How often are flights from London to Seattle delayed?

Historically, on average around 13% of flights between London and Seattle have experienced a delay on any given week. The average delay length over the past 12 months has been 117 minutes.

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. Wednesday has historically seen more delays on average compared to the rest of the week.

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

12 flights are operational daily from London to Seattle as of November 2025. The most popular departure time for this route is 14:00, with 69% of flights per day taking off in the afternoon.

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

Finnair, United Airlines, and British Airways are the most popular carriers operating from London to Seattle/Tacoma Intl

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

As of November 2025, there are 89 flights per week flying from London to Seattle. The most common day of the week flights depart is Sat, with 29% of flights taking off on this day.

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

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

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

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

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

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

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

The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and stopovers. It is recommended that you verify with the airline you are booking with for travel from London to Seattle/Tacoma Intl Airport.

What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

The travel and health documents you'll need for your trip to Seattle/Tacoma Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's licence and a passport that is valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

€470 Cheap Flights from London to Seattle in 2025/26

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12:20 - 14:45LHR-SEA

10h 25mdirect

16:55 - 10:30SEA-LHR

9h 35mdirect

€553Delta

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Fri, 6 Feb - Sat, 28 Feb

06:30 - 11:40LHR-SEA

13h 10m1 stop

18:25 - 11:55SEA-LHR

9h 30mdirect

€554Delta

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Thu, 19 Feb - Sat, 28 Feb

06:30 - 11:40LHR-SEA

13h 10m1 stop

16:45 - 10:30SEA-LHR

9h 45mdirect

€555Multiple Airlines

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Thu, 19 Feb - Sun, 1 Mar

13:00 - 22:16LHR-SEA

17h 16m1 stop

15:00 - 15:50SEA-LHR

17h 50m1 stop

€557United Airlines

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Wed, 7 Jan - Fri, 13 Mar

14:30 - 22:46LHR-SEA

16h 16m1 stop

08:10 - 06:30SEA-LHR

14h 20m1 stop

€561United Airlines

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Fri, 26 Dec - Mon, 29 Dec

07:40 - 18:28LHR-SEA

18h 48m2 stops

14:10 - 11:15SEA-LHR

13h 05m1 stop

€562United Airlines

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Wed, 17 Dec - Wed, 7 Jan

09:25 - 11:30LHR-SEA

10h 05mdirect

13:57 - 11:40SEA-LHR

13h 43m1 stop

€568British Airways

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Sat, 21 Feb - Sun, 1 Mar

14:00 - 12:31LGW-SEA

30h 31m1 stop

23:10 - 10:00SEA-LGW

26h 50m1 stop

€596Multiple Airlines

Find Deal

Mon, 19 Jan - Sun, 25 Jan

11:55 - 17:00LGW-SEA

13h 05m1 stop

15:35 - 10:55SEA-LGW

12h 20m1 stop

€608Icelandair

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Sun, 1 Mar - Thu, 19 Mar

11:55 - 20:39LGW-SEA

16h 44m2 stops

14:35 - 10:55SEA-LGW

12h 20m1 stop

€646Icelandair

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Mon, 12 Jan - Mon, 26 Jan

Delta flights from London to Seattle

Our best Delta deals on London to Seattle flight tickets

Delta

6 Feb

LHR12:20London Heathrow

10h 25m

SEA14:45Seattle/Tacoma Intl

28 Feb

SEA16:55Seattle/Tacoma Intl

9h 35m

LHR10:30London Heathrow

€553

Find similar

Delta

19 Feb

LHR06:30London Heathrow

13h 10m

1 stop

SEA11:40Seattle/Tacoma Intl

28 Feb

SEA18:25Seattle/Tacoma Intl

9h 30m

LHR11:55London Heathrow

€554

Find similar

Delta

21 Feb

LHR15:05London Heathrow

10h 05m

SEA17:10Seattle/Tacoma Intl

1 Mar

SEA16:45Seattle/Tacoma Intl

9h 45m

LHR10:30London Heathrow

€568

Find similar

United Airlines flights from London to Seattle

Our best United Airlines deals on London to Seattle flight tickets

United Airlines

7 Jan

LHR13:00London Heathrow

17h 16m

1 stop

SEA22:16Seattle/Tacoma Intl

13 Mar

SEA15:00Seattle/Tacoma Intl

17h 50m

1 stop

LHR15:50London Heathrow

€557

Find similar

United Airlines

26 Dec

LHR14:30London Heathrow

16h 16m

1 stop

SEA22:46Seattle/Tacoma Intl

29 Dec

SEA08:10Seattle/Tacoma Intl

14h 20m

1 stop

LHR06:30London Heathrow

€561

Find similar

United Airlines

17 Dec

LHR07:40London Heathrow

18h 48m

2 stops

SEA18:28Seattle/Tacoma Intl

7 Jan

SEA05:00Seattle/Tacoma Intl

17h 20m

2 stops

LHR06:20London Heathrow

€562

Find similar

Fly from

Fly to

Route

Depart

Return

Price

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 6/2

12:20-14:45

Nonstop10h 25m

Seattle/Tacoma Intl

Sat 28/2

16:55-10:30

Nonstop9h 35m

€553

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Thu 19/2

06:30-11:40

1 stop13h 10m

Seattle/Tacoma Intl

Sat 28/2

18:25-11:55

Nonstop9h 30m

€554

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Thu 19/2

06:30-11:40

1 stop13h 10m

Seattle/Tacoma Intl

Sun 1/3

16:45-10:30

Nonstop9h 45m

€555

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 7/1

13:00-22:16

1 stop17h 16m

Seattle/Tacoma Intl

Fri 13/3

15:00-15:50

1 stop17h 50m

€557

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 26/12

14:30-22:46

1 stop16h 16m

Seattle/Tacoma Intl

Mon 29/12

08:10-06:30

1 stop14h 20m

€561

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 17/12

07:40-18:28

2 stops18h 48m

Seattle/Tacoma Intl

Wed 7/1

14:10-11:15

1 stop13h 05m

€562

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Sat 21/2

09:25-11:30

Nonstop10h 05m

Seattle/Tacoma Intl

Sun 1/3

13:57-11:40

1 stop13h 43m

€568

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Mon 19/1

14:00-12:31

1 stop30h 31m

Seattle/Tacoma Intl

Sun 25/1

23:10-10:00

1 stop26h 50m

€596

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Sun 1/3

11:55-17:00

1 stop13h 05m

Seattle/Tacoma Intl

Thu 19/3

15:35-10:55

1 stop12h 20m

€608

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Mon 12/1

11:55-20:39

2 stops16h 44m

Seattle/Tacoma Intl

Mon 26/1

14:35-10:55

1 stop12h 20m

€646

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How to get the cheapest flight ticket from London to Seattle

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 cheapest month to fly to Seattle?

If you’re not able to fly to Seattle in January, then February is your next best option. Flight prices from London to Seattle during February average around €574.

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

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

