HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
London

$412+ Cheap flights from Seattle (SEA) to London (LON)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/7. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — LON
apr. 19 — apr. 261
sø. 4/19
sø. 4/26
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Seattle to London with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.
Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London are usually found in October or January, booked 42 days in advance, depart on a Wednesday or Tuesday and return on a Wednesday

Cheap flight deals from Seattle to London

Cheapest flights from Seattle to London
Explore the most affordable flight options available from Seattle to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on mars 20, 2026.

This FlightHub deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
fr. 9/183:55 pm
SEA
-
LHR
2 stops33h 00m
Scandinavian Airlines
ma. 9/216:40 am
LHR
-
SEA
2 stops23h 25m
Scandinavian Airlines
Deal found 3/15$600
This Mytrip deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ma. 4/132:10 pm
SEA
-
STN
2 stops25h 25m
Multiple Airlines
ti. 4/285:45 pm
STN
-
SEA
2 stops31h 14m
Multiple Airlines
Deal found 3/16$605
This Gotogate deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
fr. 9/253:55 pm
SEA
-
LHR
1 stop33h 25m
Scandinavian Airlines
fr. 10/95:00 pm
LHR
-
SEA
1 stop28h 45m
Scandinavian Airlines
Deal found 3/16$608
This oojo deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 10/33:55 pm
SEA
-
LHR
1 stop16h 05m
Scandinavian Airlines
lø. 10/106:40 am
LHR
-
SEA
1 stop15h 05m
Scandinavian Airlines
Deal found 3/17$611
This Mytrip deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 4/147:00 pm
SEA
-
LGW
2 stops19h 20m
Multiple Airlines
ti. 4/216:25 am
LGW
-
SEA
2 stops22h 15m
Multiple Airlines
Deal found 3/17$615
This Kiwi.com deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sø. 9/133:55 pm
SEA
-
LHR
1 stop16h 05m
Scandinavian Airlines
fr. 9/256:40 am
LHR
-
SEA
1 stop15h 05m
Scandinavian Airlines
Deal found 3/15$616
This FlightHub deal was found by Cheapflights users on 3/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
fr. 9/253:55 pm
SEA
-
LHR
1 stop33h 25m
Scandinavian Airlines
lø. 10/106:40 am
LHR
-
SEA
1 stop15h 05m
Scandinavian Airlines
Deal found 3/16$617
This Mytrip deal was found by Cheapflights users on 3/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ma. 4/133:40 pm
SEA
-
LGW
2 stops20h 30m
Multiple Airlines
on. 4/229:20 am
LGW
-
SEA
2 stops19h 20m
Multiple Airlines
Deal found 3/15$620
This Mytrip deal was found by Cheapflights users on 3/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 4/283:40 pm
SEA
-
LGW
1 stop15h 00m
Icelandair
ti. 5/53:40 pm
LGW
-
SEA
1 stop34h 15m
Icelandair
Deal found 3/14$622
This KAYAK deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 8/253:55 pm
SEA
-
LHR
2 stops37h 00m
Scandinavian Airlines
fr. 8/2810:20 am
LHR
-
SEA
1 stop35h 25m
Scandinavian Airlines
Deal found 3/20$622
This Mytrip deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ma. 4/133:40 pm
SEA
-
LHR
3 stops22h 00m
Multiple Airlines
ma. 4/276:40 am
LHR
-
SEA
2 stops22h 00m
Multiple Airlines
Deal found 3/17$623
This Mytrip deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
fr. 4/247:00 pm
SEA
-
STN
2 stops17h 30m
Multiple Airlines
ma. 4/276:30 am
STN
-
SEA
3 stops35h 10m
Multiple Airlines
Deal found 3/17$625

Find flight deals from Seattle to London

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to London (LON). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated mars 20, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$605
(Mytrip)

One-way from

$412
(Kiwi.com)

Popular in

June

Cheapest in

October

Average price

$689

Good round-trip deal

$776 or less

Good one-way deal

$433 or less
Provider with most accurate pricing for Seattle/Tacoma Intl-London (LON) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-London (LON) flights.
Search Deals
From Seattle/Tacoma Intl to London (LON)
Search Deals
One-way flight from Seattle/Tacoma Intl to London (LON)
Search Deals
Highest demand for flights based on searches. 14% potential increase in price ($126 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($22 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals
Price to beat on a round-trip flight from Seattle/Tacoma Intl to London (LON).
Search Deals
Price to beat on a one-way flight from Seattle/Tacoma Intl to London (LON).
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to London that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated mars 20, 2026.
Use the filters below to find and compare flights from Seattle to London that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

