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Cheap flights from London Heathrow Airport to Seattle from £390

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 1/10. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — SEA
23 Aug — 30 Aug1
1 adult

Cheapflights Tip: The best prices from London Heathrow to Seattle/Tacoma Intl are usually found in February or November, booked 62 days in advance, depart on a Wednesday or Tuesday and return on a Tuesday

Cheap flight deals from Heathrow to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Heathrow (LHR) to Seattle (SEA). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated 18 August 2025.

Round-trip from

£473

One-way from

£392

Popular in

July

Cheapest in

February

Average price

£667

Good round-trip deal

£539 or less

Good one-way deal

£633 or less
Virgin Atlantic
  • Virgin Atlantic
  • 9/9-16/9
  • 1 total stop
  • 29h 15m total
  • London to Seattle
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12/9
  • 12/9
  • 3 total stops
  • 23h 36m total
  • London to Seattle
Search Deals
Highest demand for flights based on searches. 12% potential increase in price (£60 potential increase over avg. return price).
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Cheapest flight prices on average. 2% potential price decrease (£10 potential savings vs. average return price).
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Average for round-trip flights in August 2025
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Price to beat on a round-trip flight from London Heathrow to Seattle/Tacoma Intl.
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Price to beat on a one-way flight from London Heathrow to Seattle/Tacoma Intl.
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Find flight deals from Heathrow to Seattle

Cheapest flights from Heathrow to Seattle
Explore the most affordable flight options available from Heathrow to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 18 August 2025.

Tue 9/906:15LHR - SEA
1 stop19h 25mVirgin Atlantic
Tue 16/920:25SEA - LHR
Nonstop9h 50mVirgin Atlantic
Deal found 16/8£473
Tue 2/1206:20LHR - SEA
1 stop13h 05mVirgin Atlantic
Tue 9/1216:45SEA - LHR
Nonstop9h 45mVirgin Atlantic
Deal found 17/8£474
Wed 3/910:50LHR - SEA
1 stop14h 09mUnited Airlines
Thu 11/908:00SEA - LHR
2 stops19h 45mUnited Airlines
Deal found 15/8£474
Thu 4/909:30LHR - SEA
2 stops19h 24mUnited Airlines
Sat 13/911:11SEA - LHR
1 stop17h 09mUnited Airlines
Deal found 15/8£475
Sat 27/906:30LHR - SEA
2 stops15h 46mMultiple Airlines
Sat 4/1005:30SEA - LHR
2 stops17h 00mMultiple Airlines
Deal found 17/8£476
Mon 15/908:40LHR - SEA
2 stops17h 56mMultiple Airlines
Mon 15/1210:05SEA - LHR
2 stops16h 40mMultiple Airlines
Deal found 16/8£477
Mon 29/914:10LHR - SEA
1 stop16h 06mAir Canada
Tue 14/1010:00SEA - LHR
2 stops15h 35mAir Canada
Deal found 17/8£478
Thu 2/1013:05LHR - SEA
1 stop15h 35mIcelandair
Sun 12/1015:45SEA - LHR
1 stop12h 10mIcelandair
Deal found 16/8£479
Mon 22/913:25LHR - SEA
Nonstop10h 05mVirgin Atlantic
Mon 6/1017:35SEA - LHR
Nonstop9h 45mVirgin Atlantic
Deal found 17/8£479
Wed 27/807:30LHR - SEA
2 stops18h 27mUnited Airlines
Wed 10/905:02SEA - LHR
2 stops17h 43mUnited Airlines
Deal found 17/8£480
Mon 15/913:25LHR - SEA
Nonstop10h 05mVirgin Atlantic
Mon 6/1013:35SEA - LHR
1 stop15h 35mVirgin Atlantic
Deal found 16/8£481

Cheapflights Fare Finder

 
Customise your flight search to find flights from Heathrow 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, Cheapflights users made 858,174 searches. Data last updated 18 August 2025.
Use the filters below to find and compare flights from London Heathrow Airport to Seattle that are best for you.

