Cheap flights from London to Seattle from $517

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 1/11. 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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Cheap round-trip flights

Enter your travel dates to find the best prices.
Icelandair Logo
3:40 pm - 8:40 pm
LGW
-
SEA
13h 00m1 stop
Icelandair Logo
3:40 pm - 2:40 pm
SEA
-
LGW
15h 00m1 stop
$557Icelandair
Fri, Apr 10 - Mon, Apr 20
United Airlines Logo
12:05 pm - 4:01 pm
LHR
-
SEA
35h 56m2 stops
United Airlines Logo
8:10 am - 7:30 am
SEA
-
LHR
39h 20m2 stops
$557United Airlines
Thu, Jan 8 - Thu, Jan 15
Air Canada Logo
1:00 pm - 9:15 am
LHR
-
SEA
28h 15m2 stops
Air Canada Logo
9:55 am - 10:10 am
SEA
-
LHR
16h 15m2 stops
$558Air Canada
Thu, Jan 22 - Mon, Jan 26
Delta Logo
8:00 pm - 11:19 am
LHR
-
SEA
23h 19m1 stop
Delta Logo
7:30 am - 6:50 am
SEA
-
LHR
15h 20m1 stop
$560Delta
Wed, Jan 7 - Wed, Mar 4
Virgin Atlantic Logo
8:05 pm - 11:50 am
LCY
-
SEA
23h 45m1 stop
Virgin Atlantic Logo
3:10 pm - 4:35 pm
SEA
-
LCY
17h 25m1 stop
$561Virgin Atlantic
Mon, Jan 12 - Mon, Jan 26
American Airlines Logo
11:30 am - 11:05 pm
LHR
-
SEA
19h 35m2 stops
American Airlines Logo
3:57 pm - 2:25 pm
SEA
-
LHR
14h 28m1 stop
$561American Airlines
Wed, Apr 29 - Wed, May 13
British Airways Logo
10:00 pm - 4:59 pm
LHR
-
SEA
26h 59m1 stop
British Airways Logo
1:35 pm - 6:50 am
SEA
-
LHR
9h 15mnonstop
$567British Airways
Sun, Apr 5 - Thu, Apr 16
Virgin Atlantic Logo
8:05 pm - 4:58 pm
LCY
-
SEA
28h 53m2 stops
Virgin Atlantic Logo
3:10 pm - 5:20 pm
SEA
-
LCY
18h 10m1 stop
$567Virgin Atlantic
Mon, Jan 12 - Mon, Jan 26
Delta Logo
10:00 am - 4:30 pm
LCY
-
SEA
14h 30m1 stop
Delta Logo
5:30 pm - 4:40 pm
SEA
-
LCY
15h 10m1 stop
$575Delta
Wed, Apr 15 - Wed, Apr 29
British Airways Logo
5:15 pm - 7:20 pm
LCY
-
SEA
33h 05m1 stop
British Airways Logo
7:15 am - 8:50 am
SEA
-
LCY
42h 35m2 stops
$593British Airways
Tue, Mar 10 - Tue, Mar 17

Lufthansa flights from London to Seattle

Our best Lufthansa deals on London to Seattle flight tickets
Lufthansa
Mar 2
LHR6:30 amLondon Heathrow
13h 40m
1 stop
SEA12:10 pmSeattle/Tacoma Intl
Mar 13
SEA4:10 pmSeattle/Tacoma Intl
13h 50m
1 stop
LHR1:00 pmLondon Heathrow
Lufthansa
May 25
LHR6:30 amLondon Heathrow
13h 50m
1 stop
SEA12:20 pmSeattle/Tacoma Intl
Jun 1
SEA4:30 pmSeattle/Tacoma Intl
16h 05m
2 stops
LHR4:35 pmLondon Heathrow
Lufthansa
Apr 5
LCY6:30 pmLondon City
25h 50m
1 stop
SEA12:20 pmSeattle/Tacoma Intl
Apr 18
SEA2:10 pmSeattle/Tacoma Intl
19h 45m
1 stop
LCY5:55 pmLondon City

United Airlines flights from London to Seattle

Our best United Airlines deals on London to Seattle flight tickets
United Airlines
Mar 1
LHR9:30 amLondon Heathrow
19h 31m
2 stops
SEA9:01 pmSeattle/Tacoma Intl
Mar 13
SEA11:59 pmSeattle/Tacoma Intl
27h 16m
1 stop
LHR10:15 amLondon Heathrow
United Airlines
Apr 18
LHR3:05 pmLondon Heathrow
12h 13m
1 stop
SEA7:18 pmSeattle/Tacoma Intl
Apr 30
SEA12:51 pmSeattle/Tacoma Intl
15h 29m
1 stop
LHR12:20 pmLondon Heathrow
United Airlines
May 2
LHR9:30 amLondon Heathrow
18h 07m
1 stop
SEA7:37 pmSeattle/Tacoma Intl
May 13
SEA5:07 amSeattle/Tacoma Intl
23h 13m
1 stop
LHR12:20 pmLondon Heathrow

momondo Fare Finder

 
Customize 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 832,500 searches. Data last updated December 23, 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 4/10