lø. 9/5

2:30 pm-5:40 pm

2 stops19h 10m

London Heathrow

to. 10/1

7:30 pm-1:45 pm

1 stop26h 15m

$727

SeattleLondon

SEA - LTN

SEALTN

Seattle/Tacoma Intl

sø. 4/19

7:00 pm-9:45 pm

1 stop18h 45m

London Luton

fr. 4/24

6:05 am-5:55 pm

1 stop19h 50m

$800

SeattleLondon

SEA - LTN

SEALTN

Seattle/Tacoma Intl

on. 5/6

8:00 am-4:35 pm

3 stops24h 35m

London Luton

lø. 5/16

9:35 am-10:40 pm

3 stops21h 05m

$800

SeattleLondon

SEA - LTN

SEALTN

Seattle/Tacoma Intl

ti. 9/1

7:10 pm-3:30 pm

1 stop12h 20m

London Luton

ti. 9/8

9:40 am-5:10 pm

1 stop15h 30m

$830

SeattleLondon

SEA - LGW

SEALGW

Seattle/Tacoma Intl

ma. 5/4

7:00 am-8:20 am

2 stops17h 20m

London Gatwick

on. 6/3

9:20 am-8:53 pm

2 stops19h 33m

$840

SeattleLondon

SEA - SEN

SEASEN

Seattle/Tacoma Intl

on. 4/15

3:40 pm-9:25 pm

2 stops21h 45m

London Southend

sø. 4/19

7:25 am-10:53 pm

3 stops23h 28m

$855

SeattleLondon

SEA - LTN

SEALTN

Seattle/Tacoma Intl

lø. 5/2

7:10 pm-4:05 pm

1 stop12h 55m

London Luton

lø. 5/9

11:00 am-5:10 pm

1 stop14h 10m

$855

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

ti. 8/18

6:20 pm-12:10 pm

Nonstop9h 50m

London Heathrow

ti. 8/25

6:15 am-11:15 am

1 stop13h 00m

$857

SeattleLondon

SEA - LGW

SEALGW

Seattle/Tacoma Intl

to. 4/23

7:00 am-8:25 am

2 stops41h 25m

London Gatwick

sø. 5/10

6:35 pm-6:30 pm

2 stops31h 55m

$864

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

fr. 4/24

7:10 pm-10:10 pm

1 stop19h 00m

London Stansted

ma. 4/27

10:50 am-5:15 pm

1 stop38h 25m

$877

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/15

Showing 1-10 of 60 resultsSorted by cheapest first
1
2
3
...
6

Compare providers for flights from Seattle to London

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to London in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
OvagoPrice Accuracy2 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*2 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy1 starTrust Score*2 stars
Trip.comPrice Accuracy1 starTrust Score*3 stars
oojoPrice Accuracy3 starsTrust Score*3 stars
Thrive TravelPrice Accuracy3 starsTrust Score*2 stars
CheapTicketsDealPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-London flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-London flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-London flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-London flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-London flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Seattle to London

Have a flexible travel schedule? Discover the best time to fly to London from Seattle with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Seattle to London

How far ahead should I book a flight from Seattle to London?

Use this chart to determine the optimal time to book a round-trip flight from Seattle to London. Price data was last updated on March 13, 2026.

Booking 41 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to London. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Seattle to London?

Currently, February is the cheapest month in which you can book a flight from Seattle to London (average of $494). Flying from Seattle to London in June is currently the most expensive (average of $756). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from SEA to LON?

Find hourly flight availability from Seattle to London. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated mars 20, 2026.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Seattle to London as you normally would.

Weekly flight availability from Seattle to London

Explore weekly flight availability from Seattle to London. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated mars 20, 2026.

The most flights from SEA to LON are scheduled on a Thursday (15 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (11 on average).

What’s the top layover airport for flights from Seattle to London?

Share of 1-stop round-trip flights from Seattle to London chosen by Cheapflights users in the past 12 months, using the same layover each way.

Reykjavik (KEF) – chosen by Cheapflights users on 87% of 1-stop itineraries from Seattle to London on Cheapflights.

What’s the cheapest layover airport for flights from Seattle to London?

Average round-trip fare for 1-stop flights from Seattle to London, chosen by Cheapflights users in the past 12 months, with the same layover each way.

Reykjavik (KEF) is the most affordable 1-stop option, with an average round-trip price of $508.

What’s the fastest layover option from Seattle to London?

Shortest average travel time for 1-stop one-way flights from Seattle to London, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.

Flights via Dublin (DUB) have the shortest average one-way travel time for 1-stop routes: 12h 10m.

Which airport typically offers the quickest layover for flights from Seattle to London?

Average layover duration for 1-stop one-way flights from Seattle to London, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Reykjavik (KEF) offer the fastest connection on this route, with an average layover time of 1h 29m.

How often are flights from Seattle to London delayed?

About 16% of weekly flights between Seattle and London have experienced delays in the past year, with the average delay time being 121 minutes.

What is the most punctual flight time for Seattle to London flights?

Historically, flights departing in the early afternoon are less likely to be delayed, whereas flights leaving at night tend to experience delays more often.

What day of the week experiences the fewest flight delays on this route?

Tuesday tends to have the lowest number of delays on this route, whereas Wednesday has historically faced a higher average of delays compared to other days of the week.

Which airline has the best punctuality record on Seattle to London flights?

Over the last year, Virgin Atlantic have had the lowest number of delays on this route, with just 7% of flights being delayed.

