Latest deals
Insights
When to book
FAQs
Reviews
Price Alerts

Cheap flights from London Heathrow Airport to Seattle from £312

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 13/10. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

Discover deals from 900+ travel sites with momondo.

Voted winner of Europe's Best Travel App 2023

Save money when you book flights with momondo

Big names, great deals

Big names, great deals

Search 100s of travel sites to compare prices.

Filter for what you want

Filter for what you want

Free Wi-Fi? Stopover? Instantly customise your results.

Trusted and free

Trusted and free

We’re completely free to use - no hidden charges or fees.

Price Alerts

Price Alerts

Not ready to book? to track prices.

Find the cheapest flights from London Heathrow Airport to Seattle

Cheap return flights

Icelandair Logo
21:25 - 20:40LHR-SEA
31h 15m1 stop
Icelandair Logo
19:00 - 11:55SEA-LHR
32h 55m1 stop
£399Icelandair
Find Deal
Tue, 14 Oct - Tue, 21 Oct
Icelandair Logo
13:05 - 20:40LHR-SEA
15h 35m1 stop
Icelandair Logo
19:00 - 11:55SEA-LHR
32h 55m1 stop
£408Icelandair
Find Deal
Thu, 18 Sep - Sat, 27 Sep
Icelandair Logo
21:25 - 11:25LHR-SEA
22h 00m1 stop
Icelandair Logo
19:00 - 11:55SEA-LHR
32h 55m1 stop
£413Icelandair
Find Deal
Mon, 25 Aug - Wed, 10 Sep
Icelandair Logo
21:25 - 11:25LHR-SEA
22h 00m1 stop
Icelandair Logo
15:45 - 11:55SEA-LHR
12h 10m1 stop
£416Icelandair
Find Deal
Sat, 6 Sep - Sat, 4 Oct
Icelandair Logo
21:25 - 11:25LHR-SEA
22h 00m1 stop
Icelandair Logo
15:45 - 11:55SEA-LHR
12h 10m1 stop
£418Icelandair
Find Deal
Sat, 13 Sep - Fri, 19 Sep
Scandinavian Airlines Logo
18:05 - 13:50LHR-SEA
51h 45m2 stops
Scandinavian Airlines Logo
16:20 - 09:20SEA-LHR
33h 00m1 stop
£423Scandinavian Airlines
Find Deal
Mon, 8 Sep - Sun, 5 Oct
Lufthansa Logo
07:25 - 16:59LHR-SEA
17h 34m1 stop
Lufthansa Logo
14:20 - 20:40SEA-LHR
22h 20m1 stop
£436Lufthansa
Find Deal
Fri, 12 Sep - Tue, 23 Sep
Lufthansa Logo
07:25 - 16:59LHR-SEA
17h 34m1 stop
Lufthansa Logo
14:20 - 14:40SEA-LHR
16h 20m1 stop
£441Lufthansa
Find Deal
Fri, 12 Sep - Wed, 24 Sep
Air Canada Logo
08:40 - 19:31LHR-SEA
18h 51m2 stops
Air Canada Logo
07:15 - 06:30SEA-LHR
15h 15m1 stop
£467Air Canada
Find Deal
Fri, 12 Sep - Tue, 23 Sep
United Airlines Logo
09:00 - 16:59LHR-SEA
15h 59m1 stop
United Airlines Logo
07:10 - 08:20SEA-LHR
17h 10m2 stops
£470United Airlines
Find Deal
Fri, 12 Sep - Wed, 24 Sep

Icelandair flights from London Heathrow Airport to Seattle

Our best Icelandair deals on London Heathrow Airport to Seattle flight tickets
Icelandair
14 Oct
LHR21:25London Heathrow
31h 15m
1 stop
SEA20:40Seattle/Tacoma Intl
21 Oct
SEA19:00Seattle/Tacoma Intl
32h 55m
1 stop
LHR11:55London Heathrow
Icelandair
18 Sept
LHR13:05London Heathrow
15h 35m
1 stop
SEA20:40Seattle/Tacoma Intl
27 Sept
SEA19:00Seattle/Tacoma Intl
32h 55m
1 stop
LHR11:55London Heathrow
Icelandair
25 Aug
LHR21:25London Heathrow
22h 00m
1 stop
SEA11:25Seattle/Tacoma Intl
10 Sept
SEA19:00Seattle/Tacoma Intl
32h 55m
1 stop
LHR11:55London Heathrow

Air Canada flights from London Heathrow Airport to Seattle

Our best Air Canada deals on London Heathrow Airport to Seattle flight tickets
Air Canada
12 Sept
LHR08:40London Heathrow
18h 51m
2 stops
SEA19:31Seattle/Tacoma Intl
23 Sept
SEA07:15Seattle/Tacoma Intl
15h 15m
1 stop
LHR06:30London Heathrow
Air Canada
8 Jul
LHR14:05London Heathrow
14h 36m
1 stop
SEA20:41Seattle/Tacoma Intl
19 Jul
SEA19:15Seattle/Tacoma Intl
27h 15m
2 stops
LHR06:30London 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 £480, 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 £504.

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 £587. 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 £711.

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 morning are often more expensive, with an average ticket price of £632.

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 £570 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 £512 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 July 2025, prices for London Heathrow Airport to Seattle flights are approximately 1% 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

£312

Fastest flight time

12h 25m

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 £312. The best return flight deal from London Heathrow Airport to Seattle found on momondo in the last 72 hours is £399.
The fastest flight from London Heathrow Airport to Seattle takes 12h 25m
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 12h 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 £7Free CancellationRating
7.1
1,144 reviews
Search Aer Lingus flights
IcelandairPriceFrom £349Free CancellationRating
7.0
514 reviews
Search Icelandair flights
Air FrancePriceFrom £379Free CancellationRating
7.5
1,473 reviews
Search Air France flights
LufthansaPriceFrom £385Free CancellationRating
6.8
7,207 reviews
Search Lufthansa flights
United AirlinesPriceFrom £386Free CancellationRating
7.4
8,845 reviews
Search United Airlines flights
FinnairPriceFrom £397Free CancellationRating
7.6
1,304 reviews
Search Finnair flights
KLMPriceFrom £400Free CancellationRating
7.8
1,363 reviews
Search KLM flights
Air CanadaPriceFrom £414Free CancellationRating
7.1
9,659 reviews
Search Air Canada flights
British AirwaysPriceFrom £418Free CancellationRating
6.6
7,093 reviews
Search British Airways flights
Virgin AtlanticPriceFrom £435Free CancellationRating
7.4
654 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 £822, 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 7,982 reviews.

  • KLM Flights From London Heathrow Airport to Seattle

    KLM (7.8/10 from 1,367 reviews) operates around 12 flights from London Heathrow Airport to Seattle in any given week. The average KLM airfare for this route is around £770, with deals from around £545 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
SeaTac
Tukwila
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.


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.
1 adult
Wed 9/7
Wed 16/7

Find better results for your trip to the United States