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 9/12. Fares are subject to change and may not be available on all flights or dates of travel.
LON — SEA
14 Dec — 21 Dec1
Return
1 adult
Economy
Return
1 adult, Economy, 0 bags
Cheapflights Tip: The best prices from London to Seattle/Tacoma Intl are usually found in January or February, booked 90 days in advance, depart on a Wednesday or Tuesday and return on a Tuesday
Find flight deals from London to Seattle
Enter your travel dates to find the best prices.
Cheapest flights from London to Seattle
Explore the most affordable flight options available from London to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 14 November 2025.
Wed 19/1111:55LGW - SEA
1 stop13h 05mIcelandair
Wed 31/1214:35SEA - LGW
1 stop12h 20mIcelandair
Deal found 13/11£474
Wed 24/1211:55LGW - SEA
1 stop13h 05mIcelandair
Tue 6/114:35SEA - LGW
1 stop12h 20mIcelandair
Deal found 13/11£476
Sat 6/1211:55LGW - SEA
1 stop13h 05mIcelandair
Tue 6/114:35SEA - LGW
1 stop12h 20mIcelandair
Deal found 12/11£477
Thu 4/1220:35LHR - SEA
1 stop28h 25mIcelandair
Tue 6/114:35SEA - LHR
1 stop20h 55mIcelandair
Deal found 12/11£480
Sat 6/1212:15LHR - SEA
1 stop12h 45mIcelandair
Tue 6/114:35SEA - LHR
1 stop20h 55mIcelandair
Deal found 12/11£480
Tue 16/1220:35LHR - SEA
1 stop28h 25mIcelandair
Thu 15/114:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 13/11£482
Tue 16/1220:35LHR - SEA
1 stop28h 25mIcelandair
Mon 5/114:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 13/11£486
Tue 2/1220:35LHR - SEA
1 stop28h 25mIcelandair
Sat 6/1214:35SEA - LHR
1 stop20h 55mIcelandair
Deal found 13/11£489
Mon 8/1208:30STN - SEA
1 stop17h 50mMultiple Airlines
Sun 14/1220:05SEA - STN
1 stop12h 30mMultiple Airlines
Deal found 12/11£490
Sun 23/1120:35LHR - SEA
1 stop28h 25mIcelandair
Sun 30/1114:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 12/11£490
Mon 8/1209:40LGW - SEA
1 stop16h 40mMultiple Airlines
Sun 14/1220:05SEA - LGW
1 stop13h 05mMultiple Airlines
Deal found 12/11£494
Tue 18/1120:35LHR - SEA
1 stop28h 25mIcelandair
Wed 31/1214:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 12/11£496
Best flights from London to Seattle
Discover carefully curated flight deals from London to Seattle that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 14 November 2025.
