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$340+ 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 1/21. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — LON
Jan 7 — Jan 141
Wed 1/7
Wed 1/14
1 adult, Economy
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3. Compare prices and book

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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London are usually found in November or October, booked 9 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 December 8, 2025.

This Cheapflightsfares deal was found by Cheapflights users on 12/8. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/3110:05 amSEA - LHR
2 stops16h 05mLufthansa
Mon 1/126:30 pmLHR - SEA
2 stops31h 44mLufthansa
Deal found 12/8$705
This United Airlines deal was found by Cheapflights users on 12/6. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/3110:05 amSEA - LHR
1 stop17h 45mUnited Airlines
Mon 1/124:40 pmLHR - SEA
2 stops33h 46mUnited Airlines
Deal found 12/6$726
This Mytrip deal was found by Cheapflights users on 12/7. 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 12/910:05 amSEA - STN
3 stops26h 25mMultiple Airlines
Sun 12/146:15 amSTN - SEA
2 stops24h 01mMultiple Airlines
Deal found 12/7$734
This Mytrip deal was found by Cheapflights users on 12/7. 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 12/910:05 amSEA - STN
3 stops26h 25mMultiple Airlines
Sat 12/138:25 pmSTN - SEA
2 stops33h 51mMultiple Airlines
Deal found 12/7$739
This United Airlines deal was found by Cheapflights users on 12/7. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/303:50 pmSEA - LHR
1 stop33h 50mUnited Airlines
Wed 1/76:00 pmLHR - SEA
1 stop36h 16mUnited Airlines
Deal found 12/7$753
This Cheapflightsfares deal was found by Cheapflights users on 12/7. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/73:40 pmSEA - LHR
1 stop12h 10mLufthansa
Wed 12/247:40 amLHR - SEA
1 stop13h 40mLufthansa
Deal found 12/7$757
This FlightHub deal was found by Cheapflights users on 12/7. 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.
Wed 12/316:50 pmSEA - LHR
Nonstop9h 30mBritish Airways
Mon 1/127:15 pmLHR - SEA
2 stops34h 32mBritish Airways
Deal found 12/7$759
This United Airlines deal was found by Cheapflights users on 12/7. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/238:00 pmSEA - LHR
1 stop31h 50mUnited Airlines
Fri 1/96:00 pmLHR - SEA
1 stop36h 16mUnited Airlines
Deal found 12/7$760
This Delta deal was found by Cheapflights users on 12/6. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/317:35 amSEA - LHR
1 stop16h 15mDelta
Sat 1/176:30 amLHR - SEA
1 stop13h 20mDelta
Deal found 12/6$761
This Air Canada deal was found by Cheapflights users on 12/7. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/238:00 pmSEA - LHR
1 stop31h 50mAir Canada
Fri 1/912:00 pmLHR - SEA
2 stops34h 31mAir Canada
Deal found 12/7$762
This Air Canada deal was found by Cheapflights users on 12/8. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/305:50 amSEA - LHR
2 stops17h 20mAir Canada
Wed 1/76:00 pmLHR - SEA
2 stops28h 31mAir Canada
Deal found 12/8$763
This Kiwi.com deal was found by Cheapflights users on 12/7. 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.
Mon 12/88:10 amSEA - LHR
1 stop14h 30mMultiple Airlines
Tue 12/169:00 amLHR - SEA
2 stops20h 00mMultiple Airlines
Deal found 12/7$764

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 December 8, 2025.

Most accurate provider

Mytrip
3 stars

Most trusted provider

Mytrip
3 stars

Round-trip from

$582
(Cheapflightsfares)

One-way from

$340
(Kiwi.com)

Popular in

June

Cheapest in

November

Average price

$967

Good round-trip deal

$659 or less

Good one-way deal

$414 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. 15% potential increase in price ($141 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($23 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
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 December 8, 2025.
Use the filters below to find and compare flights from Seattle to London that are best for you.

