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 119 minutes.

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.

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

United Airlines, Delta, and SWISS 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 January 2026, there are 95 flights per week flying from London to Seattle. The most common day of the week flights depart is Tue, with 18% of flights taking off on this day.

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

13 flights are operational daily from London to Seattle as of January 2026. The most popular departure time for this route is 14:00, with 80% of flights per day taking off in the afternoon.

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.

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.

€411 Cheap Flights from London to Seattle in 2026

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12:20 - 14:45

LHR

SEA

10h 25mdirect

16:55 - 10:30

SEA

LHR

9h 35mdirect

€456KLM

Mon, 16 Feb - Mon, 23 Feb

08:30 - 20:48

LHR

SEA

20h 18m2 stops

06:30 - 10:10

SEA

LHR

19h 40m1 stop

€457United Airlines

Thu, 4 Jun - Tue, 23 Jun

06:15 - 11:15

LHR

SEA

13h 00m1 stop

21:45 - 15:35

SEA

LHR

9h 50mdirect

€461Delta

Tue, 28 Apr - Wed, 13 May

09:25 - 22:37

LGW

SEA

21h 12m2 stops

10:48 - 08:20

SEA

LGW

37h 32m2 stops

€465SWISS

Tue, 21 Apr - Tue, 28 Apr

15:05 - 09:33

LHR

SEA

26h 28m1 stop

08:42 - 12:20

SEA

LHR

19h 38m2 stops

€465United Airlines

Sat, 25 Apr - Sat, 2 May

20:05 - 22:43

LHR

SEA

34h 38m2 stops

12:32 - 17:50

SEA

LHR

21h 18m2 stops

€467SWISS

Mon, 16 Feb - Mon, 23 Feb

12:20 - 14:49

LHR

SEA

10h 29mdirect

18:25 - 11:55

SEA

LHR

9h 30mdirect

€467Delta

Wed, 21 Jan - Thu, 29 Jan

11:55 - 17:00

LGW

SEA

13h 05m1 stop

14:35 - 10:55

SEA

LGW

12h 20m1 stop

€479Icelandair

Mon, 26 Jan - Thu, 29 Jan

11:55 - 17:00

LGW

SEA

13h 05m1 stop

14:35 - 10:55

SEA

LGW

12h 20m1 stop

€480Icelandair

Mon, 9 Feb - Wed, 18 Feb

11:30 - 00:44

LGW

SEA

21h 14m2 stops

18:55 - 08:55

SEA

LGW

30h 00m2 stops

€520British Airways

Wed, 22 Apr - Mon, 27 Apr

Icelandair flights from London to Seattle

Our best Icelandair deals on London to Seattle flight tickets

Icelandair

26 Jan

LGW11:55London Gatwick

13h 05m

1 stop

SEA17:00Seattle/Tacoma Intl

29 Jan

SEA14:35Seattle/Tacoma Intl

12h 20m

1 stop

LGW10:55London Gatwick

€479

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Icelandair

9 Feb

LGW11:55London Gatwick

13h 05m

1 stop

SEA17:00Seattle/Tacoma Intl

18 Feb

SEA14:35Seattle/Tacoma Intl

12h 20m

1 stop

LGW10:55London Gatwick

€480

Find similar

Icelandair

9 Feb

LGW11:55London Gatwick

13h 05m

1 stop

SEA17:00Seattle/Tacoma Intl

19 Feb

SEA14:35Seattle/Tacoma Intl

12h 20m

1 stop

LGW10:55London Gatwick

€493

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KLM flights from London to Seattle

Our best KLM deals on London to Seattle flight tickets

KLM

16 Feb

LHR12:20London Heathrow

10h 25m

SEA14:45Seattle/Tacoma Intl

23 Feb

SEA16:55Seattle/Tacoma Intl

9h 35m

LHR10:30London Heathrow

€456

Find similar

KLM

13 Mar

LHR06:30London Heathrow

13h 05m

1 stop

SEA12:35Seattle/Tacoma Intl

24 Mar

SEA17:40Seattle/Tacoma Intl

9h 50m

LHR10:30London Heathrow

€476

Find similar

KLM

12 Feb

LHR06:30London Heathrow

13h 10m

1 stop

SEA11:40Seattle/Tacoma Intl

16 Feb

SEA18:25Seattle/Tacoma Intl

9h 30m

LHR11:55London Heathrow

€477

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Fly from

Fly to

Route

Depart

Return

Price

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 16/2

12:20-14:45

Nonstop10h 25m

Seattle/Tacoma Intl

Mon 23/2

16:55-10:30

Nonstop9h 35m

€456

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Thu 4/6

08:30-20:48

2 stops20h 18m

Seattle/Tacoma Intl

Tue 23/6

06:30-10:10

1 stop19h 40m

€457

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 28/4

06:15-11:15

1 stop13h 00m

Seattle/Tacoma Intl

Wed 13/5

21:45-15:35

Nonstop9h 50m

€461

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Tue 21/4

09:25-22:37

2 stops21h 12m

Seattle/Tacoma Intl

Tue 28/4

10:48-08:20

2 stops37h 32m

€465

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Sat 25/4

15:05-09:33

1 stop26h 28m

Seattle/Tacoma Intl

Sat 2/5

08:42-12:20

2 stops19h 38m

€465

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 16/2

20:05-22:43

2 stops34h 38m

Seattle/Tacoma Intl

Mon 23/2

12:32-17:50

2 stops21h 18m

€466

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 21/1

12:20-14:49

Nonstop10h 29m

Seattle/Tacoma Intl

Thu 29/1

18:25-11:55

Nonstop9h 30m

€467

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Mon 26/1

11:55-17:00

1 stop13h 05m

Seattle/Tacoma Intl

Thu 29/1

14:35-10:55

1 stop12h 20m

€479

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Mon 9/2

11:55-17:00

1 stop13h 05m

Seattle/Tacoma Intl

Wed 18/2

14:35-10:55

1 stop12h 20m

€480

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Wed 22/4

11:30-00:44

2 stops21h 14m

Seattle/Tacoma Intl

Mon 27/4

18:55-08:55

2 stops30h 00m

€520

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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 February, then January is your next best option. Flight prices from London to Seattle during January average around €552.

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 €648 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 €595 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 January 2026, prices for London to Seattle flights are approximately 10% 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	9h 45m
Direct flights	Every day
Airports in Seattle	1 airport

The fastest flight from London to Seattle takes 9h 45m

Direct flights go from London to Seattle every day.

There is 1 airport in Seattle. From London there are direct flights to 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 9h 45m, 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 30.94% of all bookings. The subsequent popular models are Boeing 787-10 Dreamliner at 16.35%, Airbus A330-200 at 13.04%, and Boeing 777-300ER at 10.69%.

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 €411

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 3/3. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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

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How to get the cheapest flight ticket from London to Seattle

What is the cheapest month to fly to Seattle?

If you’re not able to fly to Seattle in February, then January is your next best option. Flight prices from London to Seattle during January average around €552.

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 January 2026, prices for London to Seattle flights are approximately 10% 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?

United Airlines, Delta, and SWISS 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 119 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?

13 flights are operational daily from London to Seattle as of January 2026. The most popular departure time for this route is 14:00, with 80% of flights per day taking off in the afternoon.

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

As of January 2026, there are 95 flights per week flying from London to Seattle. The most common day of the week flights depart is Tue, with 18% 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