Cheap flights from London Heathrow Airport to Seattle from £377
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 3/3. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — SEA
27 Jan — 3 Feb1
Return
1 adult
Economy
Return
1 adult, Economy, 0 bags
Cheapflights Tip: The best prices from London Heathrow to Seattle/Tacoma Intl are usually found in February or September, booked 62 days in advance, depart on a Wednesday or Tuesday and return on a Tuesday
Cheap flight deals from Heathrow to Seattle
Enter your travel dates to find the best prices.
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 28 December 2025.
Tue 30/1215:00LHR - SEA
1 stop16h 08mBritish Airways
Tue 13/108:35SEA - LHR
1 stop19h 40mBritish Airways
Deal found 26/12£717
Tue 30/1215:00LHR - SEA
1 stop17h 57mBritish Airways
Wed 7/111:55SEA - LHR
1 stop36h 40mBritish Airways
Deal found 26/12£717
Tue 30/1215:00LHR - SEA
1 stop17h 57mBritish Airways
Sun 4/107:07SEA - LHR
1 stop18h 53mBritish Airways
Deal found 26/12£729
Mon 29/1214:55LHR - SEA
Nonstop10h 00mAmerican Airlines
Tue 13/111:55SEA - LHR
1 stop14h 05mAmerican Airlines
Deal found 26/12£739
Mon 29/1214:55LHR - SEA
Nonstop10h 00mAmerican Airlines
Fri 16/112:45SEA - LHR
1 stop15h 15mAmerican Airlines
Deal found 26/12£740
Tue 30/1210:15LHR - SEA
1 stop19h 49mBritish Airways
Thu 8/114:10SEA - LHR
2 stops58h 15mBritish Airways
Deal found 26/12£745
Mon 29/1213:25LHR - SEA
2 stops28h 06mAir Canada
Fri 16/115:40SEA - LHR
1 stop12h 10mAir Canada
Deal found 26/12£769
Mon 29/1214:55LHR - SEA
Nonstop10h 00mBritish Airways
Sat 17/118:50SEA - LHR
Nonstop9h 30mBritish Airways
Deal found 26/12£774
Mon 29/1211:55LHR - SEA
1 stop17h 16mBritish Airways
Sun 18/111:55SEA - LHR
1 stop15h 45mBritish Airways
Deal found 26/12£777
Fri 26/1209:25LHR - SEA
Nonstop10h 05mAmerican Airlines
Wed 31/1211:20SEA - LHR
1 stop12h 55mAmerican Airlines
Deal found 26/12£780
Best flights from Heathrow to Seattle
Discover carefully curated flight deals from Heathrow to Seattle that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 28 December 2025.
Thu 22/114:30LHR - SEA
1 stop26h 45mUnited Airlines
Mon 26/108:40SEA - LHR
2 stops16h 30mUnited Airlines
Deal found 24/12£410
Mon 12/106:00LHR - SEA
2 stops24h 43mSWISS
Mon 26/112:35SEA - LHR
2 stops21h 15mSWISS
Deal found 24/12£412
Fri 6/206:30LHR - SEA
1 stop13h 10mKLM
Tue 24/317:40SEA - LHR
Nonstop9h 50mKLM
Deal found 27/12£415
Sat 17/106:30LHR - SEA
1 stop13h 20mVirgin Atlantic
Thu 22/116:45SEA - LHR
Nonstop9h 45mVirgin Atlantic
Deal found 27/12£415
Fri 13/206:30LHR - SEA
1 stop13h 10mDelta
Thu 19/218:25SEA - LHR
Nonstop9h 30mDelta
Deal found 25/12£415
Sun 18/120:35LHR - SEA
1 stop28h 25mIcelandair
Thu 22/114:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 27/12£421
Fri 6/206:30LHR - SEA
1 stop13h 10mKLM
Thu 12/216:55SEA - LHR
Nonstop9h 35mKLM
Deal found 25/12£415
Thu 15/106:20LHR - SEA
1 stop13h 05mVirgin Atlantic
Tue 20/116:45SEA - LHR
Nonstop9h 45mVirgin Atlantic
Deal found 25/12£419
Mon 19/112:20LHR - SEA
Nonstop10h 29mDelta
Sun 25/116:45SEA - LHR
Nonstop9h 45mDelta
Deal found 25/12£427
Sat 24/115:05LHR - SEA
Nonstop10h 05mDelta
Tue 27/116:45SEA - LHR
Nonstop9h 45mDelta
Deal found 25/12£427
Direct flights from Heathrow to Seattle
Explore direct flight options from Heathrow to Seattle based on user searches, and compare prices and availability for your desired travel dates. Data last updated 28 December 2025.