Tue 16/1220:35LHR - SEA
1 stop28h 25mIcelandair
Thu 15/114:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 13/11£482
Fri 13/214:55LHR - SEA
Nonstop10h 00mBritish Airways
Thu 19/213:39SEA - LHR
1 stop13h 56mBritish Airways
Deal found 12/11£495
Wed 21/112:20LHR - SEA
Nonstop10h 33mDelta
Sat 24/122:59SEA - LHR
1 stop23h 26mDelta
Deal found 11/11£499
Tue 13/113:00LGW - SEA
1 stop29h 26mMultiple Airlines
Thu 29/123:10SEA - LGW
1 stop26h 50mMultiple Airlines
Deal found 13/11£511
Mon 2/208:40LCY - SEA
2 stops20h 06mVirgin Atlantic
Tue 10/207:10SEA - LCY
2 stops17h 00mVirgin Atlantic
Deal found 12/11£518
Mon 2/206:30LHR - SEA
1 stop13h 40mUnited Airlines
Tue 10/210:58SEA - LHR
1 stop16h 17mUnited Airlines
Deal found 12/11£526
Tue 5/506:15STN - SEA
1 stop19h 00mTurkish Airlines
Sat 9/519:10SEA - STN
1 stop31h 05mTurkish Airlines
Deal found 11/11£728
Tue 16/1220:35LHR - SEA
1 stop28h 25mIcelandair
Wed 14/114:35SEA - LHR
1 stop20h 55mIcelandair
Deal found 12/11£483
Thu 15/120:05LCY - SEA
1 stop23h 45mVirgin Atlantic
Thu 22/115:10SEA - LCY
1 stop17h 25mVirgin Atlantic
Deal found 11/11£519
Tue 3/306:30LHR - SEA
1 stop13h 40mUnited Airlines
Tue 10/308:30SEA - LHR
2 stops17h 40mUnited Airlines
Deal found 12/11£529
Mon 9/213:00LGW - SEA
1 stop33h 57mMultiple Airlines
Thu 12/214:44SEA - LGW
1 stop31h 16mMultiple Airlines
Deal found 13/11£542
Thu 27/1112:20LHR - SEA
Nonstop10h 28mDelta
Sun 30/1116:48SEA - LHR
Nonstop9h 42mDelta
Deal found 13/11£546
Thu 27/1112:15LHR - SEA
1 stop12h 45mIcelandair
Mon 1/1214:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 12/11£504
Tue 2/1206:30LHR - SEA
1 stop13h 40mUnited Airlines
Tue 9/1210:40SEA - LHR
2 stops16h 25mUnited Airlines
Deal found 12/11£541
Tue 2/1212:20LHR - SEA
Nonstop10h 38mDelta
Sat 6/1221:59SEA - LHR
1 stop14h 11mDelta
Deal found 13/11£546
Fri 13/320:05LCY - SEA
1 stop23h 30mVirgin Atlantic
Tue 14/415:35SEA - LCY
2 stops17h 05mVirgin Atlantic
Deal found 13/11£548
Tue 5/513:00LGW - SEA
1 stop12h 50mIcelandair
Sat 9/519:00SEA - LGW
1 stop11h 40mIcelandair
Deal found 11/11£524
Thu 4/1210:00LCY - SEA
1 stop33h 50mDelta
Mon 8/1215:05SEA - LCY
1 stop34h 25mDelta
Deal found 12/11£564
Sat 13/1210:45STN - SEA
3 stops43h 31mMultiple Airlines
Mon 5/114:35SEA - STN
2 stops20h 50mMultiple Airlines
Deal found 12/11£626
Thu 19/310:00LCY - SEA
2 stops19h 05mVirgin Atlantic
Sun 5/407:20SEA - LCY
2 stops17h 30mVirgin Atlantic
Deal found 13/11£571
Thu 19/310:00LCY - SEA
2 stops19h 00mVirgin Atlantic
Mon 6/409:55SEA - LCY
2 stops15h 35mVirgin Atlantic
Deal found 13/11£571
Fri 5/1214:00LGW - SEA
1 stop28h 37mMultiple Airlines
Sat 13/1214:43SEA - LGW
1 stop31h 17mMultiple Airlines
Deal found 12/11£636
Tue 16/1211:55LGW - SEA
1 stop13h 05mIcelandair
Wed 14/114:35SEA - LGW
1 stop12h 20mIcelandair
Deal found 12/11£612
Fri 5/1220:05LCY - SEA
1 stop23h 45mVirgin Atlantic
Sun 7/1215:05SEA - LCY
1 stop17h 30mVirgin Atlantic
Deal found 12/11£572
Thu 4/1214:00LGW - SEA
1 stop28h 37mMultiple Airlines
Tue 6/113:59SEA - LGW
1 stop32h 01mMultiple Airlines
Deal found 12/11£650
Thu 4/1209:20LCY - SEA
1 stop34h 30mVirgin Atlantic
Mon 8/1215:05SEA - LCY
1 stop19h 20mVirgin Atlantic
Deal found 11/11£574
Tue 16/1211:55LGW - SEA
1 stop13h 05mIcelandair
Thu 15/114:35SEA - LGW
1 stop12h 20mIcelandair
Deal found 13/11£655
Thu 19/318:10STN - SEA
2 stops32h 10mMultiple Airlines
Mon 6/418:45SEA - STN
1 stop20h 35mMultiple Airlines
Deal found 13/11£657
Sat 13/1207:20LTN - SEA
3 stops46h 56mMultiple Airlines
Mon 5/114:35SEA - LTN
2 stops17h 35mMultiple Airlines
Deal found 12/11£676
Tue 23/1220:50LTN - SEA
2 stops26h 50mMultiple Airlines
Mon 29/1217:40SEA - LTN
2 stops20h 50mMultiple Airlines
Deal found 12/11£695
Direct flights from London to Seattle
Explore direct flight options from London to Seattle based on user searches, and compare prices and availability for your desired travel dates. Data last updated 14 November 2025.
