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Cheap flights from London Heathrow Airport to Seattle from £366

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 Heathrow Airport to Seattle departing on 7/10. 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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Find the cheapest flights from London Heathrow Airport to Seattle

Cheap return flights

Scandinavian Airlines Logo
06:40 - 14:00LHR-SEA
15h 20m1 stop
Scandinavian Airlines Logo
16:20 - 15:35SEA-LHR
39h 15m2 stops
£442Scandinavian Airlines
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Fri, 17 Oct - Fri, 24 Oct
British Airways Logo
14:55 - 16:55LHR-SEA
10h 00mdirect
British Airways Logo
11:57 - 10:00SEA-LHR
14h 03m1 stop
£443British Airways
Find Deal
Tue, 24 Feb - Tue, 3 Mar
Multiple Airlines Logo
06:30 - 14:16LHR-SEA
15h 46m2 stops
Multiple Airlines Logo
10:00 - 09:35SEA-LHR
15h 35m2 stops
£444Multiple Airlines
Find Deal
Wed, 8 Oct - Tue, 14 Oct
Icelandair Logo
12:15 - 17:00LHR-SEA
12h 45m1 stop
Icelandair Logo
15:35 - 10:50SEA-LHR
12h 15m1 stop
£444Icelandair
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Wed, 5 Nov - Sun, 15 Mar
Finnair Logo
17:00 - 13:23LHR-SEA
28h 23m2 stops
Finnair Logo
13:56 - 12:00SEA-LHR
14h 04m1 stop
£445Finnair
Find Deal
Tue, 24 Feb - Tue, 3 Mar
Finnair Logo
17:00 - 10:23LHR-SEA
25h 23m2 stops
Finnair Logo
07:48 - 06:50SEA-LHR
15h 02m1 stop
£446Finnair
Find Deal
Tue, 24 Feb - Tue, 3 Mar
Virgin Atlantic Logo
13:25 - 15:30LHR-SEA
10h 05mdirect
Virgin Atlantic Logo
05:25 - 09:50SEA-LHR
20h 25m1 stop
£447Virgin Atlantic
Find Deal
Mon, 29 Sep - Mon, 13 Oct
Lufthansa Logo
10:50 - 16:59LHR-SEA
14h 09m1 stop
Lufthansa Logo
13:12 - 10:40SEA-LHR
13h 28m1 stop
£448Lufthansa
Find Deal
Fri, 26 Sep - Mon, 13 Oct
Virgin Atlantic Logo
17:25 - 19:50LHR-SEA
10h 25mdirect
Virgin Atlantic Logo
20:25 - 14:15SEA-LHR
9h 50mdirect
£452Virgin Atlantic
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Mon, 29 Sep - Mon, 13 Oct
Icelandair Logo
20:35 - 17:00LHR-SEA
28h 25m1 stop
Icelandair Logo
15:35 - 19:30SEA-LHR
20h 55m1 stop
£462Icelandair
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Thu, 6 Nov - Fri, 13 Mar

SWISS flights from London Heathrow Airport to Seattle

Our best SWISS deals on London Heathrow Airport to Seattle flight tickets
SWISS
28 Sept
LHR06:00London Heathrow
23h 15m
2 stops
SEA21:15Seattle/Tacoma Intl
15 Oct
SEA13:00Seattle/Tacoma Intl
20h 50m
2 stops
LHR17:50London Heathrow
£447
Find similar
SWISS
28 Sept
LHR06:00London Heathrow
23h 15m
2 stops
SEA21:15Seattle/Tacoma Intl
4 Dec
SEA15:25Seattle/Tacoma Intl
18h 25m
2 stops
LHR17:50London Heathrow
£471
Find similar

Virgin Atlantic flights from London Heathrow Airport to Seattle

Our best Virgin Atlantic deals on London Heathrow Airport to Seattle flight tickets
Virgin Atlantic
29 Sept
LHR13:25London Heathrow
10h 05m
SEA15:30Seattle/Tacoma Intl
13 Oct
SEA05:25Seattle/Tacoma Intl
20h 25m
1 stop
LHR09:50London Heathrow
£447
Find similar
Virgin Atlantic
22 Sept
LHR13:25London Heathrow
10h 05m
SEA15:30Seattle/Tacoma Intl
6 Oct
SEA17:35Seattle/Tacoma Intl
9h 45m
LHR11:20London Heathrow
£449
Find similar
Virgin Atlantic
29 Sept
LHR17:25London Heathrow
10h 25m
SEA19:50Seattle/Tacoma Intl
13 Oct
SEA20:25Seattle/Tacoma Intl
9h 50m
LHR14:15London Heathrow
£452
Find similar

momondo Fare Finder

 
Customise your flight search to find flights from London Heathrow Airport 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 17 September 2025.
Use the filters below to find and compare flights from London Heathrow Airport to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 17/10

