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

View AU$404 flight on Tue, 6 Apr 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 for one-way flights and round trip tickets for the period specified. Prices and availability are subject to change. Additional terms apply.

Scandinavian Airlines
Fri, 11 Sept - Fri, 25 Sept
SEA
Seattle
LHR
London
AU$1,014 Return, found 3 hours ago
AU$1,014
Return
found 3 hours ago
Select Scandinavian Airlines flight, departing Fri, 11 Sept from Seattle to London, returning Fri, 25 Sept, priced at AU$1,014 found 3 hours ago
Icelandair
Tue, 8 Sept - Thu, 24 Sept
SEA
Seattle
LHR
London
AU$1,081 Return, found 3 days ago
AU$1,081
Return
found 3 days ago
Select Icelandair flight, departing Tue, 8 Sept from Seattle to London, returning Thu, 24 Sept, priced at AU$1,081 found 3 days ago
United
Mon, 14 Sept - Fri, 25 Sept
SEA
Seattle
LHR
London
AU$1,238 Return, found 4 days ago
AU$1,238
Return
found 4 days ago
Select United flight, departing Mon, 14 Sept from Seattle to London, returning Fri, 25 Sept, priced at AU$1,238 found 4 days ago
Delta
Tue, 8 Sept - Thu, 24 Sept
SEA
Seattle
LHR
London
AU$1,289 Return, found 3 days ago
AU$1,289
Return
found 3 days ago
Select Delta flight, departing Tue, 8 Sept from Seattle to London, returning Thu, 24 Sept, priced at AU$1,289 found 3 days ago
Alaska Airlines
Mon, 14 Sept - Fri, 25 Sept
SEA
Seattle
LHR
London
AU$1,309 Return, found 4 days ago
AU$1,309
Return
found 4 days ago
Select Alaska Airlines flight, departing Mon, 14 Sept from Seattle to London, returning Fri, 25 Sept, priced at AU$1,309 found 4 days ago
Virgin Atlantic
Tue, 8 Sept - Thu, 24 Sept
SEA
Seattle
LHR
London
AU$1,331 Return, found 3 days ago
AU$1,331
Return
found 3 days ago
Select Virgin Atlantic flight, departing Tue, 8 Sept from Seattle to London, returning Thu, 24 Sept, priced at AU$1,331 found 3 days ago
Air Canada
Tue, 8 Sept - Thu, 24 Sept
SEA
Seattle
LHR
London
AU$1,337 Return, found 3 days ago
AU$1,337
Return
found 3 days ago
Select Air Canada flight, departing Tue, 8 Sept from Seattle to London, returning Thu, 24 Sept, priced at AU$1,337 found 3 days ago
British Airways
Mon, 14 Sept - Fri, 25 Sept
SEA
Seattle
LHR
London
AU$1,337 Return, found 4 days ago
AU$1,337
Return
found 4 days ago
Select British Airways flight, departing Mon, 14 Sept from Seattle to London, returning Fri, 25 Sept, priced at AU$1,337 found 4 days ago
KLM
Tue, 8 Sept - Thu, 24 Sept
SEA
Seattle
LHR
London
AU$1,369 Return, found 3 days ago
AU$1,369
Return
found 3 days ago
Select KLM flight, departing Tue, 8 Sept from Seattle to London, returning Thu, 24 Sept, priced at AU$1,369 found 3 days ago
Finnair
Fri, 11 Sept - Fri, 25 Sept
SEA
Seattle
LHR
London
AU$1,401 Return, found 3 hours ago
AU$1,401
Return
found 3 hours ago
Select Finnair flight, departing Fri, 11 Sept from Seattle to London, returning Fri, 25 Sept, priced at AU$1,401 found 3 hours ago