3:40 pm-8:40 pm

1 stop13h 00m

Seattle/Tacoma Intl

Mon 4/20

3:40 pm-2:40 pm

1 stop15h 00m

$557

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Thu 1/8

12:05 pm-4:01 pm

2 stops35h 56m

Seattle/Tacoma Intl

Thu 1/15

8:10 am-7:30 am

2 stops39h 20m

$557

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Thu 1/22

1:00 pm-9:15 am

2 stops28h 15m

Seattle/Tacoma Intl

Mon 1/26

9:55 am-10:10 am

2 stops16h 15m

$558

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 1/7

8:00 pm-11:19 am

1 stop23h 19m

Seattle/Tacoma Intl

Wed 3/4

7:30 am-6:50 am

1 stop15h 20m

$560

LondonSeattle

LCY - SEA

LCYSEA

London City

Mon 1/12

8:05 pm-11:50 am

1 stop23h 45m

Seattle/Tacoma Intl

Mon 1/26

3:10 pm-4:35 pm

1 stop17h 25m

$561

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 4/29

11:30 am-11:05 pm

2 stops19h 35m

Seattle/Tacoma Intl

Wed 5/13

3:57 pm-2:25 pm

1 stop14h 28m

$561

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Sun 4/5

10:00 pm-4:59 pm

1 stop26h 59m

Seattle/Tacoma Intl

Thu 4/16

1:35 pm-6:50 am

Nonstop9h 15m

$567

LondonSeattle

LCY - SEA

LCYSEA

London City

Mon 1/12

8:05 pm-4:58 pm

2 stops28h 53m

Seattle/Tacoma Intl

Mon 1/26

3:10 pm-5:20 pm

1 stop18h 10m

$567

LondonSeattle

LCY - SEA

LCYSEA

London City

Wed 4/15

10:00 am-4:30 pm

1 stop14h 30m

Seattle/Tacoma Intl

Wed 4/29

5:30 pm-4:40 pm

1 stop15h 10m

$575

LondonSeattle

LCY - SEA

LCYSEA

London City

Tue 3/10

5:15 pm-7:20 pm

1 stop33h 05m

Seattle/Tacoma Intl

Tue 3/17

7:15 am-8:50 am

2 stops42h 35m

$593

Flights are sorted by cheapest round-trip 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?

In general, February is the cheapest month to fly from London to Seattle. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $648. If you don’t want to visit Seattle in February, then you should wait until January to fly from London, when ticket prices are also cheap, with an average price of $649.

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

On average, the least expensive day to fly to Seattle from London is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as $759. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Friday is the most expensive day to depart from London because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $958.

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

Flying to Seattle from London in the afternoon is the least expensive time of day to depart. momondo users have found prices as low as $819 when looking at flights departing in the afternoon. Flights to Seattle are more costly at noon, with an average ticket price of $862. Departure times at noon fall within the peak daily travel times, which is why tickets can be more expensive.

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 $761 when searching 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 $699 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 7% 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 15% 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 round-trip 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

$596

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 $596. The best round-trip flight deal from London to Seattle found on momondo in the last 72 hours is $700.
The fastest flight from London to Seattle takes 9h 45m
Direct flights go from London to Seattle every day.
There is 1 airport in Seattle. From London there are direct flights to Seattle/Tacoma Intl (SEA).
  • How far is London to Seattle/Tacoma Intl by plane?

    The straight-line distance from London to Seattle/Tacoma Intl is 4781.3 mi. Flights usually cover this in 9h 45m, depending on flying conditions and air traffic around both airports.

  • 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 refreshed on a daily basis.

  • 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 a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to 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 $418Free CancellationRating
7.0
592 reviews
Search Icelandair flights
British AirwaysPriceFrom $553Free CancellationRating
6.7
7,607 reviews
Search British Airways flights
Virgin AtlanticPriceFrom $574Free CancellationRating
7.5
677 reviews
Search Virgin Atlantic flights
DeltaPriceFrom $575Free CancellationRating
7.9
8,015 reviews
Search Delta flights
American AirlinesPriceFrom $589Free CancellationRating
7.2
11,050 reviews
Search American Airlines flights
  • Delta Flights From London to Seattle

    Across 10 Delta flights from London to Seattle this week, the average price was $860, with the best Delta deals starting from $575 round-trip. 8,014 users have rated Delta on momondo, with an average score of 7.9/10.

  • Virgin Atlantic Flights From London to Seattle

    Virgin Atlantic is also a popular choice for this route. Virgin Atlantic flight deals for London to Seattle start from as low as $574 round-trip, depending on your selected dates, with average Virgin Atlantic deals seen on momondo around $772. Virgin Atlantic operates 10 flights to Seattle from London in an average week. Users have rated it 7.5/10 across 677 reviews.

Traveling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Tacoma
Leavenworth
SeaTac
Ocean Shores
Renton
Olympia
Lynnwood
Kent
Marysville
Puyallup
Redmond
Tukwila
Cle Elum
Federal Way
Lakewood
Fife
Centralia
Westport
Kirkland
Shoreline

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?

momondo provides multiple filters to help you find the best flight to Seattle from London. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.

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

If you are simply researching potential flights to Seattle, momondo offers a useful price alert feature which will track prices for flights to Seattle from London and alert you when they change.

An easier way to manage your Seattle trip

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1 adult
Thu 1/22
Thu 1/29

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