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

You are more likely to see cheaper flights to Seattle from London when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around €668 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from London for as low as €609 on momondo.

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

There are 2 cabin classes available to choose from on London to Seattle/Tacoma Intl 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 London to Seattle flights?

You could potentially save up to 71% on your flight if you consider stops on a London to Seattle flight.

How have London to Seattle flight prices changed over time?

As of November 2025, prices for London to Seattle flights are approximately 14% more expensive when compared to flights at the same time last year.

When to book flights from London to Seattle

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

Estimated return price

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

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

Fastest flight time	10h 28m
Direct flights	Every day
Airports in Seattle	1 airport

The fastest flight from London to Seattle takes 10h 28m

Direct flights go from London to Seattle every day.

There is 1 airport near Seattle: Seattle/Tacoma Intl (SEA)

Search flight deals

How far is London to Seattle/Tacoma Intl by plane?
Seattle/Tacoma Intl is 7694.7 km away from London. Flights usually cover this in 10h 05m, depending on flying conditions and air traffic around both airports.
When did momondo last update prices for flights from London to Seattle/Tacoma Intl Airport?
Prices for flights from London to Seattle/Tacoma Intl Airport were last updated today.
How old do you have to be to fly from London to Seattle/Tacoma Intl Airport?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and stopovers. It is recommended that you verify with the airline you are booking with for travel from London to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The travel and health documents you'll need for your trip to Seattle/Tacoma Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's licence and a passport that is valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from London to Seattle?
momondo data reveals that the most frequently booked plane model on the route from London to Seattle is Boeing 787-9 Dreamliner, representing 29.85% of all bookings. The subsequent popular models are Boeing 787-10 Dreamliner at 19.89%, Airbus A330-200 at 14.54%, and Airbus A330-900neo at 13.78%.

Aberdeen

Lynnwood

Why use momondo?

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

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from London to Seattle for you.

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

Flights from London to Seattle 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 London to Seattle?

momondo provides multiple filters to help you find the best flight to Seattle from London. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.

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

If you are not ready to book a flight from London to Seattle now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Seattle and let you know when they change.

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Cheap flights from London to Seattle from €470

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from London to Seattle departing on 27/2. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Delta flights from London to Seattle

Our best Delta deals on London to Seattle flight tickets

United Airlines flights from London to Seattle

Our best United Airlines deals on London to Seattle flight tickets

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

See travel insights to Seattle from

How to get the cheapest flight ticket from London to Seattle

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

What is the cheapest month to fly to Seattle?

If you’re not able to fly to Seattle in January, then February is your next best option. Flight prices from London to Seattle during February average around €574.

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

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

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

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

There are 2 cabin classes available to choose from on London to Seattle/Tacoma Intl 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 London to Seattle flights?

You could potentially save up to 71% on your flight if you consider stops on a London to Seattle flight.

How have London to Seattle flight prices changed over time?

As of November 2025, prices for London to Seattle flights are approximately 14% more expensive when compared to flights at the same time last year.

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

Finnair, United Airlines, and British Airways are the most popular carriers operating from London to Seattle/Tacoma Intl

How often are flights from London to Seattle delayed?

Historically, on average around 13% of flights between London and Seattle have experienced a delay on any given week. The average delay length over the past 12 months has been 117 minutes.

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

Generally, flights departing in the evening tend to experience fewer delays. Flights departing in the early afternoon 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. Wednesday has historically seen more delays on average compared to the rest of the week.

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

According to our data, Delta 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 London to Seattle on average per day?

12 flights are operational daily from London to Seattle as of November 2025. The most popular departure time for this route is 14:00, with 69% of flights per day taking off in the afternoon.

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

As of November 2025, there are 89 flights per week flying from London to Seattle. The most common day of the week flights depart is Sat, with 29% of flights taking off on this day.

When to book flights from London to Seattle

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

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

Fastest flight time

Direct flights

Airports in Seattle

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

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

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

What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

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

Travelling to a place near Seattle?

Why use momondo?

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

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

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

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

An easier way to manage your Seattle 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.

Find better results for your trip to the United States

Airports servicing Washington