Frequently asked questions

How much does a flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow) cost?
You can find one-way and return flights from SEA to LHR with Expedia. 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 our cheapest fares first, and use the Price Tracking tool to receive alerts when SEA to LHR ticket fares go up or down.
What is the cheapest month to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
If you're looking for the cheapest time to fly from Seattle - Tacoma Intl. (SEA) to London Heathrow (LHR), October is typically your best bet! You can expect average return fares around AU$957. October often sees lower prices as the peak summer travel season has ended, and the holiday rush hasn't quite begun, leading to less demand. Other budget-friendly months to consider for this route include September and November.
Which airlines fly direct from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
There are 3 airlines offering direct flights from Seattle - Tacoma Intl. (SEA) to London (LHR-Heathrow). Here are the top carriers:
  • British Airways operates 14 direct flights from Seattle - Tacoma Intl. to London (LHR-Heathrow) every week.
  • Delta operates 7 direct flights from Seattle - Tacoma Intl. to London (LHR-Heathrow) every week.
  • Virgin Atlantic operates 7 direct flights from Seattle - Tacoma Intl. to London (LHR-Heathrow) every week.
What is the cheapest airline that flies from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
Delta is one of the cheapest airlines offering nonstop return flights from Seattle - Tacoma Intl. (SEA) to Heathrow (LHR), with tickets starting from around AU$1100 for flights that can be booked for departure within the next year. Alaska Airlines is one of the cheapest airlines offering connecting return flights from Seattle - Tacoma Intl. (SEA) to Heathrow (LHR), with tickets starting from around AU$1390. These prices are per adult for economy/coach class. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.
How do I find cheap flights from Seattle, WA (SEA) to London (LHR)?
To find a cheap flight from Seattle, WA (SEA) to London (LHR), 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, Alaska Airlines offers early morning flights. If price is the most important factor, Virgin Atlantic typically offers the lowest fares. Delta 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) to London (LHR)?
The best time to fly is usually mid-week (Tuesday or Wednesday) and during early morning hours as flights tend to be cheaper, less crowded, and generally more on-time. Avoid major holidays and peak vacation seasons for smoother travel. Combining off-peak days and hours often gives the best combination of cost, comfort, and convenience.
How many flights per day from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
You'll find approximately 4 nonstop flights per day from Seattle - Tacoma Intl. (SEA) to London Heathrow (LHR). For even more choices, look at flights that include layovers. There are around 161 connecting flights per day. Some common connection points include O'Hare Intl. (ORD), Logan Intl. (BOS), and John F. Kennedy Intl. (JFK).
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 Heathrow (LHR) typically departs around 12:05 AM local time, operated by American Airlines. This is a seasonal service, active only in February. An early departure like this can help you make the most of 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 Friday, with around 129 flights available. This gives you plenty of options for your travel plans. Major airlines on this route include Delta, American Airlines, and Alaska Airlines. Flight options are notably more on Fridays compared to other days of the week, offering you greater flexibility.
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 evening, from 6pm to 9pm. Many major carriers, including Virgin Atlantic, Aer Lingus and British Airways, offer flights during this window. Many travelers prefer this because it allows you to have a full day in Seattle before your flight and arrive in London in the morning, ready to start your day.
How long does it take to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
When flying from Seattle - Tacoma Intl. (SEA) to London Heathrow (LHR), you have a few options. A nonstop flight typically takes around 9 hours 48 minutes, covering a distance of approximately 7703 kilometres. If you opt for a one-stop flight, your travel time will be longer, usually around 14 hours 30 minutes. Flights with two or more stops will take even longer, with a typical duration of about 16 hours 48 minutes. Keep in mind that actual flight times can vary due to factors like wind patterns and air traffic, so it's always a good idea to allow for some extra time when planning your journey.
Can you fly business or first class from Seattle, WA (SEA-Seattle - Tacoma Intl.) to London (LHR-Heathrow)?
Yes, you can fly business class or first class between SEA and LHR. Airlines that offer business class service on this route include:
  • Aer Lingus
  • Lufthansa
  • Air France
  • British Airways
  • Alaska Airlines
  • Singapore Airlines
  • Air Canada
  • Korean Air
  • Skywest Air
  • Turkish Airlines
  • SAS
  • Virgin Atlantic
  • Delta
  • Icelandair
  • Horizon Air
  • United
  • Finnair
  • American Airlines
  • Edelweiss Air
  • Condor
First class cabins are available on British Airways, Alaska Airlines, United, and American Airlines.
How do I earn miles on a Seattle, WA (SEA) to London (LHR) flight with Expedia?
It's easy to earn miles on a Seattle, WA (SEA) to London (LHR) 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 (LHR) from Seattle, WA (SEA)?
If you're planning to travel to London from Seattle - Tacoma Intl. (SEA), you can fly directly into Heathrow (LHR). Some flights may connect through major hubs like Salt Lake City Intl. (SLC), Vancouver Intl. (YVR), or O'Hare Intl. (ORD) 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) to London (LHR) at the last minute?
Typically, booking a last minute flight from Seattle, WA (SEA) to London (LHR) 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) to London (LHR) flight and hotel package?
Securing a Seattle, WA (SEA) to London (LHR) 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) to London (LHR)?
If you booked your Seattle, WA (SEA) to London (LHR) 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
Air Canada, Air France, Alaska Airlines, American Airlines, Austrian Airlines, British Airways, Brussels Airlines, Delta, Finnair, Icelandair, KLM, Lufthansa, Scandinavian Airlines, Swiss International Air Lines, Turkish Airlines, United, Virgin Atlantic
Return price
AU$1,013
Distance
7657 km
Average flight time
17 hours 31 mins

Book with confidence

Your quick guide to flights from Seattle to London

Pick up great flights from Seattle to London

With Expedia, you have your pick of flights a day with 20 airlines covering flights from Seattle to London. Whether you’re on a business trip, a family holiday or a luxury break, just enter your travel dates, hit search then check out your choice of flights. Select from return, one way or multi-city flights, and use the advance search tool if you want a direct or refundable flight. You can narrow your search to show you just your preferred cabin class and airline, too. It’s all easy. You can book direct flights from Seattle to London that take around hours.

Find cheap flights from Seattle to London

From the great flight deals with prices currently ranging from AU$1,014 to AU$1,401, you can choose to see the cheapest flights first. Generally, you can book the cheapest flights from Seattle to London around 4 to 6 weeks in advance. If your travel dates are flexible, try to avoid weekends and peak seasons – when you are more likely to grab the lowest prices. Even last minute, there are some impressive deals. The cheapest time to fly to London is normally in September.

Reasons to book your flight from Seattle to London with Expedia

Expedia makes it easy to find, book, and travel, with everything you need all in one place. When you enter your travel details, find fantastic deals just for you on flight tickets from Seattle to London across all the main airline carriers, so you can save time, dollars, and hassle finding the perfect flight. If you think your plans could change, choose refundable flights so any changes won’t cost you more. Book your flight to London right now and, if you join Expedia Rewards, you earn points this time and every time you travel with Expedia.

Your quick guide to flights from Seattle to London

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