06:40-14:00

1 stop15h 20m

Seattle/Tacoma Intl

Fri 24/10

16:20-15:35

2 stops39h 15m

£442

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 24/2

14:55-16:55

Nonstop10h 00m

Seattle/Tacoma Intl

Tue 3/3

11:57-10:00

1 stop14h 03m

£443

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 8/10

06:30-14:16

2 stops15h 46m

Seattle/Tacoma Intl

Tue 14/10

10:00-09:35

2 stops15h 35m

£444

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 5/11

12:15-17:00

1 stop12h 45m

Seattle/Tacoma Intl

Sun 15/3

15:35-10:50

1 stop12h 15m

£444

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 24/2

17:00-13:23

2 stops28h 23m

Seattle/Tacoma Intl

Tue 3/3

13:56-12:00

1 stop14h 04m

£445

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 24/2

17:00-10:23

2 stops25h 23m

Seattle/Tacoma Intl

Tue 3/3

07:48-06:50

1 stop15h 02m

£446

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 29/9

13:25-15:30

Nonstop10h 05m

Seattle/Tacoma Intl

Mon 13/10

05:25-09:50

1 stop20h 25m

£447

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 26/9

10:50-16:59

1 stop14h 09m

Seattle/Tacoma Intl

Mon 13/10

13:12-10:40

1 stop13h 28m

£448

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 29/9

17:25-19:50

Nonstop10h 25m

Seattle/Tacoma Intl

Mon 13/10

20:25-14:15

Nonstop9h 50m

£452

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Thu 6/11

20:35-17:00

1 stop28h 25m

Seattle/Tacoma Intl

Fri 13/3

15:35-19:30

1 stop20h 55m

£462

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 Heathrow Airport 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 Heathrow Airport and Seattle?

What is the cheapest month to fly to Seattle?

The cheapest month to fly to Seattle from London Heathrow Airport is in February. Flight prices, which tend to average around £474, are often lower during this time because this is during the off-season. The month of September is another great option to travel to Seattle, with average flight prices from London Heathrow Airport averaging around £502.

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 Heathrow Airport. The lowest ticket price found for a Wednesday departure recently was £581. 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 £686.

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 Heathrow Airport to Seattle in the evening for as low as £517. 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 afternoon are often more expensive, with an average ticket price of £616.

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

Fly from London Heathrow to Seattle/Tacoma Intl for the best London Heathrow - 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 Heathrow Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around £563 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 Heathrow Airport for as low as £509 on momondo.

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

There are 4 cabin classes available to choose from on London Heathrow 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 Heathrow Airport to Seattle flights?

No. A direct flight is the cheapest option for a flight between London Heathrow Airport to Seattle.

How have London Heathrow Airport to Seattle flight prices changed over time?

As of September 2025, prices for London Heathrow Airport to Seattle flights are approximately 18% cheaper when compared to flights at the same time last year.

When to book flights from London Heathrow Airport to Seattle

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

Cheap London Heathrow Airport to Seattle (LHR to SEA) flight deals and tips

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

Best price found

£575

Fastest flight time

9h 45m

Direct flights

Every day

Airports in Seattle

1 airport
The best one-way flight to Seattle from London Heathrow Airport in the past 72 hours is £575. The best return flight deal from London Heathrow Airport to Seattle found on momondo in the last 72 hours is £511.
The fastest flight from London Heathrow Airport to Seattle takes 9h 45m
Direct flights go from London Heathrow Airport to Seattle every day.
There is 1 airport near Seattle: Seattle/Tacoma Intl (SEA)
Search flight deals

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

    The distance between London Heathrow and Seattle/Tacoma Intl is about 4774.1 mi. A reasonable flight in good conditions will take 10h 00m.

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

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

  • How many operators does momondo search for flights from London Heathrow Airport to Seattle/Tacoma Intl Airport?

  • How old do you have to be to fly from London Heathrow Airport 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 Heathrow Airport to Seattle/Tacoma Intl Airport.

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

    The travel and health documents required for your trip to Seattle/Tacoma Intl Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Seattle/Tacoma Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

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

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

Best airlines flying from London Heathrow Airport to Seattle

Compare and see reviews for airlines that fly from London Heathrow Airport to Seattle with momondo
Airline
Rating
Free Cancellation
Price
IcelandairPriceFrom £349Free CancellationRating
7.0
544 reviews
Search Icelandair flights
Air FrancePriceFrom £379Free CancellationRating
7.4
1,468 reviews
Search Air France flights
LufthansaPriceFrom £389Free CancellationRating
6.8
7,407 reviews
Search Lufthansa flights
FinnairPriceFrom £390Free CancellationRating
7.6
1,324 reviews
Search Finnair flights
KLMPriceFrom £398Free CancellationRating
7.8
1,386 reviews
Search KLM flights
United AirlinesPriceFrom £399Free CancellationRating
7.4
8,924 reviews
Search United Airlines flights
Aer LingusPriceFrom £400Free CancellationRating
7.2
1,274 reviews
Search Aer Lingus flights
British AirwaysPriceFrom £421Free CancellationRating
6.7
7,363 reviews
Search British Airways flights
Virgin AtlanticPriceFrom £432Free CancellationRating
7.4
664 reviews
Search Virgin Atlantic flights
DeltaPriceFrom £438Free CancellationRating
7.9
7,957 reviews
Search Delta flights

  • Delta Flights From London Heathrow Airport to Seattle

    Delta operates around 12 flights from London Heathrow Airport to Seattle every week. The average price of these flights found in the last 72 hours has been £800, but momondo users have found Delta deals from London Heathrow Airport to Seattle from as low as £597 round-trip. Delta has been scored 7.9/10 in 7,957 reviews.

  • KLM Flights From London Heathrow Airport to Seattle

    KLM (7.8/10 from 1,386 reviews) operates around 12 flights from London Heathrow Airport to Seattle in any given week. The average KLM airfare for this route is around £762, with deals from around £543 rare but found on momondo. Referenced prices are for round-trip London Heathrow Airport 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
Tukwila
Renton
SeaTac

Why use momondo?

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

Finding the right flight to Seattle from London is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to Seattle quick and easy, saving you time and money.

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?

Once all potential London to Seattle flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.

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

Of course. momondo tracks the price of London to Seattle flights. All you need is a valid email address and we will do the rest; it is that quick and easy.

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