Cheap flights from London to Seattle from £400

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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Condor Logo
10:20 - 15:40
LGW
-
SEA
13h 20m1 stop
Condor Logo
17:40 - 14:35
SEA
-
LGW
12h 55m1 stop
£470Condor
Fri, 24 Apr - Tue, 28 Apr
United Airlines Logo
06:30 - 12:10
LHR
-
SEA
13h 40m1 stop
United Airlines Logo
10:58 - 07:55
SEA
-
LHR
12h 57m1 stop
£471United Airlines
Sat, 17 Jan - Sun, 1 Feb
Icelandair Logo
11:55 - 17:00
LGW
-
SEA
13h 05m1 stop
Icelandair Logo
14:35 - 10:55
SEA
-
LGW
12h 20m1 stop
£471Icelandair
Tue, 24 Feb - Tue, 3 Mar
Lufthansa Logo
06:55 - 16:59
LHR
-
SEA
18h 04m1 stop
Lufthansa Logo
15:40 - 13:20
SEA
-
LHR
13h 40m1 stop
£472Lufthansa
Fri, 10 Apr - Mon, 20 Apr
Virgin Atlantic Logo
06:20 - 11:25
LHR
-
SEA
13h 05m1 stop
Virgin Atlantic Logo
06:00 - 08:45
SEA
-
LHR
19h 45m1 stop
£474Virgin Atlantic
Thu, 5 Mar - Tue, 10 Mar
Icelandair Logo
11:55 - 17:00
LGW
-
SEA
13h 05m1 stop
Icelandair Logo
14:35 - 10:55
SEA
-
LGW
12h 20m1 stop
£475Icelandair
Mon, 26 Jan - Sun, 8 Feb
Lufthansa Logo
14:30 - 19:16
LHR
-
SEA
12h 46m1 stop
Lufthansa Logo
09:00 - 09:10
SEA
-
LHR
16h 10m2 stops
£475Lufthansa
Tue, 24 Feb - Tue, 3 Mar
British Airways Logo
14:55 - 16:55
LHR
-
SEA
10h 00mdirect
British Airways Logo
18:50 - 12:20
SEA
-
LHR
9h 30mdirect
£476British Airways
Fri, 13 Feb - Thu, 19 Feb
Virgin Atlantic Logo
12:20 - 14:45
LHR
-
SEA
10h 25mdirect
Virgin Atlantic Logo
13:30 - 10:00
SEA
-
LHR
13h 30m1 stop
£477Virgin Atlantic
Thu, 5 Mar - Tue, 10 Mar
British Airways Logo
13:30 - 21:46
LCY
-
SEA
40h 16m2 stops
British Airways Logo
15:21 - 08:35
SEA
-
LCY
33h 14m2 stops
£528British Airways
Thu, 9 Apr - Thu, 16 Apr

British Airways flights from London to Seattle

Our best British Airways deals on London to Seattle flight tickets
British Airways
11 Mar
LCY06:50London City
19h 30m
1 stop
SEA19:20Seattle/Tacoma Intl
18 Mar
SEA21:05Seattle/Tacoma Intl
14h 45m
2 stops
LCY18:50London City
British Airways
13 Feb
LHR14:55London Heathrow
10h 00m
SEA16:55Seattle/Tacoma Intl
19 Feb
SEA18:50Seattle/Tacoma Intl
9h 30m
LHR12:20London Heathrow
British Airways
13 Feb
LHR14:55London Heathrow
10h 00m
SEA16:55Seattle/Tacoma Intl
19 Feb
SEA18:50Seattle/Tacoma Intl
9h 30m
LHR12:20London Heathrow

Lufthansa flights from London to Seattle

Our best Lufthansa deals on London to Seattle flight tickets
Lufthansa
24 Feb
LHR14:30London Heathrow
12h 46m
1 stop
SEA19:16Seattle/Tacoma Intl
3 Mar
SEA09:00Seattle/Tacoma Intl
16h 10m
2 stops
LHR09:10London Heathrow
Lufthansa
6 Mar
LCY18:15London City
25h 55m
1 stop
SEA12:10Seattle/Tacoma Intl
10 Mar
SEA15:00Seattle/Tacoma Intl
19h 35m
1 stop
LCY17:35London City
Lufthansa
13 Jan
LHR19:15London Heathrow
26h 05m
1 stop
SEA13:20Seattle/Tacoma Intl
25 Jan
SEA07:00Seattle/Tacoma Intl
16h 55m
1 stop
LHR07:55London Heathrow

momondo Fare Finder

 
Customise your flight search to find flights from London to Seattle that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, momondo users made 279,928 searches. Data last updated 5 December 2025.
Use the filters below to find and compare flights from London to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Fri 24/4