Fly from

Heathrow

Fly to

Seattle

Route

Depart

Return

Price

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 19/9

06:30-14:16

2 stops15h 46m

Seattle/Tacoma Intl

Sun 21/9

07:15-09:35

1 stop18h 20m

£474

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 6/10

06:30-11:55

1 stop13h 25m

Seattle/Tacoma Intl

Mon 20/10

23:40-06:20

1 stop22h 40m

£474

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 3/9

10:50-16:59

1 stop14h 09m

Seattle/Tacoma Intl

Sun 14/9

07:10-11:45

2 stops20h 35m

£474

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 1/10

06:55-16:59

1 stop18h 04m

Seattle/Tacoma Intl

Wed 8/10

14:55-13:20

1 stop14h 25m

£474

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 30/9

06:30-11:55

1 stop13h 25m

Seattle/Tacoma Intl

Tue 7/10

07:00-11:45

1 stop20h 45m

£474

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 12/9

06:55-16:59

1 stop18h 04m

Seattle/Tacoma Intl

Mon 15/9

07:10-08:20

2 stops17h 10m

£474

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 3/9

10:50-16:59

1 stop14h 09m

Seattle/Tacoma Intl

Thu 11/9

08:00-11:45

2 stops19h 45m

£474

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 19/9

06:30-11:55

1 stop13h 25m

Seattle/Tacoma Intl

Sun 21/9

23:10-20:40

1 stop13h 30m

£474

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 5/11

07:40-13:20

1 stop13h 40m

Seattle/Tacoma Intl

Sun 9/11

20:00-10:10

2 stops30h 10m

£475

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Sat 27/9

06:30-14:16

2 stops15h 46m

Seattle/Tacoma Intl

Sat 4/10

07:15-09:35

1 stop18h 20m

£476

Flights are sorted by cheapest return flights first.

Deals found on 15/8

Showing 1-10 of 22 results
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Best time to book a flight from Heathrow to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Heathrow with our price prediction graph.
Estimated return price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from London Heathrow Airport to Seattle

How far ahead should I book a flight from London Heathrow Airport to Seattle?

Use this chart to determine the optimal time to book a return flight from Heathrow to Seattle. Price data was last updated on 8 August 2025.

The best time to book flights from London Heathrow Airport to Seattle is 62 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from London Heathrow Airport to Seattle?

Currently, January is the cheapest month in which you can book a flight from London Heathrow Airport to Seattle (average of £622). Flying from London Heathrow Airport to Seattle in July is currently the most expensive (average of £946). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from LHR to SEA?

Find hourly flight availability from Heathrow to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 18 August 2025.

It’s typically best to fly out from London Heathrow Airport to Seattle in the evening. Doing so could potentially save you 18% on the flight price compared to flying in the afternoon, which is usually more expensive.

What is the cheapest day to fly from London Heathrow Airport to Seattle?

Use this chart to determine the cheapest time to fly return from Heathrow to Seattle. Price data was last updated on 10 August 2025.

Travellers seeking maximum savings on their London Heathrow Airport to Seattle flight should consider departing on Monday evenings when fares are most often at their lowest. Sunday at midday flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from London Heathrow Airport to Seattle

Explore weekly flight availability from Heathrow to Seattle. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated 18 August 2025.

The most flights from LHR to SEA are scheduled on a Monday (21 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (10 on average).

What’s the top stopover airport for flights from London Heathrow Airport to Seattle?

Share of one-stop return flights from London Heathrow Airport to Seattle chosen by Cheapflights users in the past 12 months, using the same stopover each way.

Reykjavik (KEF) – chosen by Cheapflights users on 65% of one-stop itineraries from London Heathrow Airport to Seattle on Cheapflights.

What’s the cheapest stopover airport for flights from London Heathrow Airport to Seattle?

Average return fare for one-stop flights from London Heathrow Airport to Seattle, chosen by Cheapflights users in the past 12 months, with the same stopover each way.

Zurich (ZRH) is the most affordable one-stop option, with an average return flight price of £430.

What’s the fastest stopover option from London Heathrow Airport to Seattle?

Shortest average travel time for one-stop one-way flights from London Heathrow Airport to Seattle, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by stopover airport.

Flights via Dublin (DUB) have the shortest average one-way travel time for one-stop routes: 13h 11m.

Which airport typically offers the quickest stopover for flights from London Heathrow Airport to Seattle?

Average stopover duration for one-stop one-way flights from London Heathrow Airport to Seattle, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Denver (DEN) offer the fastest connection on this route, with an average stopover time of 1h 35m.

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Seattle. Reviews last updated 18 August 2025.
See what other customers who have flown with KLM, Air France, andVirgin Atlantic from London Heathrow Airport to Seattle have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
KLM
7.8
Good
1,385 reviews
Check prices

Crew

8.4

Food

7.3

Entertainment

7.1

Comfort

7.7

Boarding

7.8

Overall

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Jun 2025

AMS - BOS

A two and half hour delay caused havoc with all connections. Otherwise on board service was great.
KLM
7.8
Good
1,385 reviews
KLM
7.8
Good
1,385 reviews
Check prices

Crew

8.4

Food

7.3

Entertainment

7.1

Comfort

7.7

Boarding

7.8

Overall

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Jun 2025

AMS - BOS

A two and half hour delay caused havoc with all connections. Otherwise on board service was great.
Air France
7.4
Good
1,468 reviews
KLM
7.8
Good
1,385 reviews
Check prices

Crew

8.4

Food

7.3

Entertainment

7.1

Comfort

7.7

Boarding

7.8

Overall

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Jun 2025

AMS - BOS

A two and half hour delay caused havoc with all connections. Otherwise on board service was great.
Virgin Atlantic
7.4
Good
657 reviews
KLM
7.8
Good
1,385 reviews
Check prices

