How many flights depart from Seattle to London on average per week?

97 flights are operational weekly from Seattle to London as of January 2026. The most popular departure day for this route is Tue, with 22% of flights per week taking off on this day.

How often are flights from Seattle to London delayed?

Historically, on average around 16% of flights between Seattle and London have experienced a delay on any given week. The average delay length over the past 12 months has been 124 minutes.

How many flights depart from Seattle to London on average per day?

As of January 2026, 13 flights take off from Seattle and land in London each day. The most common flight departure time for this route is 18:00, with 56% of daily flights taking off in the evening.

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

Generally, flights departing in the early afternoon tend to experience fewer delays. Flights departing at night have, in the past, seen delays more frequently in comparison.

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

According to our data, Virgin Atlantic have had the fewest delays on this route over the last 12 months, with about 6% of their flights experiencing any sort of delay.

What is the cheapest airline that flies from Seattle/Tacoma Intl to London?

United Airlines, SWISS, and Lufthansa are the most popular carriers operating from Seattle/Tacoma Intl to London

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

Tuesday is statistically the day of the week that experiences the fewest delays on this flight route. Sunday has historically seen more delays on average compared to the rest of the week.

When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to London?

Prices for flights from Seattle/Tacoma Intl Airport to London were last updated today.

How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to London?

There are 2 operators available for flights from Seattle/Tacoma Intl Airport to London as of January 2026.

How old do you have to be to fly from Seattle/Tacoma Intl Airport to London?

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to London.

What documentation or ID do you need to fly to London?

The required travel and health documents for your London trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at London. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

£271 Cheap Flights from Seattle to London in 2026

Q: What is the typical price of a round-trip flight between Seattle and London?

Prices are currently low for flights on this route. Typical prices usually range from £438 to £575. The lowest price recently found on this route was £395.

1 adult

0 bags

Discover deals from 900+ travel sites with momondo.

Voted winner of Europe's Best Travel App 2023

Save money when you book flights with momondo

Big names, great deals

Search 100s of travel sites to compare prices.

Filter for what you want

Free Wi-Fi? Stopover? Instantly customise your results.

Trusted and free

We’re completely free to use - no hidden charges or fees.

Price Alerts

Not ready to book? to track prices.

Search flight deals

Find the cheapest flights from Seattle to London

Round-trip

One-way

Last minute

Direct

Cheap return flights

Enter your travel dates to find the best prices.

15:40 - 11:55

SEA

LHR

12h 15m

1 stop

13:05 - 17:55

LHR

SEA

12h 50m

1 stop

£395Icelandair

ons., 15 apr. - fre., 24 apr.

15:35 - 10:55

SEA

LGW

12h 20m

1 stop

15:40 - 20:40

LGW

SEA

13h 00m

1 stop

£395Icelandair

tir., 10 mar. - man., 13 apr.

15:35 - 21:20

SEA

LHR

22h 45m

2 stops

06:40 - 17:55

LHR

SEA

43h 15m

2 stops

£395Multiple Airlines

man., 16 mar. - søn., 29 mar.

15:40 - 19:35

SEA

STN

19h 55m

2 stops

06:30 - 20:40

STN

SEA

22h 10m

2 stops

£396Multiple Airlines

tor., 16 apr. - tir., 21 apr.

15:40 - 11:55

SEA

LHR

12h 15m

1 stop

21:25 - 20:40

LHR

SEA

31h 15m

1 stop

£396Icelandair

ons., 1 apr. - søn., 12 apr.

15:05 - 18:25

SEA

LCY

19h 20m

1 stop

17:50 - 11:35

LCY

SEA

25h 45m

1 stop

£475Virgin Atlantic

man., 23 feb. - man., 2 mar.

15:05 - 17:20

SEA

LCY

18h 15m

1 stop

17:05 - 11:35

LCY

SEA

26h 30m

1 stop

£477Virgin Atlantic

tir., 24 feb. - tir., 3 mar.

13:45 - 09:30

SEA

LCY

11h 45m

1 stop

10:00 - 16:35

LCY

SEA

14h 35m

1 stop

£485KLM

tir., 21 juli - ons., 16 sep.

12:32 - 17:05

SEA

LCY

20h 33m

2 stops

09:15 - 21:01

LCY

SEA

19h 46m

2 stops

£486SWISS

tir., 24 feb. - tir., 3 mar.