The best insider tips for Seattle to London flights

AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to London trip
Our travel experts
Ramsey Qubein

Ramsey Qubein

Expert on LHR

An avid traveler and aviation expert who has visited 173 countries, all 50 states and seven continents, Ramsey Qubein flies nearly 400,000 miles a year. As a North Carolina-based freelance journalist for publications including Conde Nast Traveler, Forbes, USA Today and Bloomberg among others, he explores the latest trends in aviation, hospitality, cruises and business.

Read more
Brandon Schultz

Brandon Schultz

Expert on SEA

Brandon Schultz is an award-winning food and travel writer based in New York City. His work has appeared in Forbes, AAA, Thrillist, Travel + Leisure, and The Daily Meal, among many others, and he is the author of 6 books, including 3 cookbooks.

Read more

Reviews of airlines servicing London

Get insights into the airlines that provide service to London. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to London. Reviews last updated mars 20, 2026.
Peruse reviews from past customers who have flown with Delta,Virgin Atlantic, andAir France from Seattle to London to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
8,300 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Overall

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Delta
7.9
Good
8,300 reviews
Delta
7.9
Good
8,300 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Overall

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Virgin Atlantic
7.5
Good
682 reviews
Delta
7.9
Good
8,300 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Overall

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Air France
7.4
Good
1,547 reviews
Delta
7.9
Good
8,300 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Overall

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Icelandair
7.1
Good
622 reviews
Delta
7.9
Good
8,300 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Overall

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
British Airways
6.7
Okay
7,802 reviews
Delta
7.9
Good
8,300 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Overall

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.

Related info for your journey

Find useful and relevant information for your journey from Seattle to London. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from Seattle to London?

    If you book a flight to London from Seattle, you will be flying from Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 12 flights from Seattle/Tacoma Intl to London per day from 14 different airlines.

  • How long is the flight from Seattle to London?

    A quick flight from Seattle to London can take about 11h 45m. Scandinavian Airlines provides one of the quickest options available for as low as $834. The distance between Seattle and London is about 4794 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines flying from Seattle to London round-trip?

    Cheapflights users have booked flights from Seattle to London round-trip from $482. Other airlines that can offer you cheap pricing are Aer Lingus, from $500, and American Airlines, from $515. Users have found that Icelandair is 35% cheaper than the other options available to this destination.

  • What are the cheapest airlines to fly from Seattle to London one-way?

    One-way options have recently been found by users for as low as $162 on Icelandair. Other airlines that offer cheap prices include WestJet from $231 and Aer Lingus from $321 one-way.

  • What are the most popular routes from Seattle to London?

    When deciding which route to take from Seattle to London consider Seattle/Tacoma Intl - London Heathrow, Seattle/Tacoma Intl - London Gatwick or Seattle/Tacoma Intl - London Stansted as they are the most popular.

  • What are the most reliable airlines from Seattle to London?

    Consider American Airlines (85%), Alaska Airlines (85%) or Aer Lingus (85%) when booking your flight. These represent the most reliable airlines when flying from Seattle to London.

  • What are the cheapest flights from Seattle to London?

    Looking at all options, your cheapest flight can be booked for $311. While the most popular route (Seattle/Tacoma Intl - London Heathrow) can be booked for $562 on average, our data indicates $2,407 when flying from Seattle to London.

  • Can I find deals for flights from Seattle to London that include hotel bookings?

    Yes. In addition to deals on Seattle to London flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Seattle to London?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Seattle to London.

  • Can I find deals for business class flights from Seattle to London?

    Yes. Cheapflights offers flight deals from Seattle to London by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Seattle to London?

    Currently, February is the cheapest month in which you can book a flight from Seattle to London (average of $494). Flying from Seattle to London in June is currently the most expensive (average of $756). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near London?

Book flights to London if you plan to visit one of these locations
Ilford
Hounslow
Croydon
Gatwick
Southend-on-Sea
Harrow
Eastleigh
Dartford
Dover
Winchester
Orpington
Watford
Borehamwood
Aylesbury
Chipping Norton
Hayes
Kingston upon Thames
Eastbourne
Sutton
Slough

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Top 10 airlines flying from Seattle to London

Discover the top 10 airlines that operate flights from Seattle to London. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated mars 20, 2026.
AirlineCheapestAverageFlexibilityOn-time
IcelandairCheapest$482Average$621FlexibilityNo cancel feeOn-time76%
Aer LingusCheapest$500Average$726FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$515Average$785FlexibilityNo cancel feeOn-time71%
British AirwaysCheapest$527Average$725FlexibilityNo cancel feeOn-time70%
Scandinavian AirlinesCheapest$532Average$891FlexibilityNo cancel feeOn-time77%
Air FranceCheapest$532Average$761FlexibilityNo cancel feeOn-time77%
United AirlinesCheapest$547Average$842FlexibilityNo cancel feeOn-time69%
FinnairCheapest$556Average$694FlexibilityNo cancel feeOn-time76%
DeltaCheapest$559Average$845FlexibilityNo cancel feeOn-timeN/A
IberiaCheapest$565Average$748FlexibilityNo cancel feeOn-time77%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.