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$281+ 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 9/26. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — LON
Aug 28 — Sep 41
Fri 8/28
Fri 9/4
1 adult, Economy
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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London are usually found in January or November, booked 52 days in advance, depart on a Wednesday or Tuesday and return on a Monday

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 July 29, 2026.

This Mytrip deal was found by Cheapflights users on 7/27. 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.
Thu 9/105:50 am
SEA
-
LGW
3 stops29h 25m
Multiple Airlines
Thu 9/177:55 pm
LGW
-
SEA
2 stops24h 00m
Multiple Airlines
Deal found 7/27$629
This Mytrip deal was found by Cheapflights users on 7/28. 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.
Tue 11/102:35 pm
SEA
-
LGW
2 stops17h 45m
Multiple Airlines
Tue 11/177:30 pm
LGW
-
SEA
3 stops29h 30m
Multiple Airlines
Deal found 7/28$632
This Mytrip deal was found by Cheapflights users on 7/28. 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.
Tue 9/222:10 pm
SEA
-
LGW
2 stops21h 05m
Multiple Airlines
Tue 9/297:55 pm
LGW
-
SEA
3 stops30h 37m
Multiple Airlines
Deal found 7/28$633
This oojo deal was found by Cheapflights users on 7/28. 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.
Fri 9/183:55 pm
SEA
-
LHR
1 stop33h 25m
Scandinavian Airlines
Mon 9/216:40 am
LHR
-
SEA
2 stops39h 05m
Scandinavian Airlines
Deal found 7/28$633
This Mytrip deal was found by Cheapflights users on 7/27. 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.
Mon 8/177:00 pm
SEA
-
LGW
3 stops30h 10m
Multiple Airlines
Tue 8/2511:00 am
LGW
-
SEA
2 stops32h 45m
Multiple Airlines
Deal found 7/27$635
This Kiwi.com deal was found by Cheapflights users on 7/27. 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.
Sun 9/273:55 pm
SEA
-
STN
1 stop15h 45m
Multiple Airlines
Sat 10/38:35 am
STN
-
SEA
1 stop13h 10m
Multiple Airlines
Deal found 7/27$636
This Kiwi.com deal was found by Cheapflights users on 7/27. 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.
Fri 9/253:55 pm
SEA
-
STN
1 stop12h 45m
Multiple Airlines
Sun 10/117:05 am
STN
-
SEA
1 stop14h 40m
Multiple Airlines
Deal found 7/27$637
This Kiwi.com deal was found by Cheapflights users on 7/28. 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.
Fri 9/253:55 pm
SEA
-
STN
1 stop12h 45m
Multiple Airlines
Fri 10/26:20 am
STN
-
SEA
1 stop15h 25m
Multiple Airlines
Deal found 7/28$638
This Kiwi.com deal was found by Cheapflights users on 7/27. 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.
Sun 9/273:55 pm
SEA
-
STN
1 stop15h 45m
Multiple Airlines
Sun 10/47:05 am
STN
-
SEA
1 stop14h 40m
Multiple Airlines
Deal found 7/27$639
This Kiwi.com deal was found by Cheapflights users on 7/27. 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.
Fri 9/253:55 pm
SEA
-
STN
1 stop12h 45m
Multiple Airlines
Sat 10/38:35 am
STN
-
SEA
1 stop13h 10m
Multiple Airlines
Deal found 7/27$640
This Mytrip deal was found by Cheapflights users on 7/28. 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.
Thu 9/108:00 am
SEA
-
LHR
2 stops29h 20m
Multiple Airlines
Mon 9/219:05 pm
LHR
-
SEA
3 stops29h 27m
Multiple Airlines
Deal found 7/28$643
This Mytrip deal was found by Cheapflights users on 7/28. 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.
Mon 9/218:00 am
SEA
-
LGW
3 stops27h 15m
Multiple Airlines
Mon 10/55:00 pm
LGW
-
SEA
3 stops31h 59m
Multiple Airlines
Deal found 7/28$644