Crew

8.4

Food

7.3

Entertainment

7.1

Comfort

7.7

Boarding

7.8

Overall

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Jun 2025

AMS - BOS

A two and half hour delay caused havoc with all connections. Otherwise on board service was great.
Icelandair
7.0
Good
527 reviews
KLM
7.8
Good
1,385 reviews
Check prices

Crew

8.4

Food

7.3

Entertainment

7.1

Comfort

7.7

Boarding

7.8

Overall

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Jun 2025

AMS - BOS

A two and half hour delay caused havoc with all connections. Otherwise on board service was great.
British Airways
6.7
Okay
7,277 reviews
KLM
7.8
Good
1,385 reviews
Check prices

Crew

8.4

Food

7.3

Entertainment

7.1

Comfort

7.7

Boarding

7.8

Overall

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Jun 2025

AMS - BOS

A two and half hour delay caused havoc with all connections. Otherwise on board service was great.

Related info for your journey

Find useful and relevant information for your journey from Heathrow to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Seattle from London Heathrow?

    If you book a flight to Seattle from London Heathrow, you will be flying to Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 18 flights from London Heathrow to Seattle/Tacoma Intl per day from 13 different airlines.

  • What are the cheapest airlines flying from London Heathrow Airport to Seattle round-trip?

    According to our current data, Aer Lingus (£7), Icelandair (£351), and Air France (£381) offers the cheapest pricing from London Heathrow Airport to Seattle. Aer Lingus is priced at 98% lower than the current average price of a flight leaving 3 months from now.

  • What are the most reliable airlines from London Heathrow Airport to Seattle?

    Consider Scandinavian Airlines (95%), KLM (90%) or Air France (90%) when booking your flight. These represent the most reliable airlines when flying from London Heathrow Airport to Seattle.

  • What are the cheapest flights from London Heathrow Airport to Seattle?

    The cheapest flight price from London Heathrow Airport to Seattle is £473. On average you can expect to pay £1,540. The most popular route, (London Heathrow - Seattle/Tacoma Intl), can usually be booked for £390.

  • Can I find deals for flights from Heathrow to Seattle that include hotel bookings?

    Yes. In addition to deals on Heathrow to Seattle flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Heathrow to Seattle?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Heathrow to Seattle.

  • Can I find deals for business class flights from Heathrow to Seattle?

    Yes. Cheapflights offers flight deals from Heathrow to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from London Heathrow Airport to Seattle?

    Currently, January is the cheapest month in which you can book a flight from London Heathrow Airport to Seattle (average of £622). Flying from London Heathrow Airport to Seattle in July is currently the most expensive (average of £946). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Travelling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Tacoma
Leavenworth
Bothell
SeaTac

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Fly from Heathrow to Seattle on these airlines

Choose from the following airlines for your flight from Heathrow to Seattle. Flights are based on user searches made on Cheapflights and were last updated on 18 August 2025.
Virgin Atlantic flights from London Heathrow to Seattle/Tacoma Intl
British Airways flights from London Heathrow to Seattle/Tacoma Intl
Finnair flights from London Heathrow to Seattle/Tacoma Intl

Top 10 airlines flying from Heathrow to Seattle

Discover the top 10 airlines that operate flights from Heathrow to Seattle. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 858,174 searches. Data last updated 18 August 2025.
AirlineCheapestAverageFlexibilityOn-time
IcelandairCheapest£352Average£466FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
Air FranceCheapest£381Average£568FlexibilityNo cancel feeOn-time77%
Search Air France flights
LufthansaCheapest£391Average£490FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
FinnairCheapest£400Average£545FlexibilityNo cancel feeOn-time76%
Search Finnair flights
KLMCheapest£400Average£562FlexibilityNo cancel feeOn-time75%
Search KLM flights
United AirlinesCheapest£401Average£636FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
British AirwaysCheapest£427Average£583FlexibilityNo cancel feeOn-time70%
Search British Airways flights
Virgin AtlanticCheapest£439Average£573FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
DeltaCheapest£440Average£571FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
Air CanadaCheapest£459Average£557FlexibilityNo cancel feeOn-time67%
Search Air Canada flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Heathrow to Seattle?

Deals for Heathrow to Seattle flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from Heathrow to Seattle?

Cheapflights helps you find that perfect flight to Seattle from Heathrow by searching from hundreds of airlines and agencies you know and love. We are also free to use, in case you were wondering!

Can Cheapflights find flights from Heathrow to Seattle with no change fees?

Need flexible booking options for your flight to Seattle from Heathrow? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

Can Cheapflights notify me if prices for flights from Heathrow to Seattle become cheaper?

Yes! Start tracking prices for Heathrow to Seattle flights today and get alerted whenever prices for these flights change. To access this feature, click the bell icon next to the flight deals above, which will prompt you for a valid email address to receive your alerts.

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