Thu 16/417:40LHR - SEA
Nonstop10h 19mVirgin Atlantic
Tue 28/418:20SEA - LHR
Nonstop9h 50mVirgin Atlantic
Deal found 27/12£411
Mon 13/411:40LHR - SEA
Nonstop10h 20mVirgin Atlantic
Sun 26/418:20SEA - LHR
Nonstop9h 50mVirgin Atlantic
Deal found 26/12£412
Wed 8/416:30LHR - SEA
Nonstop9h 55mAmerican Airlines
Wed 15/420:20SEA - LHR
Nonstop9h 25mAmerican Airlines
Deal found 27/12£414
Wed 14/112:20LHR - SEA
Nonstop10h 29mVirgin Atlantic
Sun 1/216:55SEA - LHR
Nonstop9h 35mVirgin Atlantic
Deal found 27/12£419
Mon 4/511:40LHR - SEA
Nonstop10h 20mVirgin Atlantic
Fri 15/518:20SEA - LHR
Nonstop9h 50mVirgin Atlantic
Deal found 27/12£421
Thu 22/112:20LHR - SEA
Nonstop10h 29mKLM
Mon 26/116:45SEA - LHR
Nonstop9h 45mKLM
Deal found 25/12£427
Mon 12/112:20LHR - SEA
Nonstop10h 29mDelta
Sun 1/216:55SEA - LHR
Nonstop9h 35mDelta
Deal found 27/12£428
Tue 19/509:50LHR - SEA
Nonstop9h 45mBritish Airways
Fri 5/613:35SEA - LHR
Nonstop9h 15mBritish Airways
Deal found 27/12£429
Sun 25/112:20LHR - SEA
Nonstop10h 29mVirgin Atlantic
Sun 1/216:55SEA - LHR
Nonstop9h 35mVirgin Atlantic
Deal found 26/12£429
Tue 23/609:50LHR - SEA
Nonstop9h 45mAmerican Airlines
Mon 13/720:20SEA - LHR
Nonstop9h 25mAmerican Airlines
Deal found 27/12£431
Sat 24/115:05LHR - SEA
Nonstop10h 05mVirgin Atlantic
Sat 31/118:25SEA - LHR
Nonstop9h 30mVirgin Atlantic
Deal found 27/12£435
Fri 27/212:20LHR - SEA
Nonstop10h 25mVirgin Atlantic
Sat 14/319:25SEA - LHR
Nonstop9h 30mVirgin Atlantic
Deal found 26/12£435
Last-minute flights from Heathrow to Seattle
Discover last-minute flight deals from Heathrow to Seattle. Data last updated 28 December 2025 and is based on user searches.
Mon 12/106:00LHR - SEA
2 stops24h 43mSWISS
Mon 26/112:35SEA - LHR
2 stops21h 15mSWISS
Deal found 24/12£412
Mon 12/112:20LHR - SEA
Nonstop10h 29mDelta
Sun 1/216:55SEA - LHR
Nonstop9h 35mDelta
Deal found 27/12£428
Wed 14/112:20LHR - SEA
Nonstop10h 29mVirgin Atlantic
Sun 1/216:55SEA - LHR
Nonstop9h 35mVirgin Atlantic
Deal found 27/12£419
Sun 18/120:35LHR - SEA
1 stop28h 25mIcelandair
Thu 22/114:35SEA - LHR
1 stop12h 15mIcelandair
Deal found 27/12£421
Thu 22/106:30LHR - SEA
1 stop13h 20mKLM
Mon 26/116:45SEA - LHR
Nonstop9h 45mKLM
Deal found 25/12£415
Thu 22/113:00LHR - SEA
2 stops28h 15mAir Canada
Mon 26/105:50SEA - LHR
2 stops20h 20mAir Canada
Deal found 24/12£415
Sat 24/114:30LHR - SEA
1 stop15h 36mAir Canada
Tue 27/115:40SEA - LHR
1 stop12h 10mAir Canada
Deal found 25/12£410
Sun 25/112:20LHR - SEA
Nonstop10h 29mVirgin Atlantic
Sun 1/216:55SEA - LHR
Nonstop9h 35mVirgin Atlantic
Deal found 26/12£429
Mon 26/118:00LHR - SEA
2 stops33h 16mAir Canada
Fri 6/205:50SEA - LHR
2 stops17h 20mAir Canada
Deal found 25/12£417
Wed 28/111:10LHR - SEA
2 stops18h 56mMultiple Airlines
Wed 11/205:00SEA - LHR
2 stops17h 30mMultiple Airlines
Deal found 25/12£421
Fri 30/112:00LHR - SEA
2 stops29h 15mAir Canada
Tue 10/215:40SEA - LHR
1 stop12h 10mAir Canada
Deal found 25/12£411
One-way flights from Heathrow to Seattle
Search for one-way flight options from Heathrow to Seattle. Find affordable one-way fares based on user searches. Data last updated 28 December 2025.
