning Wed, Mar 3, priced at CA $1,152 found 3 days ago
Aer Lingus
Wed, Jul 29 - Thu, Aug 27
SEA
Seattle
LHR
London
CA $1,219 Roundtrip, found 15 hours ago
CA $1,219
Roundtrip
found 15 hours ago
Select Aer Lingus flight, departing Wed, Jul 29 from Seattle to London, returning Thu, Aug 27, priced at CA $1,219 found 15 hours ago
Finnair
Tue, Aug 25 - Fri, Sep 4
SEA
Seattle
LHR
London
CA $1,231 Roundtrip, found 17 hours ago
CA $1,231
Roundtrip
found 17 hours ago
Select Finnair flight, departing Tue, Aug 25 from Seattle to London, returning Fri, Sep 4, priced at CA $1,231 found 17 hours ago
KLM
Tue, Jul 21 - Wed, Aug 19
SEA
Seattle
LHR
London
CA $1,232 Roundtrip, found 4 days ago
CA $1,232
Roundtrip
found 4 days ago
Select KLM flight, departing Tue, Jul 21 from Seattle to London, returning Wed, Aug 19, priced at CA $1,232 found 4 days ago
United
Tue, Jul 21 - Wed, Aug 19
SEA
Seattle
LHR
London
CA $1,233 Roundtrip, found 4 days ago
CA $1,233
Roundtrip
found 4 days ago
Select United flight, departing Tue, Jul 21 from Seattle to London, returning Wed, Aug 19, priced at CA $1,233 found 4 days ago
American Airlines
Wed, Aug 19 - Fri, Aug 28
SEA
Seattle
LHR
London
CA $1,233 Roundtrip, found 1 day ago
CA $1,233
Roundtrip
found 1 day ago
Select American Airlines flight, departing Wed, Aug 19 from Seattle to London, returning Fri, Aug 28, priced at CA $1,233 found 1 day ago

Alternative airports near London

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Gatwick LGW. Average driving time to city centre is 52 minutes. Flights from CA $1,497
LGW
Gatwick
Average driving time to city centre52 min
Flights from CA $1,497
Select flight to London City LCY. Closest option available. Average driving time to city centre is 21 minutes. Flights from CA $3,297
LCY
London City
Closest
Average driving time to city centre21 min
Flights from CA $3,297

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

April is typically the cheapest month to fly

From CA $822 - CA $1,543 per traveller.