13:45 - 09:30

SEA

LCY

11h 45m

1 stop

09:20 - 16:30

LCY

SEA

15h 10m

1 stop

£487KLM

man., 6 apr. - tor., 7 maj

Lufthansa flights from Seattle to London

Our best Lufthansa deals on Seattle to London flight tickets

Lufthansa

26 Feb

SEA09:55Seattle/Tacoma Intl

16h 15m

2 stops

LHR10:10London Heathrow

8 Mar

LHR07:40London Heathrow

18h 36m

2 stops

SEA18:16Seattle/Tacoma Intl

£427

Lufthansa

25 Feb

SEA09:55Seattle/Tacoma Intl

16h 15m

2 stops

LHR10:10London Heathrow

4 Mar

LHR06:35London Heathrow

14h 45m

1 stop

SEA13:20Seattle/Tacoma Intl

£430

Lufthansa

25 Mar

SEA16:10Seattle/Tacoma Intl

23h 45m

1 stop

LHR22:55London Heathrow

1 Apr

LHR06:55London Heathrow

18h 04m

1 stop

SEA16:59Seattle/Tacoma Intl

£431

Icelandair flights from Seattle to London

Our best Icelandair deals on Seattle to London flight tickets

Icelandair

15 Apr

SEA15:40Seattle/Tacoma Intl

12h 15m

1 stop

LHR11:55London Heathrow

24 Apr

LHR13:05London Heathrow

12h 50m

1 stop

SEA17:55Seattle/Tacoma Intl

£395

Icelandair

10 Mar

SEA15:35Seattle/Tacoma Intl

12h 20m

1 stop

LGW10:55London Gatwick

13 Apr

LGW15:40London Gatwick

13h 00m

1 stop

SEA20:40Seattle/Tacoma Intl

£395

Icelandair

1 Apr

SEA15:40Seattle/Tacoma Intl

12h 15m

1 stop

LHR11:55London Heathrow

12 Apr

LHR21:25London Heathrow

31h 15m

1 stop

SEA20:40Seattle/Tacoma Intl

£396

Fly from

Fly to

Route

Depart

Return

Price

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

ons. 15/4

15:40-11:55

1 stop12h 15m

London Heathrow

fre. 24/4

13:05-17:55

1 stop12h 50m

£395

SeattleLondon

SEA - LGW

SEALGW

Seattle/Tacoma Intl

tir. 10/3

15:35-10:55

1 stop12h 20m

London Gatwick

man. 13/4

15:40-20:40

1 stop13h 00m

£395

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

man. 16/3

15:35-21:20

2 stops22h 45m

London Heathrow

søn. 29/3

06:40-17:55

2 stops43h 15m

£395

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

tor. 16/4

15:40-19:35

2 stops19h 55m

London Stansted

tir. 21/4

06:30-20:40

2 stops22h 10m

£396

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

ons. 1/4

15:40-11:55

1 stop12h 15m

London Heathrow

søn. 12/4

21:25-20:40

1 stop31h 15m

£396

SeattleLondon

SEA - LCY

SEALCY

Seattle/Tacoma Intl

man. 23/2

15:05-18:25

1 stop19h 20m

London City

man. 2/3

17:50-11:35

1 stop25h 45m

£475

SeattleLondon

SEA - LCY

SEALCY

Seattle/Tacoma Intl

tir. 24/2

15:05-17:20

1 stop18h 15m

London City

tir. 3/3

17:05-11:35

1 stop26h 30m

£477

SeattleLondon

SEA - LCY

SEALCY

Seattle/Tacoma Intl

tir. 21/7

13:45-09:30

1 stop11h 45m

London City

ons. 16/9

10:00-16:35

1 stop14h 35m

£485

SeattleLondon

SEA - LCY

SEALCY

Seattle/Tacoma Intl

tir. 24/2

12:32-17:05

2 stops20h 33m

London City

tir. 3/3

09:15-21:01

2 stops19h 46m

£486

SeattleLondon

SEA - LCY

SEALCY

Seattle/Tacoma Intl

man. 6/4

13:45-09:30

1 stop11h 45m

London City

tor. 7/5

09:20-16:30

1 stop15h 10m

£487

Flights are sorted by cheapest return flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Seattle to London

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Delays

Other information

What is the typical price of a round-trip flight between Seattle and London?

What is the cheapest month to fly to London?

The cheapest month to fly to London from Seattle is in October. Flight prices, which tend to average around £471, are often lower during this time because this is during the off-season. The month of January is another great option to travel to London, with average flight prices from Seattle averaging around £473.

What is the cheapest day to depart on your flight to London?

Our data shows that Tuesday is the least expensive day to fly to London. Tickets to fly out on this day can be as low as £500. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from Seattle to London for around £639.

What is the cheapest time of day to depart on your flight to London?

The cheapest time of day to fly to London is at midday when flights can be purchased for as low as £508. Flights in the afternoon are often more expensive, with an average ticket price of £592.

What is the cheapest Seattle/Tacoma Intl to London flight route?

