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Cheap flights from London Heathrow Airport to Seattle from £257

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 20/5. 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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0 bags

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Find the cheapest flights from London Heathrow Airport to Seattle

Cheap return flights

KAYAK's recommended return flight deals from the most popular airlines that fly from London Heathrow Airport to Seattle.
United Airlines Logo
06:50 - 22:43LHR-SEA
23h 53m2 stops
United Airlines Logo
06:15 - 11:35SEA-LHR
21h 20m2 stops
£313United Airlines
Find Deal
Tue, 29 Apr - Tue, 13 May
United Airlines Logo
12:05 - 21:41LHR-SEA
17h 36m1 stop
United Airlines Logo
06:15 - 11:35SEA-LHR
21h 20m2 stops
£331United Airlines
Find Deal
Mon, 28 Apr - Tue, 13 May
Icelandair Logo
21:25 - 20:40LHR-SEA
31h 15m1 stop
Icelandair Logo
15:45 - 11:55SEA-LHR
12h 10m1 stop
£416Icelandair
Find Deal
Mon, 5 May - Wed, 14 May
Icelandair Logo
13:05 - 20:40LHR-SEA
15h 35m1 stop
Icelandair Logo
19:00 - 20:20SEA-LHR
17h 20m1 stop
£433Icelandair
Find Deal
Tue, 6 May - Tue, 13 May
KLM Logo
09:55 - 15:57LHR-SEA
14h 02m1 stop
KLM Logo
17:35 - 11:20SEA-LHR
9h 45mdirect
£470KLM
Find Deal
Mon, 5 May - Wed, 14 May
Virgin Atlantic Logo
11:45 - 11:40LHR-SEA
31h 55m1 stop
Virgin Atlantic Logo
20:20 - 14:15SEA-LHR
9h 55mdirect
£476Virgin Atlantic
Find Deal
Tue, 6 May - Mon, 12 May
Virgin Atlantic Logo
13:25 - 15:45LHR-SEA
10h 20mdirect
Virgin Atlantic Logo
17:35 - 11:20SEA-LHR
9h 45mdirect
£477Virgin Atlantic
Find Deal
Mon, 28 Apr - Tue, 13 May
British Airways Logo
10:30 - 16:59LHR-SEA
14h 29m1 stop
British Airways Logo
20:20 - 13:40SEA-LHR
9h 20mdirect
£480British Airways
Find Deal
Wed, 30 Apr - Wed, 7 May
British Airways Logo
09:50 - 16:59LHR-SEA
15h 09m1 stop
British Airways Logo
13:30 - 06:50SEA-LHR
9h 20mdirect
£482British Airways
Find Deal
Wed, 14 May - Thu, 22 May
KLM Logo
09:55 - 16:00LHR-SEA
14h 05m1 stop
KLM Logo
13:30 - 09:50SEA-LHR
12h 20m1 stop
£492KLM
Find Deal
Mon, 28 Apr - Tue, 13 May

United Airlines flights from London Heathrow Airport to Seattle

Our best United Airlines deals on London Heathrow Airport to Seattle flight tickets
United Airlines
29 Apr
LHR06:50London Heathrow
23h 53m
2 stops
SEA22:43Seattle/Tacoma Intl
13 May
SEA06:15Seattle/Tacoma Intl
21h 20m
2 stops
LHR11:35London Heathrow
United Airlines
28 Apr
LHR12:05London Heathrow
17h 36m
1 stop
SEA21:41Seattle/Tacoma Intl
13 May
SEA06:15Seattle/Tacoma Intl
21h 20m
2 stops
LHR11:35London Heathrow
United Airlines
14 May
LHR08:00London Heathrow
22h 50m
2 stops
SEA22:50Seattle/Tacoma Intl
22 May
SEA06:25Seattle/Tacoma Intl
20h 45m
1 stop
LHR11:10London Heathrow

Lufthansa flights from London Heathrow Airport to Seattle

Our best Lufthansa deals on London Heathrow Airport to Seattle flight tickets
Lufthansa
25 Apr
LHR14:10London Heathrow
12h 18m
1 stop
SEA18:28Seattle/Tacoma Intl
27 Apr
SEA07:00Seattle/Tacoma Intl
15h 20m
1 stop
LHR06:20London Heathrow
Lufthansa
14 May
LHR10:50London Heathrow
14h 09m
1 stop
SEA16:59Seattle/Tacoma Intl
21 May
SEA18:50Seattle/Tacoma Intl
14h 15m
1 stop
LHR17:05London Heathrow
Lufthansa
30 Apr
LHR14:50London Heathrow
14h 12m
1 stop
SEA21:02Seattle/Tacoma Intl
7 May
SEA15:25Seattle/Tacoma Intl
12h 55m
1 stop
LHR12:20London Heathrow

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 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 £492, are often lower during this time because this is during the off-season. The month of November is another great option to travel to Seattle, with average flight prices from London Heathrow Airport averaging around £519.

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

According to our data, Tuesday is the cheapest day to fly to Seattle from London Heathrow Airport. The lowest ticket price found for a Tuesday departure recently was £623. 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 £751.

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 £533. 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 £677.

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 24 weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around £592 when searching 24 weeks out.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 £529 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.

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

As of April 2025, prices for London Heathrow Airport to Seattle flights are approximately 9% more expensive 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

£257

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 £257. The best return flight deal from London Heathrow Airport to Seattle found on momondo in the last 72 hours is £313.
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)

  • 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 9h 45m.

  • 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
Aer LingusPriceFrom £8Free CancellationRating
7.0
1,063 reviews
Search Aer Lingus flights
IcelandairPriceFrom £373Free CancellationRating
7.0
484 reviews
Search Icelandair flights
Air FrancePriceFrom £391Free CancellationRating
7.5
1,435 reviews
Search Air France flights
LufthansaPriceFrom £401Free CancellationRating
6.7
7,012 reviews
Search Lufthansa flights
United AirlinesPriceFrom £404Free CancellationRating
7.4
8,667 reviews
Search United Airlines flights
KLMPriceFrom £413Free CancellationRating
7.8
1,329 reviews
Search KLM flights
FinnairPriceFrom £418Free CancellationRating
7.6
1,269 reviews
Search Finnair flights
British AirwaysPriceFrom £438Free CancellationRating
6.6
6,771 reviews
Search British Airways flights
DeltaPriceFrom £451Free CancellationRating
8.0
7,917 reviews
Search Delta flights
Virgin AtlanticPriceFrom £457Free CancellationRating
7.4
642 reviews
Search Virgin Atlantic 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 £826, but momondo users have found Delta deals from London Heathrow Airport to Seattle from as low as £597 round-trip. Delta has been scored 8.0/10 in 7,917 reviews.

  • KLM Flights From London Heathrow Airport to Seattle

    KLM (7.8/10 from 1,329 reviews) operates around 12 flights from London Heathrow Airport to Seattle in any given week. The average KLM airfare for this route is around £783, with deals from around £546 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
Kent
Tukwila
SeaTac
Fife
Mukilteo
Renton

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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