Fri 13/309:25LHR - SEA
Nonstop10h 05mBritish Airways
Tue 14/413:35SEA - LHR
Nonstop9h 15mBritish Airways
Deal found 13/11£473
Fri 13/214:55LHR - SEA
Nonstop10h 00mBritish Airways
Thu 19/218:50SEA - LHR
Nonstop9h 30mBritish Airways
Deal found 13/11£474
Tue 10/309:25LHR - SEA
Nonstop10h 05mBritish Airways
Tue 17/319:50SEA - LHR
Nonstop9h 30mBritish Airways
Deal found 13/11£476
Thu 15/112:20LHR - SEA
Nonstop10h 33mVirgin Atlantic
Thu 22/116:45SEA - LHR
Nonstop9h 45mVirgin Atlantic
Deal found 11/11£476
Thu 5/312:20LHR - SEA
Nonstop10h 25mVirgin Atlantic
Tue 10/320:20SEA - LHR
Nonstop9h 30mVirgin Atlantic
Deal found 13/11£482
Wed 8/409:50LHR - SEA
Nonstop9h 45mBritish Airways
Wed 15/413:35SEA - LHR
Nonstop9h 15mBritish Airways
Deal found 13/11£486
Tue 3/309:25LHR - SEA
Nonstop10h 05mBritish Airways
Tue 10/319:50SEA - LHR
Nonstop9h 30mBritish Airways
Deal found 12/11£490
Mon 2/212:20LHR - SEA
Nonstop10h 25mVirgin Atlantic
Tue 10/216:55SEA - LHR
Nonstop9h 35mVirgin Atlantic
Deal found 12/11£492
Fri 6/214:55LHR - SEA
Nonstop10h 00mBritish Airways
Sun 15/218:50SEA - LHR
Nonstop9h 30mBritish Airways
Deal found 13/11£492
Mon 2/214:55LHR - SEA
Nonstop10h 00mAmerican Airlines
Tue 10/218:50SEA - LHR
Nonstop9h 30mAmerican Airlines
Deal found 12/11£495
Thu 9/417:25LHR - SEA
Nonstop10h 20mVirgin Atlantic
Mon 13/415:35SEA - LHR
Nonstop9h 25mVirgin Atlantic
Deal found 13/11£502
Last-minute flights from London to Seattle
Discover last-minute flight deals from London to Seattle. Data last updated 14 November 2025 and is based on user searches.