Fly from Seattle/Tacoma Intl to London Heathrow for the best Seattle/Tacoma Intl - London flight prices

How far in advance should I book a flight to London?

You are more likely to see cheaper flights to London from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to London for around £570 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from Seattle for as low as £492 on momondo.

What cabin class options are available on Seattle/Tacoma Intl to London flights?

There are 3 cabin classes available to choose from on Seattle/Tacoma Intl to London flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Seattle to London flights?

You could potentially save up to 12% on your flight if you consider stops on a Seattle to London flight.

How have Seattle to London flight prices changed over time?

As of January 2026, prices for Seattle to London flights are approximately 3% more expensive when compared to flights at the same time last year.

When to book flights from Seattle to London

Are you open to changing your travel dates? Check out the ideal times to fly from Seattle to London according to our flight data. Find out which month and days have the cheapest flights.

Estimated return price

Cheap Seattle to London (SEA to LON) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Seattle to London

Best price found	£338
Fastest flight time	9h 15m
Direct flights	Every day
Airports in London	6 airports

The best one-way flight to London from Seattle in the past 72 hours is £338. The best return flight deal from Seattle to London found on momondo in the last 72 hours is £507.

The fastest flight from Seattle to London takes 9h 15m

Direct flights go from Seattle to London every day.

There are 6 airports in London. From Seattle there are direct flights to London Heathrow (LHR).

Search flight deals

How far is Seattle/Tacoma Intl to London by plane?
London is 4781.3 mi away from Seattle/Tacoma Intl. Typically, this will take 9h 15m by plane in normal conditions.
When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to London?
Prices for flights from Seattle/Tacoma Intl Airport to London were last updated today.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to London?
There are 2 operators available for flights from Seattle/Tacoma Intl Airport to London as of January 2026.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to London?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to London.
What documentation or ID do you need to fly to London?
The required travel and health documents for your London trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at London. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular plane model from Seattle to London?
Based on momondo bookings for flights between Seattle and London, the leading plane model is Boeing 787-9 Dreamliner, making up 25.48% of the total bookings. Other popular models include Boeing 787-10 Dreamliner with 24.09%, Airbus A330-200 with 19.54%, and Airbus A330-900neo with 13.84%.
What is the most popular airline from Seattle to London?
Based on momondo bookings for flights between Seattle and London, the leading airline is Virgin Atlantic, making up 53% of the total bookings. Other popular airlines include Icelandair with 19%, British Airways with 16%, and KLM with 12%.

Best airlines flying from Seattle to London

Compare and see reviews for airlines that fly from Seattle to London with momondo

Airline	Rating	Free Cancellation	Price
British Airways	PriceFrom £345	Free Cancellation	Rating 6.7 7,704 reviews		Search British Airways flights
Virgin Atlantic	PriceFrom £360	Free Cancellation	Rating 7.5 678 reviews		Search Virgin Atlantic flights

Virgin Atlantic Flights From Seattle to London
Virgin Atlantic flies from Seattle to London around 10 times per week, with 678 momondo users rating the airline 7.5/10. The cheapest Virgin Atlantic deal from Seattle to London in the last 72 hours was £360 (round-trip), much lower than the average airfare cost of £573 for Virgin Atlantic flights on this route.
British Airways Flights From Seattle to London
Another popular option for Seattle to London flights is British Airways (6.7/10, 7,704 ratings). British Airways flies from Seattle to London around 8 times per week, with deals starting from £345 round-trip and rising to an average price of around £508.

Eastbourne

Milton Keynes

Luton

Gatwick

Maidstone

Slough

Southend-on-Sea

Canterbury

Ipswich

Ilford

Guildford

Chelmsford

Hayes

Dover

Folkestone

Worthing

Colchester

Bedford

Ramsgate

Chichester

Why use momondo?

Why should I use momondo to find a flight deal from Seattle to London?

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Seattle to London . Millions of users trust and use momondo every year so you are in good hands.

Can I find flights from Seattle to London with flexible booking policies on momondo?

Flights from Seattle to London with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

How can momondo help me find flights from Seattle to London?

Once all potential Seattle to London flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.

I’m not ready to book a flight from Seattle to London right now. Can momondo alert me if prices change?

Yes. momondo can track prices for Seattle to London flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.

An easier way to manage your London trip

We make it super easy to schedule, organise and travel with friends or family. Trips is free – and available to use no matter where you book.

Start using Trips

Find my bookings

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

1 adult

fre. 27/2

fre. 6/3

Email me momondo's favourite deals

By creating a price alert you accept our terms of use and privacy policy.