10:20-15:40

1 stop13h 20m

Seattle/Tacoma Intl

Tue 28/4

17:40-14:35

1 stop12h 55m

£470

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Sat 17/1

06:30-12:10

1 stop13h 40m

Seattle/Tacoma Intl

Sun 1/2

10:58-07:55

1 stop12h 57m

£471

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Tue 24/2

11:55-17:00

1 stop13h 05m

Seattle/Tacoma Intl

Tue 3/3

14:35-10:55

1 stop12h 20m

£471

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 10/4

06:55-16:59

1 stop18h 04m

Seattle/Tacoma Intl

Mon 20/4

15:40-13:20

1 stop13h 40m

£472

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Thu 5/3

06:20-11:25

1 stop13h 05m

Seattle/Tacoma Intl

Tue 10/3

06:00-08:45

1 stop19h 45m

£474

LondonSeattle

LGW - SEA

LGWSEA

London Gatwick

Mon 26/1

11:55-17:00

1 stop13h 05m

Seattle/Tacoma Intl

Sun 8/2

14:35-10:55

1 stop12h 20m

£475

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 24/2

14:30-19:16

1 stop12h 46m

Seattle/Tacoma Intl

Tue 3/3

09:00-09:10

2 stops16h 10m

£475

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 13/2

14:55-16:55

Nonstop10h 00m

Seattle/Tacoma Intl

Thu 19/2

18:50-12:20

Nonstop9h 30m

£476

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Thu 5/3

12:20-14:45

Nonstop10h 25m

Seattle/Tacoma Intl

Tue 10/3

13:30-10:00

1 stop13h 30m

£477

LondonSeattle

LCY - SEA

LCYSEA

London City

Thu 9/4

13:30-21:46

2 stops40h 16m

Seattle/Tacoma Intl

Thu 16/4

15:21-08:35

2 stops33h 14m

£528

Flights are sorted by cheapest return flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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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 typical price of a round-trip flight between London and Seattle?

What is the cheapest month to fly to Seattle?

The cheapest month to fly to Seattle from London is in January. Flight prices, which tend to average around £499, are often lower during this time because this is during the off-season. The month of February is another great option to travel to Seattle, with average flight prices from London averaging around £499.

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

According to our data, Wednesday is the cheapest day to fly to Seattle from London. The lowest ticket price found for a Wednesday departure recently was £590. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. Be sure to avoid booking your departure on a Sunday as prices are generally higher than usual. According to our data, the average ticket price to Seattle on Sunday is £678.

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

According to our data, the cheapest time of day to fly to Seattle is in the evening. momondo users have found flights departing from London to Seattle in the evening for as low as £529. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the morning are often more expensive, with an average ticket price of £627.

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 £581 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 £530 on momondo.

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

There are 4 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 19% 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 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

Best price found

£445

Fastest flight time

9h 45m

Direct flights

Every day

Airports in Seattle

1 airport
The best one-way flight to Seattle from London in the past 72 hours is £445. The best return flight deal from London to Seattle found on momondo in the last 72 hours is £529.
The fastest flight from London to Seattle takes 9h 45m
Direct flights go from London to Seattle every day.
There is 1 airport near Seattle: Seattle/Tacoma Intl (SEA)
  • How far is London to Seattle/Tacoma Intl by plane?

    A flight from London to Seattle/Tacoma Intl will travel around 4781.3 mi. By plane, this route typically takes 9h 45m.

  • 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 are updated daily.

  • How many operators does momondo search 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?

    The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check 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 license 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?

  • What is the most popular airline from London to Seattle?

Best airlines flying from London to Seattle

Compare and see reviews for airlines that fly from London to Seattle with momondo
Airline
Rating
Free Cancellation
Price
IcelandairPriceFrom £327Free CancellationRating
7.0
584 reviews
Search Icelandair flights
Air FrancePriceFrom £387Free CancellationRating
7.4
1,500 reviews
Search Air France flights
FinnairPriceFrom £399Free CancellationRating
7.6
1,334 reviews
Search Finnair flights
LufthansaPriceFrom £402Free CancellationRating
6.8
7,612 reviews
Search Lufthansa flights
KLMPriceFrom £403Free CancellationRating
7.7
1,430 reviews
Search KLM flights
United AirlinesPriceFrom £408Free CancellationRating
7.4
9,066 reviews
Search United Airlines flights
British AirwaysPriceFrom £442Free CancellationRating
6.7
7,562 reviews
Search British Airways flights
Virgin AtlanticPriceFrom £444Free CancellationRating
7.5
675 reviews
Search Virgin Atlantic flights
DeltaPriceFrom £447Free CancellationRating
7.9
8,009 reviews
Search Delta flights
Aer LingusPriceFrom £459Free CancellationRating
7.2
1,384 reviews
Search Aer Lingus flights
  • Delta Flights From London to Seattle

    Delta flight deals from London to Seattle start from £447 round-trip. Over the 10 Delta flights for this route in a normal week, average airfare is usually £582 round-trip - but some users have found much cheaper deals with momondo.

  • KLM Flights From London to Seattle

    KLM (7.7/10 from 1,430 reviews) operates around 10 flights from London to Seattle in any given week. The average KLM airfare for this route is around £572, with deals from around £403 rare but found on momondo. Referenced prices are for round-trip London to Seattle flight searches in the last 72 hours.

Travelling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Fife
Renton
SeaTac
Tukwila

Why use momondo?

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

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from London to Seattle. momondo saves you time and could save you money on your trip.

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

Yes. momondo allows you to filter the results for London to Seattle flights to just show those with flexible booking policies.

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

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Seattle from London.

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

Yes. momondo can track prices for London to Seattle 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.

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1 adult
Sun 4/1
Sun 11/1

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