Tue 18/1120:35LHR - SEA
1 stop28h 25mIcelandair
Wed 31/1214:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 12/11£496
Wed 19/1111:55LGW - SEA
1 stop13h 05mIcelandair
Wed 31/1214:35SEA - LGW
1 stop12h 20mIcelandair
Deal found 13/11£474
Sun 23/1120:35LHR - SEA
1 stop28h 25mIcelandair
Sun 30/1114:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 12/11£490
Tue 2/1220:35LHR - SEA
1 stop28h 25mIcelandair
Sat 6/1214:35SEA - LHR
1 stop20h 55mIcelandair
Deal found 13/11£489
Thu 4/1220:35LHR - SEA
1 stop28h 25mIcelandair
Tue 6/114:35SEA - LHR
1 stop20h 55mIcelandair
Deal found 12/11£480
Sat 6/1211:55LGW - SEA
1 stop13h 05mIcelandair
Tue 6/114:35SEA - LGW
1 stop12h 20mIcelandair
Deal found 12/11£477
Sat 6/1212:15LHR - SEA
1 stop12h 45mIcelandair
Tue 6/114:35SEA - LHR
1 stop20h 55mIcelandair
Deal found 12/11£480
Mon 8/1208:30STN - SEA
1 stop17h 50mMultiple Airlines
Sun 14/1220:05SEA - STN
1 stop12h 30mMultiple Airlines
Deal found 12/11£490
Mon 8/1209:40LGW - SEA
1 stop16h 40mMultiple Airlines
Sun 14/1220:05SEA - LGW
1 stop13h 05mMultiple Airlines
Deal found 12/11£494
Tue 16/1220:35LHR - SEA
1 stop28h 25mIcelandair
Thu 15/114:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 13/11£482
Tue 16/1220:35LHR - SEA
1 stop28h 25mIcelandair
Mon 5/114:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 13/11£486
Wed 24/1211:55LGW - SEA
1 stop13h 05mIcelandair
Tue 6/114:35SEA - LGW
1 stop12h 20mIcelandair
Deal found 13/11£476
One-way flights from London to Seattle
Search for one-way flight options from London to Seattle. Find affordable one-way fares based on user searches. Data last updated 14 November 2025.
Tue 9/1207:40LHR - SEA
2 stops19h 36mLufthansa
Deal found 11/11£416
Sun 8/214:55LHR - SEA
Nonstop10h 00mFinnair
Deal found 12/11£417
Mon 23/215:30LTN - SEA
1 stop33h 30mMultiple Airlines
Deal found 11/11£417
Wed 10/1213:00LGW - SEA
1 stop18h 19mMultiple Airlines
Deal found 11/11£418
Sun 8/206:00LTN - SEA
1 stop19h 00mMultiple Airlines
Deal found 12/11£418
Tue 9/1213:40LHR - SEA
2 stops29h 00mMultiple Airlines
Deal found 11/11£419
Sun 8/214:55LHR - SEA
Nonstop10h 00mAmerican Airlines
Deal found 12/11£420
Tue 9/1221:20STN - SEA
3 stops31h 15mMultiple Airlines
Deal found 11/11£421
Tue 9/1209:00LHR - SEA
2 stops20h 00mSWISS
Deal found 12/11£421
Tue 9/1213:00LGW - SEA
1 stop17h 26mMultiple Airlines
Deal found 11/11£422
Wed 19/1109:50LHR - SEA
1 stop16h 30mAer Lingus
Deal found 12/11£422
Tue 9/1220:45LHR - SEA
1 stop29h 35mAer Lingus
Deal found 11/11£423
Cheap flight deals from London to Seattle
Discover tips and strategies to find the most affordable flight options for your journey from London (LON) 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 14 November 2025.
Customise 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, Cheapflights users made 858,174 searches. Data last updated 14 November 2025.
Use the filters below to find and compare flights from London to Seattle that are best for you.