Find better results for your trip to the United Kingdom

Fly into one of these airports located in London

London City Airport

London Gatwick Airport

London Heathrow Airport

London Luton Airport

London Southend Airport

London Stansted Airport

Popular Cities in the United Kingdom

Flights to Manchesterfrom £32

Flights to Birminghamfrom £33

Flights to Edinburghfrom £31

Flights to Belfastfrom £28

Flights to Glasgowfrom £31

Flights to Bristolfrom £30

Flights to Newcastle upon Tynefrom £29

Flights to Liverpoolfrom £30

Flights to Aberdeenfrom £36

Flights to Leedsfrom £36

Flights to Invernessfrom £36

Flights to Newquayfrom £31

Cheap flights from Seattle to London from £271

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to London departing on 10/3. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

Big names, great deals

Big names, great deals

Filter for what you want

Filter for what you want

Trusted and free

Trusted and free

Price Alerts

Price Alerts

Find the cheapest flights from Seattle to London

Cheap return flights

Cheap one-way flights

Cheap last-minute flights

Cheap direct flights

Lufthansa flights from Seattle to London

Our best Lufthansa deals on Seattle to London flight tickets

Icelandair flights from Seattle to London

Our best Icelandair deals on Seattle to London flight tickets

momondo Fare Finder

Use the filters below to find and compare flights from Seattle to London that are best for you.

See travel insights to London from

How to get the cheapest flight ticket from Seattle to London

What is the typical price of a round-trip flight between Seattle and London?

What is the cheapest month to fly to London?

What is the cheapest day to depart on your flight to London?

Our data shows that Tuesday is the least expensive day to fly to London. Tickets to fly out on this day can be as low as £500. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from Seattle to London for around £639.

What is the cheapest time of day to depart on your flight to London?

The cheapest time of day to fly to London is at midday when flights can be purchased for as low as £508. Flights in the afternoon are often more expensive, with an average ticket price of £592.

What is the cheapest Seattle/Tacoma Intl to London flight route?

Fly from Seattle/Tacoma Intl to London Heathrow for the best Seattle/Tacoma Intl - London flight prices

How far in advance should I book a flight to London?

What cabin class options are available on Seattle/Tacoma Intl to London flights?

There are 3 cabin classes available to choose from on Seattle/Tacoma Intl to London flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Seattle to London flights?

You could potentially save up to 12% on your flight if you consider stops on a Seattle to London flight.

How have Seattle to London flight prices changed over time?

As of January 2026, prices for Seattle to London flights are approximately 3% more expensive when compared to flights at the same time last year.

What is the cheapest airline that flies from Seattle/Tacoma Intl to London?

United Airlines, SWISS, and Lufthansa are the most popular carriers operating from Seattle/Tacoma Intl to London

How often are flights from Seattle to London delayed?

Historically, on average around 16% of flights between Seattle and London have experienced a delay on any given week. The average delay length over the past 12 months has been 124 minutes.

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

Generally, flights departing in the early afternoon tend to experience fewer delays. Flights departing at night have, in the past, seen delays more frequently in comparison.

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

Tuesday is statistically the day of the week that experiences the fewest delays on this flight route. Sunday has historically seen more delays on average compared to the rest of the week.

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

According to our data, Virgin Atlantic have had the fewest delays on this route over the last 12 months, with about 6% of their flights experiencing any sort of delay.

How many flights depart from Seattle to London on average per day?

As of January 2026, 13 flights take off from Seattle and land in London each day. The most common flight departure time for this route is 18:00, with 56% of daily flights taking off in the evening.

How many flights depart from Seattle to London on average per week?

97 flights are operational weekly from Seattle to London as of January 2026. The most popular departure day for this route is Tue, with 22% of flights per week taking off on this day.

When to book flights from Seattle to London

Cheap Seattle to London (SEA to LON) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Seattle to London

Best price found

Fastest flight time

Direct flights

Airports in London

How far is Seattle/Tacoma Intl to London by plane?

When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to London?

How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to London?

How old do you have to be to fly from Seattle/Tacoma Intl Airport to London?

What documentation or ID do you need to fly to London?

What is the most popular plane model from Seattle to London?

What is the most popular airline from Seattle to London?

Best airlines flying from Seattle to London

Compare and see reviews for airlines that fly from Seattle to London with momondo

Virgin Atlantic Flights From Seattle to London

British Airways Flights From Seattle to London

Travelling to a place near London?

Why use momondo?

Why should I use momondo to find a flight deal from Seattle to London?

Can I find flights from Seattle to London with flexible booking policies on momondo?

How can momondo help me find flights from Seattle to London?

I’m not ready to book a flight from Seattle to London right now. Can momondo alert me if prices change?

An easier way to manage your London trip

We make it super easy to schedule, organise and travel with friends or family. Trips is free – and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.