Frequently asked questions

How much does a flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) cost?
One-way flights typically cost between $639 and $4,369 and return flights often range between $1,082 and $7,158. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when Anaa (AAA) to Toronto, ON (YYZ-Pearson Intl.) ticket fares go up or down.
What is the cheapest month to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
October is typically the cheapest month to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow), with average round-trip fares of approximately 838 CAD. This is about 20% lower than the average price throughout the year. October often sees lower prices as the peak summer travel season has ended, and the holiday rush hasn't yet begun, leading to reduced demand. Other cheap months to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) include September and November.
Which airlines fly direct from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
Enter SEA to LHR and your travel dates, then apply the 'Nonstop' filter to see only direct flights.
How do I find cheap flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
To find a cheap flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best airline to fly with from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
The best airline to fly with from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) will differ from traveler to traveler. If you like to fly early, VS offers early morning flights. If price is the most important factor, VS typically offers the lowest fares. AS offers the most daily flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow), which is great if flexibility is what you value most. The best carrier for this journey could also be the one you have a loyalty membership with, as flying with that airline or another airline within the same alliance could help you collect points or enjoy lounge access.
What is the best time to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
Based on booking data from the past year, the cheapest months to fly from Seattle - Tacoma Intl. (SEA) to London Heathrow (LHR) are typically October and November, with average round-trip flight prices around 838 CAD. However, the most popular months for this route are April and December, which means you'll find plenty of flight options during those times. While there isn't a single month that is both the cheapest and most popular, if you prioritize savings, aim for October or November. If having a wide selection of flights is more important, consider April or December.
How many flights per day from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
There are approximately 4 nonstop flights per day from Seattle - Tacoma Intl. (SEA) to London Heathrow (LHR). For even more choice, look at flights that include layovers, as there are around 168 connecting flights per day. Some common connection points include O'Hare Intl. (ORD), John F. Kennedy Intl. (JFK), and Logan Intl. (BOS).
What is the earliest flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
The earliest flight from Seattle - Tacoma Intl. (SEA) to London Heathrow (LHR) typically departs at approximately 12:05 AM local time, operated by American Airlines. This is a seasonal service active in February. An early departure like this can help maximize your time at your destination. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What day of the week has the most flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
You'll typically find the most flights from Seattle - Tacoma Intl. (SEA) to London Heathrow (LHR) on a Tuesday, with around 122 flights available. This gives you plenty of options for your travel plans. Major airlines on this route include Delta Air Lines, American Airlines, and Alaska Airlines. Flight schedules are consistent throughout the week, so you'll have a good selection of flights no matter which day you choose.
What are the most popular departure times for flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
The most popular departure times for flights from Seattle - Tacoma Intl. (SEA) to Heathrow (LHR) are in the early morning, from 6am to 9am. About 23% of passengers prefer this time window. Many major carriers, including United Airlines, Delta Air Lines and Virgin Atlantic, offer flights during this window. This timing works well because it allows you to arrive at your destination with plenty of time to settle in or start your day.
How long does it take to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
Flying nonstop from SEA to LHR takes around 9 hours 30 minutes, with the route covering approximately 4,787 miles. Flights with a layover typically take 5 hours longer than direct options. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
Select the "Business class" and "First class" filters when looking for SEA to LHR flights on Expedia. This is the easiest way to compare prices, routes and flight times for your trip.
How much is a business class flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
A direct, round-trip business class ticket from Seattle - Tacoma Intl. (SEA) to Heathrow (LHR) typically costs between 19,668 CAD - 28,943 CAD. You may also be able to find a cheaper business class journey between Seattle - Tacoma Intl. Prices often fluctuate based on seasonality and how early you book. You may also be able to find a cheaper business class journey between Anaa (AAA) (AAA) to Toronto, ON (YYZ-Pearson Intl.) (YYZ) if you opt for a connecting flight.
How do I earn miles on a Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) flight with Expedia?
It's easy to earn miles on a Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia. *Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for London from Seattle - Tacoma Intl. (SEA)?
From Seattle - Tacoma Intl. (SEA), you can fly into London Intl. (YXU), London City (LCY), Gatwick (LGW) and Heathrow (LHR) in London. Some flights may connect through major hubs like Vancouver Intl. (YVR), O'Hare Intl. (ORD), Liberty Intl. (EWR) before reaching London. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) at the last minute?
Typically, booking a last minute flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) flight and hotel package?
Securing a Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays 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, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
If you booked your Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more 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
CA $908
Distance
7657 km
Average flight time
17 hours 35 mins

Book with confidence

Seattle to London Flights

The easy way to book your flights from Seattle to London 

With Expedia, it’s simple to find and book flights to London from Seattle whether you’re traveling for business or pleasure. Enter your travel dates, hit search, and choose your flight from 20 airlines that cover this route. There are nonstop flights to Heathrow, too.  

Choose your preferred carrier and cabin class with the advanced search tool and select your ideal departure time. Then, if you want, you can see just nonstop or refundable flights. And if you’re traveling last minute, just enter the date to check out flights from Seattle to London today, tomorrow, or this week.  

 

Save dollars with cheap flights from Seattle - Tacoma Intl., SEA to Heathrow, LHR 

Sort your search results by price to find great deals on your flight from Seattle to London—you get all your cheapest options first. Grab yourself a bargain now—the lowest price on flights to London from Seattle currently is just CA $909 rising to CA $1,233.  

Here are more money-saving tips: 

  • Fly in October when flight prices are normally at their lowest 
  • Book about a month to 6 weeks before you travel for the best prices to London  
  • Avoid peak season and weekends when flights can cost more
  • Early morning and late-night flights are sometimes cheaper, so try varying your travel times 
  • One surefire way to save money on your flight is to book your flight and hotel together with Expedia. Sometimes, the savings are so large that the flight is basically free! 

 

Reasons to choose Expedia for your flight to London from Seattle 

Whatever your destination, budget, or reason to travel, in just one quick search, you can choose from loads of flights, airlines, and cabin classes. The filters make it quick and easy to find your ideal flights, and if you choose one of the flexible options, you won’t be charged to change your flight. So book your flight to London with Expedia today.

Seattle to London Flights

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