Fly from

Seattle

Fly to

London

Route

Depart

Return

Price

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Wed 1/21

8:10 am-6:10 pm

2 stops26h 00m

London Stansted

Wed 1/28

2:25 pm-12:10 pm

2 stops29h 45m

$585

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Fri 1/23

5:50 am-8:35 pm

3 stops30h 45m

London Stansted

Mon 1/26

9:20 pm-10:06 pm

3 stops32h 46m

$588

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Fri 1/16

3:10 pm-8:40 pm

3 stops21h 30m

London Stansted

Fri 1/23

8:30 pm-12:10 pm

3 stops23h 40m

$611

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Thu 1/8

4:45 pm-10:30 am

Nonstop9h 45m

London Heathrow

Wed 1/21

6:30 am-11:50 am

1 stop13h 20m

$613

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 3/3

6:25 pm-11:55 am

Nonstop9h 30m

London Heathrow

Fri 3/13

6:30 am-12:35 pm

1 stop13h 05m

$614

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Thu 2/26

4:55 pm-10:30 am

Nonstop9h 35m

London Heathrow

Thu 3/12

6:30 am-12:35 pm

1 stop13h 05m

$614

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 1/19

6:25 pm-11:55 am

Nonstop9h 30m

London Heathrow

Mon 1/26

6:30 am-11:50 am

1 stop13h 20m

$614

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 2/18

4:55 pm-10:30 am

Nonstop9h 35m

London Heathrow

Fri 2/27

6:30 am-11:40 am

1 stop13h 10m

$614

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 2/24

4:55 pm-10:30 am

Nonstop9h 35m

London Heathrow

Thu 3/12

6:30 am-12:35 pm

1 stop13h 05m

$614

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Thu 2/26

4:55 pm-10:30 am

Nonstop9h 35m

London Heathrow

Tue 3/10

6:30 am-12:35 pm

1 stop13h 05m

$614

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/8

Showing 1-10 of 60 results
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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 December.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*3 stars
OvagoPrice Accuracy2 starsTrust Score*2 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*2 stars
MytripPrice Accuracy3 starsTrust Score*3 stars
oojoPrice Accuracy3 starsTrust Score*3 stars
Trip.comPrice Accuracy2 starsTrust Score*3 stars
GotogatePrice 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 Mytrip to be most consistent on Cheapflights vs. Mytrip Users can find the same prices on Seattle-London flight deals on Cheapflights vs. Mytrip >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 Mytrip the most. Mytrip 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 December 5, 2025.

Booking 9 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, May 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 $789). 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 December 8, 2025.

One of the essential ways to save on airfare from Seattle to London is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight in the afternoon could potentially save you up to 26% on airfare.

What is the cheapest day to fly from Seattle to London?

Use this chart to determine the cheapest time to fly round-trip from Seattle to London. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Seattle to London flight should consider departing on Saturday at noon when fares are most often at their lowest. Saturday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

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 December 8, 2025.

The most flights from SEA to LON are scheduled on a Saturday (21 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (9 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 76% 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 $530.

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: 11h 35m.

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 15% of weekly flights between Seattle and London have experienced delays in the past year, with the average delay time being 126 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?

Tuesday tends to have the lowest number of delays on this route, whereas Sunday 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 5% 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
Airports
SEA

Plan to arrive at SEA at least two hours before your flight due to potentially long security lines.

Read more about SEAby Brandon Schultz
LHR

Take the Heathrow Express for the fastest route into central London from LHR, arriving at Paddington Station.

Read more about LHRby Ramsey Qubein
Our travel experts
Ramsey Qubein

Ramsey Qubein

Expert on LHR

Ramsey Qubein

Ramsey Qubein

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

Brandon Schultz

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 December 8, 2025.
Peruse reviews from past customers who have flown with Delta, Virgin Atlantic, and Icelandair 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
8,011 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.1

Crew

8.5

Food

7.3

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
8,011 reviews
Delta
7.9
Good
8,011 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.1

Crew

8.5

Food

7.3

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
675 reviews
Delta
7.9
Good
8,011 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.1

Crew

8.5

Food

7.3

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
7.0
Good
588 reviews
Delta
7.9
Good
8,011 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.1

Crew

8.5

Food

7.3

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.
Iberia
7.0
Good
3,043 reviews
Delta
7.9
Good
8,011 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.1

Crew

8.5

Food

7.3

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
7,571 reviews
Delta
7.9
Good
8,011 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.1

Crew

8.5

Food

7.3

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 14 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 9h 45m. Delta provides one of the quickest options available for as low as $613. 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 $465. Other airlines that can offer you cheap pricing are Icelandair, from $481, and Aer Lingus, from $500. Users have found that Scandinavian Airlines is 38% 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 $166 on Icelandair. Other airlines that offer cheap prices include WestJet from $222 and Aer Lingus from $362 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 City as they are the most popular.

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

    Consider KLM (87%), Delta (85%) or Virgin Atlantic (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 $336. While the most popular route (Seattle/Tacoma Intl - London Heathrow) can be booked for $477 on average, our data indicates $2,146 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, May 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 $789). 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
Southend-on-Sea
Harrow
Eastleigh
Dartford
Dover
Winchester
Croydon
Orpington
Watford
Hayes
Borehamwood
Aylesbury
Chipping Norton
Horley
Kingston upon Thames
Wembley
Folkestone
Eastbourne

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Alternative routes for Seattle to London

See prices for flight routes from nearby airports that may be better suited for you.
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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 December 8, 2025.
AirlineCheapestAverageFlexibilityOn-time
Scandinavian AirlinesCheapest$465Average$859FlexibilityNo cancel feeOn-time77%
IcelandairCheapest$482Average$648FlexibilityNo cancel feeOn-time76%
Aer LingusCheapest$500Average$695FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$517Average$826FlexibilityNo cancel feeOn-time71%
Air FranceCheapest$532Average$753FlexibilityNo cancel feeOn-time77%
British AirwaysCheapest$545Average$785FlexibilityNo cancel feeOn-time70%
United AirlinesCheapest$547Average$816FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$553Average$989FlexibilityNo cancel feeOn-time75%
FinnairCheapest$556Average$694FlexibilityNo cancel feeOn-time76%
DeltaCheapest$562Average$836FlexibilityNo cancel feeOn-timeN/A

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