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

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

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?

14 flights are operational daily from London to Seattle as of December 2025. 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 December 2025, there are 102 flights per week flying from London to Seattle. The most common day of the week flights depart is Fri, with 17% 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.

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 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.

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.

€453 Cheap Flights from London to Seattle in 2025/26

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06:30 - 12:10

LHR

SEA

13h 40m1 stop

15:40 - 10:10

SEA

LHR

34h 30m2 stops

€573Multiple Airlines

Mon, 2 Feb - Sun, 15 Feb

14:50 - 19:52

LHR

SEA

13h 02m1 stop

23:05 - 12:50

SEA

LHR

29h 45m2 stops

€578Multiple Airlines

Sat, 24 Jan - Sat, 31 Jan

14:55 - 16:55

LHR

SEA

10h 00mdirect

18:50 - 12:20

SEA

LHR

9h 30mdirect

€586Finnair

Mon, 2 Feb - Sun, 15 Feb

20:05 - 22:43

LHR

SEA

34h 38m2 stops

14:52 - 17:50

SEA

LHR

18h 58m2 stops

€595SWISS

Wed, 21 Jan - Wed, 23 Sep

14:55 - 16:55

LHR

SEA

10h 00mdirect

09:00 - 06:50

SEA

LHR

13h 50m1 stop

€596Finnair

Mon, 2 Feb - Sun, 15 Feb

15:00 - 22:06

LHR

SEA

15h 06m2 stops

15:40 - 10:10

SEA

LHR

34h 30m2 stops

€598Air Canada

Mon, 2 Feb - Sun, 15 Feb

07:30 - 18:26

LHR

SEA

18h 56m2 stops

07:00 - 06:20

SEA

LHR

15h 20m1 stop

€601United Airlines

Tue, 13 Jan - Wed, 28 Jan

07:30 - 18:26

LHR

SEA

18h 56m2 stops

05:15 - 06:30

SEA

LHR

17h 15m2 stops

€603United Airlines

Wed, 21 Jan - Wed, 16 Sep

06:30 - 12:20

LHR

SEA

13h 50m1 stop

08:42 - 10:10

SEA

LHR

17h 28m2 stops

€609United Airlines

Mon, 4 May - Mon, 18 May

18:40 - 21:12

LGW

SEA

34h 32m2 stops

12:35 - 17:50

SEA

LGW

21h 15m2 stops

€672SWISS

Sat, 17 Jan - Fri, 30 Jan

SWISS flights from London to Seattle

Our best SWISS deals on London to Seattle flight tickets

SWISS

21 Jan

LHR20:05London Heathrow

34h 38m

2 stops

SEA22:43Seattle/Tacoma Intl

23 Sept

SEA14:52Seattle/Tacoma Intl

18h 58m

2 stops

LHR17:50London Heathrow

€595

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SWISS

20 Jan

LHR20:05London Heathrow

33h 07m

2 stops

SEA21:12Seattle/Tacoma Intl

31 Jan

SEA12:35Seattle/Tacoma Intl

21h 15m

2 stops

LHR17:50London Heathrow

€629

Find similar

SWISS

2 Feb

LHR09:00London Heathrow

20h 12m

2 stops

SEA21:12Seattle/Tacoma Intl

15 Feb

SEA10:55Seattle/Tacoma Intl

42h 05m

2 stops

LHR13:00London Heathrow

€642

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British Airways flights from London to Seattle

Our best British Airways deals on London to Seattle flight tickets

British Airways

25 Jan

LHR15:00London Heathrow

16h 51m

1 stop

SEA23:51Seattle/Tacoma Intl

1 Feb

SEA18:50Seattle/Tacoma Intl

9h 30m

LHR12:20London Heathrow

€655

Find similar

British Airways

25 Jan

LHR14:10London Heathrow

16h 10m

1 stop

SEA22:20Seattle/Tacoma Intl

1 Feb

SEA18:50Seattle/Tacoma Intl

9h 30m

LHR12:20London Heathrow

€656

Find similar

British Airways

22 Jan

LHR14:55London Heathrow

10h 00m

SEA16:55Seattle/Tacoma Intl

26 Jan

SEA14:04Seattle/Tacoma Intl

13h 31m

1 stop

LHR11:35London Heathrow

€666

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Fly from

Fly to

Route

Depart

Return

Price

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 2/2

06:30-12:10

1 stop13h 40m

Seattle/Tacoma Intl

Sun 15/2

15:40-10:10

2 stops34h 30m

€573

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Sat 24/1

14:50-19:52

1 stop13h 02m

Seattle/Tacoma Intl

Sat 31/1

23:05-12:50

2 stops29h 45m

€578

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 2/2

14:55-16:55

Nonstop10h 00m

Seattle/Tacoma Intl

Sun 15/2

18:50-12:20

Nonstop9h 30m

€586

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 21/1

20:05-22:43

2 stops34h 38m

Seattle/Tacoma Intl

Wed 23/9

14:52-17:50

2 stops18h 58m

€595

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 2/2

14:55-16:55

Nonstop10h 00m

Seattle/Tacoma Intl

Sun 15/2

09:00-06:50

1 stop13h 50m

€596

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 2/2

15:00-22:06

2 stops15h 06m

Seattle/Tacoma Intl

Sun 15/2

15:40-10:10

2 stops34h 30m

€598

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 13/1

07:30-18:26

2 stops18h 56m

Seattle/Tacoma Intl

Wed 28/1

07:00-06:20

1 stop15h 20m

€601

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 21/1

07:30-18:26

2 stops18h 56m

Seattle/Tacoma Intl

Wed 16/9

05:15-06:30

2 stops17h 15m

€603

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 4/5

06:30-12:20

1 stop13h 50m

Seattle/Tacoma Intl

Mon 18/5

08:42-10:10

2 stops17h 28m

€609

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Sat 17/1

18:40-21:12

2 stops34h 32m

Seattle/Tacoma Intl

Fri 30/1

12:35-17:50

2 stops21h 15m

€672

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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 €560.

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 €650 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 €596 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 December 2025, prices for London to Seattle flights are approximately 15% 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 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 10h 28m, 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 32.57% of all bookings. The subsequent popular models are Boeing 787-10 Dreamliner at 18.69%, Airbus A330-200 at 15.29%, and Airbus A330-900neo at 10.85%.

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 €453

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 15/3. 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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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 January, then February is your next best option. Flight prices from London to Seattle during February average around €560.

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 December 2025, prices for London to Seattle flights are approximately 15% 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, KLM, and JetBlue 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?

14 flights are operational daily from London to Seattle as of December 2025. 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 December 2025, there are 102 flights per week flying from London to Seattle. The most common day of the week flights depart is Fri, with 17% 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