Fly from
London
Fly to
Seattle
Route
Depart
Return
Price
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Tue 16/12
20:35-17:00
1 stop28h 25m
Seattle/Tacoma Intl
Thu 15/1
14:35-10:50
1 stop12h 15m
£482
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Tue 16/12
20:35-17:00
1 stop28h 25m
Seattle/Tacoma Intl
Wed 14/1
14:35-19:30
1 stop20h 55m
£483
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Fri 13/2
14:55-16:55
Nonstop10h 00m
Seattle/Tacoma Intl
Thu 19/2
13:39-11:35
1 stop13h 56m
£495
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Wed 21/1
12:20-14:53
Nonstop10h 33m
Seattle/Tacoma Intl
Sat 24/1
22:59-06:25
1 stop23h 26m
£499
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Thu 27/11
12:15-17:00
1 stop12h 45m
Seattle/Tacoma Intl
Mon 1/12
14:35-10:50
1 stop12h 15m
£504
LondonSeattle
LGW - SEA
LGWSEA
London Gatwick
Tue 13/1
13:00-10:26
1 stop29h 26m
Seattle/Tacoma Intl
Thu 29/1
23:10-10:00
1 stop26h 50m
£511
LondonSeattle
LCY - SEA
LCYSEA
London City
Mon 2/2
08:40-20:46
2 stops20h 06m
Seattle/Tacoma Intl
Tue 10/2
07:10-08:10
2 stops17h 00m
£518
LondonSeattle
LCY - SEA
LCYSEA
London City
Thu 15/1
20:05-11:50
1 stop23h 45m
Seattle/Tacoma Intl
Thu 22/1
15:10-16:35
1 stop17h 25m
£519
LondonSeattle
LGW - SEA
LGWSEA
London Gatwick
Tue 5/5
13:00-17:50
1 stop12h 50m
Seattle/Tacoma Intl
Sat 9/5
19:00-14:40
1 stop11h 40m
£524
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Mon 2/2
06:30-12:10
1 stop13h 40m
Seattle/Tacoma Intl
Tue 10/2
10:58-11:15
1 stop16h 17m
£526
Flights are sorted by cheapest return flights first.
Deals found on 11/11
Showing 1-10 of 60 results
1
2
3
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6
Best time to book a flight from London to Seattle
Have a flexible travel schedule? Discover the best time to fly to Seattle from London 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 to Seattle
How far ahead should I book a flight from London to Seattle?
Use this chart to determine the optimal time to book a return flight from London to Seattle. Price data was last updated on 7 November 2025.
Booking 90 days in advance of your planned departure date is, on average, the best time to get cheap flights from London to Seattle. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
What is the cheapest month to book a flight from London to Seattle?
Currently, March is the cheapest month in which you can book a flight from London to Seattle (average of £310). Flying from London to Seattle in December is currently the most expensive (average of £473). 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 LON to SEA?
Find hourly flight availability from London 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 14 November 2025.
Unlike in the evening, when flights are generally more expensive, you can save up to 21% on flights from London to Seattle by exploring options for tickets in the morning.
What is the cheapest day to fly from London to Seattle?
Use this chart to determine the cheapest time to fly return from London to Seattle. Price data was last updated on 16 December 2024.
Travellers seeking maximum savings on their London to Seattle flight should consider departing on Wednesday mornings 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 to Seattle
Explore weekly flight availability from London 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 14 November 2025.
The most flights from LON to SEA are scheduled on a Friday (17 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (6 on average).
How much does it cost for a return flight from London to Seattle?
What’s the top stopover airport for flights from London to Seattle?
Share of one-stop return flights from London to Seattle chosen by Cheapflights users in the past 12 months, using the same stopover each way.
Reykjavik (KEF) – chosen by Cheapflights users on 77% of one-stop itineraries from London to Seattle on Cheapflights.
What’s the cheapest stopover airport for flights from London to Seattle?
Average return fare for one-stop flights from London to Seattle, chosen by Cheapflights users in the past 12 months, with the same stopover each way.
Calgary (YYC) is the most affordable one-stop option, with an average return flight price of £398.
What’s the fastest stopover option from London to Seattle?
Shortest average travel time for one-stop one-way flights from London to Seattle, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by stopover airport.
Flights via Paris (CDG) have the shortest average one-way travel time for one-stop routes: 13h 00m.
Which airport typically offers the quickest stopover for flights from London to Seattle?
