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Cheap flights from London to Seattle from £247

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 9/5. 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 to Seattle

Cheap return flights

KAYAK's recommended return flight deals from the most popular airlines that fly from London to Seattle.
14:10 - 18:28LHR-SEA
12h 18m1 stop
17:13 - 06:30SEA-LHR
29h 17m2 stops
£326United Airlines
Find Deal
Mon, 21 Apr - Mon, 5 May
14:10 - 18:28LHR-SEA
12h 18m1 stop
17:13 - 06:30SEA-LHR
29h 17m2 stops
£327United Airlines
Find Deal
Mon, 21 Apr - Mon, 5 May
15:40 - 17:50LGW-SEA
34h 10m1 stop
15:45 - 14:40SEA-LGW
14h 55m1 stop
£366Icelandair
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Tue, 22 Apr - Tue, 29 Apr
15:40 - 20:40LGW-SEA
13h 00m1 stop
15:45 - 14:40SEA-LGW
14h 55m1 stop
£367Icelandair
Find Deal
Wed, 23 Apr - Tue, 29 Apr
12:00 - 16:59LHR-SEA
12h 59m1 stop
20:20 - 13:40SEA-LHR
9h 20mdirect
£450British Airways
Find Deal
Wed, 10 Sep - Wed, 24 Sep
20:55 - 11:45LHR-SEA
22h 50m1 stop
20:20 - 14:15SEA-LHR
9h 55mdirect
£469KLM
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Sun, 20 Apr - Tue, 29 Apr
06:30 - 15:57LHR-SEA
17h 27m1 stop
20:20 - 14:15SEA-LHR
9h 55mdirect
£470KLM
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Mon, 5 May - Wed, 14 May
08:50 - 16:59LHR-SEA
16h 09m1 stop
20:20 - 13:40SEA-LHR
9h 20mdirect
£475British Airways
Find Deal
Mon, 21 Apr - Mon, 28 Apr
13:25 - 15:45LHR-SEA
10h 20mdirect
17:35 - 11:20SEA-LHR
9h 45mdirect
£485Virgin Atlantic
Find Deal
Mon, 21 Apr - Mon, 5 May
13:25 - 15:45LHR-SEA
10h 20mdirect
22:59 - 20:00SEA-LHR
13h 01m1 stop
£490Virgin Atlantic
Find Deal
Mon, 21 Apr - Mon, 5 May

Icelandair flights from London to Seattle

Our best Icelandair deals on London to Seattle flight tickets
Icelandair
22 Apr
LGW15:40London Gatwick
34h 10m
1 stop
SEA17:50Seattle/Tacoma Intl
29 Apr
SEA15:45Seattle/Tacoma Intl
14h 55m
1 stop
LGW14:40London Gatwick
Icelandair
23 Apr
LGW15:40London Gatwick
13h 00m
1 stop
SEA20:40Seattle/Tacoma Intl
29 Apr
SEA15:45Seattle/Tacoma Intl
14h 55m
1 stop
LGW14:40London Gatwick
Icelandair
22 Apr
LGW15:40London Gatwick
13h 00m
1 stop
SEA20:40Seattle/Tacoma Intl
29 Apr
SEA19:00Seattle/Tacoma Intl
11h 40m
1 stop
LGW14:40London Gatwick

KLM flights from London to Seattle

Our best KLM deals on London to Seattle flight tickets
KLM
20 Apr
LHR20:55London Heathrow
22h 50m
1 stop
SEA11:45Seattle/Tacoma Intl
29 Apr
SEA20:20Seattle/Tacoma Intl
9h 55m
LHR14:15London Heathrow
KLM
5 May
LHR06:30London Heathrow
17h 27m
1 stop
SEA15:57Seattle/Tacoma Intl
14 May
SEA20:20Seattle/Tacoma Intl
9h 55m
LHR14:15London Heathrow
KLM
24 Apr
LHR06:30London Heathrow
13h 15m
1 stop
SEA11:45Seattle/Tacoma Intl
1 May
SEA20:20Seattle/Tacoma Intl
9h 55m
LHR14:15London Heathrow

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 £489, 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 £511.

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. The lowest ticket price found for a Tuesday departure recently was £637. 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 £768.

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 £546. 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 £693.

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 24 weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around £607 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 for as low as £566 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.

How have London to Seattle flight prices changed over time?

As of March 2025, prices for London to Seattle flights are approximately 7% 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

£247

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 £247. The best return flight deal from London to Seattle found on momondo in the last 72 hours is £326.
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
Aer LingusPriceFrom £8Free CancellationRating
7.0
1,062 reviews
Search Aer Lingus flights
IcelandairPriceFrom £338Free CancellationRating
7.0
474 reviews
Search Icelandair flights
Air FrancePriceFrom £400Free CancellationRating
7.4
1,423 reviews
Search Air France flights
LufthansaPriceFrom £410Free CancellationRating
6.7
6,950 reviews
Search Lufthansa flights
United AirlinesPriceFrom £421Free CancellationRating
7.4
8,608 reviews
Search United Airlines flights
KLMPriceFrom £422Free CancellationRating
7.8
1,319 reviews
Search KLM flights
FinnairPriceFrom £430Free CancellationRating
7.6
1,266 reviews
Search Finnair flights
DeltaPriceFrom £446Free CancellationRating
8.0
7,891 reviews
Search Delta flights
British AirwaysPriceFrom £450Free CancellationRating
6.6
6,712 reviews
Search British Airways flights
Virgin AtlanticPriceFrom £469Free CancellationRating
7.4
634 reviews
Search Virgin Atlantic flights
  • Delta Flights From London to Seattle

    Delta flight deals from London to Seattle start from £576 round-trip. Over the 5 Delta flights for this route in a normal week, average airfare is usually £826 round-trip - but some users have found much cheaper deals with momondo.

  • KLM Flights From London to Seattle

    KLM (7.8/10 from 1,319 reviews) operates around 5 flights from London to Seattle in any given week. The average KLM airfare for this route is around £791, with deals from around £546 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
Kent
Tukwila
SeaTac
Fife
Mukilteo
Renton

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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