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 July 29, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$629
(Mytrip)

One-way from

$281
(KAYAK)

Popular in

June

Cheapest in

January

Average price

$1,045

Good round-trip deal

$825 or less

Good one-way deal

$374 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. 21% potential increase in price ($225 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($34 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 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 July 29, 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

Fri 9/18

7:15 am-1:35 pm

2 stops22h 20m

London Heathrow

Sun 9/20

6:40 am-1:45 pm

2 stops15h 05m

$669

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Sun 9/6

3:55 pm-5:00 pm

2 stops17h 05m

London Heathrow

Wed 9/16

7:05 am-11:20 pm

2 stops24h 15m

$779

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 12/15

2:35 pm-10:50 am

1 stop12h 15m

London Heathrow

Thu 1/7

12:15 pm-5:00 pm

1 stop12h 45m

$817

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Tue 10/6

7:15 pm-4:40 pm

1 stop37h 25m

London Stansted

Tue 10/13

5:35 pm-5:20 pm

1 stop31h 45m

$878

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Thu 10/1

7:15 pm-9:55 am

1 stop30h 40m

London Stansted

Fri 10/16

10:50 am-5:20 pm

1 stop38h 30m

$878

SeattleLondon

SEA - LTN

SEALTN

Seattle/Tacoma Intl

Mon 9/21

2:10 pm-7:05 pm

2 stops20h 55m

London Luton

Mon 10/5

7:55 am-9:04 pm

2 stops21h 09m

$887

SeattleLondon

SEA - LTN

SEALTN

Seattle/Tacoma Intl

Sat 9/19

3:40 pm-1:05 pm

1 stop13h 25m

London Luton

Wed 10/14

6:15 am-5:55 pm

1 stop19h 40m

$889

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Wed 9/23

6:50 pm-3:35 pm

1 stop12h 45m

London Stansted

Tue 9/29

11:00 am-4:59 pm

1 stop13h 59m

$899

SeattleLondon

SEA - LGW

SEALGW

Seattle/Tacoma Intl

Tue 9/8

9:59 am-4:00 pm

2 stops22h 01m

London Gatwick

Tue 9/15

10:35 am-5:48 pm

1 stop15h 13m

$913

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Tue 8/18

7:15 pm-4:40 pm

1 stop37h 25m

London Stansted

Wed 9/30

5:45 pm-5:20 pm

1 stop31h 35m

$918

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/25

Showing 1-10 of 60 resultsSorted by cheapest first
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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 July.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
OvagoPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy2 starsTrust Score*1 star
eDreamsPrice Accuracy2 starsTrust Score*3 stars
oojoPrice Accuracy3 starsTrust Score*2 stars
Kiwi.comPrice Accuracy3 starsTrust Score*3 stars
CheapTicketsDealPrice Accuracy1 starTrust 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

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

Currently, January is the cheapest month in which you can book a flight from Seattle to London (average of $638). Flying from Seattle to London in June is currently the most expensive (average of $1,212). 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 July 29, 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 July 29, 2026.

The most flights from SEA to LON are scheduled on a Tuesday (25 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (14 on average).

How much does it cost to fly round-trip from Seattle to London?

Airfare is typical for this route at the moment.
Seattle to London flights typically cost between $623 and $963 in September.
The cheapest round-trip price found within the last 5 days was $629 on Multiple Airlines (Sep 10-Sep 17).

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 77% 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 Reykjavik (KEF) have the shortest average one-way travel time for 1-stop routes: 12h 16m.

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 Frankfurt am Main (FRA) offer the fastest connection on this route, with an average layover time of 1h 13m.

How often are flights from Seattle to London delayed?

About 14% of weekly flights between Seattle and London have experienced delays in the past year, with the average delay time being 132 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 in the evening tend to experience delays more often.

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

Saturday 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 6% of flights being delayed.

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

Booking 64 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.