Average stopover duration for one-stop one-way flights from London to Seattle, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.
Flights via Salt Lake City (SLC) offer the fastest connection on this route, with an average stopover time of 0h 52m.
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 14 November 2025.
Read reviews from past customers who have flown with KLM, Virgin Atlantic, andAir France
from London to Seattle. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
Related info for your journey
Find useful and relevant information for your journey from London 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?
Located just 11.4 mi from the city center, Seattle/Tacoma Intl is the airport most travelers will use when flying to Seattle from London. Booking flights from London to Seattle/Tacoma Intl (SEA) should be relatively easy as there are 13 daily inbound flights from London from 14 different airlines.
How long is the flight from London to Seattle?
A quick flight from London to Seattle can take about 10h. Icelandair provides one of the quickest options available for as low as £495. There are 4783 mi between London and Seattle. This flight may include one or multiple stops.
What are the cheapest airlines flying from London to Seattle round-trip?
Icelandair, at £350, was found to be the cheapest airline from London to Seattle.Alternate airlines flying return to your destination include Air France and Finnair. Icelandair is priced at 37% lower than the current average price of a flight leaving 3 months from now.
What are the cheapest airlines to fly from London to Seattle one-way?
£425 is the cheapest one-way deal found within the past few days, from Lufthansa. You may also be able to find cheap deals on British Airways and Icelandair, with prices starting from £430 and £442, respectively.
What are the most popular routes from London to Seattle?
When deciding which route to take from London to Seattle consider London Heathrow - Seattle/Tacoma Intl, London Gatwick - Seattle/Tacoma Intl or London City - Seattle/Tacoma Intl as they are the most popular.
What are the most reliable airlines from London to Seattle?
Consider Scandinavian Airlines (97%), Air France (89%) or KLM (88%) when booking your flight. These represent the most reliable airlines when flying from London to Seattle.
What are the cheapest flights from London to Seattle?
On average you can expect to pay £1,555 for a flight from London to Seattle. The cheapest flight overall is £422 while the most popular route, (London Heathrow - Seattle/Tacoma Intl) is currently priced at £366.
Can I find deals for business class flights from London to Seattle?
Yes. Cheapflights offers flight deals from London 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 to Seattle?
Currently, March is the cheapest month in which you can book a flight from London to Seattle (average of £310). Flying from London to Seattle in December is currently the most expensive (average of £473). 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.
Book flights to Seattle if you plan to visit one of these locations
Tacoma
Leavenworth
Bothell
SeaTac
Browse thousands of different options on Cheapflights for your next trip
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Fly from London to Seattle on these airlines
Choose from the following airlines for your flight from London to Seattle. Flights are based on user searches made on Cheapflights and were last updated on 14 November 2025.
Explore flights to Seattle departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on 14 November 2025.
Discover the top 10 airlines that operate flights from London 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 14 November 2025.
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 London to Seattle?
Cheapflights makes it easy to find London to Seattle flights by helping our users search from 900+ travel sites for deals. We also provide you with filters for cabin, price, airline, airports, number of stops, and many more to narrow down that perfect flight.
Why should you use Cheapflights to find cheap flight tickets from London to Seattle?
Millions of users choose and trust Cheapflights to book the best flight deals from London to Seattle for free. We help you search and compare prices from hundreds of airlines for the right flight just for you.
Can Cheapflights find flights from London to Seattle with no change fees?
Certainly. Search results for flights to Seattle from London shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.
Can Cheapflights notify me if prices for flights from London to Seattle become cheaper?
Yes, Cheapflights offers price alerts on London to Seattle flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.
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Cheapflights and its partners wish to use cookies or similar technologies to store and/or access information on and about your device and process personal data such as your IP address, device identifiers etc., in order to improve your experience on the site, to analyse navigation, to offer and measure personalised advertising, and to facilitate sharing on social networks. We also allow the use of third-party cookies (including those from our advertising partners) on our sites.
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