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

Thursday 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?

14 flights are operational daily from London to Seattle as of January 2026. The most popular departure time for this route is 14:00, with 81% of flights per day taking off in the afternoon.

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 4% of their flights experiencing any sort of delay.

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

As of January 2026, there are 102 flights per week flying from London to Seattle. The most common day of the week flights depart is Tue, with 21% 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 is the cheapest airline that flies from London to Seattle/Tacoma Intl?

SWISS, United Airlines, and Icelandair 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 11% 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 126 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.

€404 Cheap Flights from London to Seattle in 2026

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

Prices are currently low for flights on this route. Typical prices usually range from €459 to €653. The lowest price recently found on this route was €404.

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Find the cheapest flights from London to Seattle

Round-trip

One-way

Last minute

Direct

Cheap return flights

Enter your travel dates to find the best prices.

20:35 - 17:00

LHR

SEA

28h 25m

1 stop

14:35 - 10:50

SEA

LHR

12h 15m

1 stop

€404Icelandair

Tue, 24 Feb - Tue, 3 Mar

20:05 - 23:30

LHR

SEA

35h 25m

2 stops

20:00 - 10:10

SEA

LHR

30h 10m

2 stops

€412Multiple Airlines

Mon, 16 Feb - Mon, 2 Mar

15:40 - 20:40

LGW

SEA

13h 00m

1 stop

15:40 - 14:40

SEA

LGW

15h 00m

1 stop

€413Icelandair

Mon, 20 Apr - Fri, 24 Apr

20:05 - 23:30

LHR

SEA

35h 25m

2 stops

08:00 - 06:30

SEA

LHR

14h 30m

1 stop

€418Multiple Airlines

Mon, 16 Feb - Mon, 2 Mar

15:40 - 20:40

LGW

SEA

13h 00m

1 stop

15:40 - 14:40

SEA

LGW

15h 00m

1 stop

€420Icelandair

Sat, 25 Apr - Sat, 2 May

06:35 - 14:20

LHR

SEA

14h 45m

1 stop

12:25 - 09:10

SEA

LHR

13h 45m

1 stop

€423United Airlines

Fri, 13 Mar - Fri, 20 Mar

06:35 - 13:20

LHR

SEA

14h 45m

1 stop

23:35 - 21:20

SEA

LHR

13h 45m

1 stop

€423United Airlines

Wed, 11 Feb - Wed, 18 Feb

06:30 - 12:10

LHR

SEA

13h 40m

1 stop

12:25 - 09:10

SEA

LHR

13h 45m

1 stop

€424United Airlines

Thu, 5 Mar - Fri, 20 Mar

09:25 - 23:29

LGW

SEA

22h 04m

2 stops

09:55 - 17:50

SEA

LGW

23h 55m

2 stops

€434SWISS

Fri, 8 May - Tue, 19 May

09:15 - 22:37

LGW

SEA

21h 22m

2 stops

09:55 - 17:50

SEA

LGW

23h 55m

2 stops

€435SWISS

Wed, 29 Apr - Tue, 12 May

United Airlines flights from London to Seattle

Our best United Airlines deals on London to Seattle flight tickets

United Airlines

13 Mar

LHR06:35London Heathrow

14h 45m

1 stop

SEA14:20Seattle/Tacoma Intl

20 Mar

SEA12:25Seattle/Tacoma Intl

13h 45m

1 stop

LHR09:10London Heathrow

€423

United Airlines

11 Feb

LHR06:35London Heathrow

14h 45m

1 stop

SEA13:20Seattle/Tacoma Intl

18 Feb

SEA23:35Seattle/Tacoma Intl

13h 45m

1 stop

LHR21:20London Heathrow

€423

United Airlines

5 Mar

LHR06:30London Heathrow

13h 40m

1 stop

SEA12:10Seattle/Tacoma Intl

20 Mar

SEA12:25Seattle/Tacoma Intl

13h 45m

1 stop

LHR09:10London Heathrow

€424

Icelandair flights from London to Seattle

Our best Icelandair deals on London to Seattle flight tickets

Icelandair

24 Feb

LHR20:35London Heathrow

28h 25m

1 stop

SEA17:00Seattle/Tacoma Intl

3 Mar

SEA14:35Seattle/Tacoma Intl

12h 15m

1 stop

LHR10:50London Heathrow

€404

Icelandair

20 Apr

LGW15:40London Gatwick

13h 00m

1 stop

SEA20:40Seattle/Tacoma Intl

24 Apr

SEA15:40Seattle/Tacoma Intl

15h 00m

1 stop

LGW14:40London Gatwick

€413

Icelandair

25 Apr

LGW15:40London Gatwick

13h 00m

1 stop

SEA20:40Seattle/Tacoma Intl

2 May

SEA15:40Seattle/Tacoma Intl

15h 00m

1 stop

LGW14:40London Gatwick

€420

Fly from

Fly to

Route

Depart

Return

Price

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 24/2

20:35-17:00

1 stop28h 25m

Seattle/Tacoma Intl

Tue 3/3

14:35-10:50

1 stop12h 15m

€404

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 16/2

20:05-23:30

2 stops35h 25m

Seattle/Tacoma Intl

Mon 2/3

20:00-10:10

2 stops30h 10m

€412

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Mon 20/4

15:40-20:40

1 stop13h 00m

Seattle/Tacoma Intl

Fri 24/4

15:40-14:40

1 stop15h 00m

€413

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 16/2

20:05-23:30

2 stops35h 25m

Seattle/Tacoma Intl

Mon 2/3

08:00-06:30

1 stop14h 30m

€418

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Sat 25/4

15:40-20:40

1 stop13h 00m

Seattle/Tacoma Intl

Sat 2/5

15:40-14:40

1 stop15h 00m

€420

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 13/3

06:35-14:20

1 stop14h 45m

Seattle/Tacoma Intl

Fri 20/3

12:25-09:10

1 stop13h 45m

€423

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 11/2

06:35-13:20

1 stop14h 45m

Seattle/Tacoma Intl

Wed 18/2

23:35-21:20

1 stop13h 45m

€423

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Thu 5/3

06:30-12:10

1 stop13h 40m

Seattle/Tacoma Intl

Fri 20/3

12:25-09:10

1 stop13h 45m

€424

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Fri 8/5

09:25-23:29

2 stops22h 04m

Seattle/Tacoma Intl

Tue 19/5

09:55-17:50

2 stops23h 55m

€434

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Wed 29/4

09:15-22:37

2 stops21h 22m

Seattle/Tacoma Intl

Tue 12/5

09:55-17:50

2 stops23h 55m

€435

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 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 typical price of a round-trip flight between London and 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 €540.

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 €630 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 €589 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 76% 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 7% cheaper 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 27.39% of all bookings. The subsequent popular models are Boeing 787-10 Dreamliner at 17.87%, Boeing 777-300ER at 12.01%, and Airbus A330-900neo at 11.60%.

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 €404

This is the cheapest return flight price found by a momondo user in the last 72 hours by searching for a flight from London to Seattle departing on 24/2. 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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Our best Icelandair 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

What is the typical price of a round-trip flight between London and 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 €540.

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 76% 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 7% cheaper when compared to flights at the same time last year.

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

SWISS, United Airlines, and Icelandair 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 11% 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 126 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?

Thursday 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 4% 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 January 2026. The most popular departure time for this route is 14:00, with 81% 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 102 flights per week flying from London to Seattle. The most common day of the week flights depart is Tue, with 21% 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