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 July 29, 2026.
Peruse reviews from past customers who have flown with Alaska Airlines,Delta, andVirgin Atlantic 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.
Alaska Airlines
7.9
Good
12,723 reviews

Entertainment

7.0

Crew

8.5

Food

7.0

Overall

7.9

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
6.0
Good

Anonymous,Jul 2026

SEA - LHR

Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle
Alaska Airlines
7.9
Good
12,723 reviews
Alaska Airlines
7.9
Good
12,723 reviews

Entertainment

7.0

Crew

8.5

Food

7.0

Overall

7.9

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
6.0
Good

Anonymous,Jul 2026

SEA - LHR

Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle
Delta
7.8
Good
8,483 reviews
Alaska Airlines
7.9
Good
12,723 reviews

Entertainment

7.0

Crew

8.5

Food

7.0

Overall

7.9

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
6.0
Good

Anonymous,Jul 2026

SEA - LHR

Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle
Virgin Atlantic
7.5
Good
694 reviews
Alaska Airlines
7.9
Good
12,723 reviews

Entertainment

7.0

Crew

8.5

Food

7.0

Overall

7.9

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
6.0
Good

Anonymous,Jul 2026

SEA - LHR

Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle
Icelandair
7.0
Good
715 reviews
Alaska Airlines
7.9
Good
12,723 reviews

Entertainment

7.0

Crew

8.5

Food

7.0

Overall

7.9

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
6.0
Good

Anonymous,Jul 2026

SEA - LHR

Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle
British Airways
6.7
Okay
8,129 reviews
Alaska Airlines
7.9
Good
12,723 reviews

Entertainment

7.0

Crew

8.5

Food

7.0

Overall

7.9

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
6.0
Good

Anonymous,Jul 2026

SEA - LHR

Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle

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 20 flights from Seattle/Tacoma Intl to London per day from 13 different airlines.

  • How long is the flight from Seattle to London?

    A quick flight from Seattle to London can take about 12h 15m. Scandinavian Airlines provides one of the quickest options available for as low as $817. The distance between Seattle and London is about 4783 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 $481. Other airlines that can offer you cheap pricing are Icelandair, from $484, and American Airlines, from $515. Users have found that Aer Lingus is 40% 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 $231 on WestJet. Other airlines that offer cheap prices include Icelandair from $256 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 KLM (82%), Air France (82%) or Delta (82%) 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 $302. While the most popular route (Seattle/Tacoma Intl - London Heathrow) can be booked for $559 on average, our data indicates $2,886 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, January is the cheapest month in which you can book a flight from Seattle to London (average of $638). Flying from Seattle to London in June is currently the most expensive (average of $1,212). 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
Dorking
Hounslow
Winchester
Croydon
Gatwick
Wembley
Harrow
Eastleigh
Southend-on-Sea
Watford
Dartford
Chipping Norton
Kingston upon Thames
Eastbourne
Slough
Stansted
Sutton
Luton
Harlow

Browse thousands of different options on Cheapflights for your next trip

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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 July 29, 2026.
AirlineCheapestAverageFlexibilityOn-time
Aer LingusCheapest$481Average$697FlexibilityNo cancel feeOn-timeN/A
IcelandairCheapest$484Average$694FlexibilityNo cancel feeOn-time76%
American AirlinesCheapest$515Average$839FlexibilityNo cancel feeOn-time71%
British AirwaysCheapest$517Average$798FlexibilityNo cancel feeOn-time70%
Virgin AtlanticCheapest$520Average$938FlexibilityNo cancel feeOn-time72%
DeltaCheapest$533Average$940FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$557Average$935FlexibilityNo cancel feeOn-time69%
FinnairCheapest$560Average$694FlexibilityNo cancel feeOn-time76%
Air FranceCheapest$563Average$781FlexibilityNo cancel feeOn-time77%
KLMCheapest$644Average$974FlexibilityNo cancel feeOn-time75%

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