Tue 24/209:25LHR - SEA
Nonstop10h 05mAmerican Airlines
Deal found 27/12£377
Mon 6/414:10LHR - SEA
2 stops29h 22mMultiple Airlines
Deal found 27/12£378
Fri 15/512:00LHR - SEA
1 stop12h 59mAer Lingus
Deal found 26/12£379
Sat 28/214:50LHR - SEA
1 stop31h 29mWestJet
Deal found 27/12£381
Wed 25/306:00LHR - SEA
2 stops23h 45mSWISS
Deal found 27/12£382
Sun 22/309:55LHR - SEA
3 stops44h 21mMultiple Airlines
Deal found 26/12£383
Sun 8/320:15LHR - SEA
2 stops23h 55mLufthansa
Deal found 27/12£384
Wed 25/214:55LHR - SEA
Nonstop10h 00mFinnair
Deal found 26/12£384
Wed 7/115:15LHR - SEA
3 stops51h 07mMultiple Airlines
Deal found 27/12£386
Fri 23/119:40LHR - SEA
3 stops31h 25mMultiple Airlines
Deal found 26/12£386
Sat 24/120:50LHR - SEA
3 stops32h 06mMultiple Airlines
Deal found 27/12£387
Wed 11/207:40LHR - SEA
3 stops21h 32mUnited Airlines
Deal found 26/12£388
Find 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 28 December 2025.
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 28 December 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
Thu 22/1
14:30-09:15
1 stop26h 45m
Seattle/Tacoma Intl
Mon 26/1
08:40-09:10
2 stops16h 30m
£410
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Mon 12/1
06:00-22:43
2 stops24h 43m
Seattle/Tacoma Intl
Mon 26/1
12:35-17:50
2 stops21h 15m
£412
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Fri 6/2
06:30-11:40
1 stop13h 10m
Seattle/Tacoma Intl
Tue 24/3
17:40-10:30
Nonstop9h 50m
£415
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Sat 17/1
06:30-11:50
1 stop13h 20m
Seattle/Tacoma Intl
Thu 22/1
16:45-10:30
Nonstop9h 45m
£415
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Fri 13/2
06:30-11:40
1 stop13h 10m
Seattle/Tacoma Intl
Thu 19/2
18:25-11:55
Nonstop9h 30m
£415
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Fri 6/2
06:30-11:40
1 stop13h 10m
Seattle/Tacoma Intl
Thu 12/2
16:55-10:30
Nonstop9h 35m
£415
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Thu 15/1
06:20-11:25
1 stop13h 05m
Seattle/Tacoma Intl
Tue 20/1
16:45-10:30
Nonstop9h 45m
£419
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Sun 18/1
20:35-17:00
1 stop28h 25m
Seattle/Tacoma Intl
Thu 22/1
14:35-10:50
1 stop12h 15m
£421
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Mon 19/1
12:20-14:49
Nonstop10h 29m
Seattle/Tacoma Intl
Sun 25/1
16:45-10:30
Nonstop9h 45m
£427
LondonSeattle
LHR - SEA
LHRSEA
London Heathrow
Sat 24/1
15:05-17:10
Nonstop10h 05m
Seattle/Tacoma Intl
Tue 27/1
16:45-10:30
Nonstop9h 45m
£427
Flights are sorted by cheapest return flights first.
Deals found on 27/12
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
Prices
Airlines
Delays
More
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 26 December 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 £338). Flying from London Heathrow Airport to Seattle in July is currently the most expensive (average of £505). 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 28 December 2025.
It’s typically best to fly out from London Heathrow Airport to Seattle in the evening. Doing so could potentially save you 16% 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 20 December 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. Friday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.
How much does it cost for a return flight from London Heathrow Airport to Seattle?
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 28 December 2025.
The most flights from LHR to SEA are scheduled on a Saturday (21 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (6 on average).
How often are flights from London to Seattle delayed?
About 13% of weekly flights between London and Seattle have experienced delays in the past year, with the average delay time being 119 minutes.
What is the most punctual flight time for London to Seattle flights?
Historically, flights departing in the evening are less likely to be delayed, whereas flights leaving in the early afternoon tend to experience delays more often.
What day of the week experiences the fewest flight delays on this route?
Tuesday tends to have the lowest number of delays on this route, whereas Wednesday has historically faced a higher average of delays compared to other days of the week.
Which airline has the best punctuality record on London to Seattle flights?
Over the past year, Delta have had the lowest number of delays on this route, with just 6% of flights being delayed.
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 58% 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 £432.
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 Frankfurt am Main (FRA) have the shortest average one-way travel time for one-stop routes: 13h 40m.
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 28 December 2025.
See what other customers who have flown with KLM, Virgin Atlantic, andAir France 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.
Not literally sitting in the very last row in the middle
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 13 flights from London Heathrow to Seattle/Tacoma Intl per day from 14 different airlines.
How long is the flight from London Heathrow Airport to Seattle?
Departing from London Heathrow Airport to Seattle will take you 13h 10m. The distance from London Heathrow Airport to Seattle is about 4783 mi. This flight may include one or multiple stops.
What are the cheapest airlines flying from London Heathrow Airport to Seattle round-trip?
According to our current data, Icelandair (£352), Air France (£384), and Lufthansa (£393) offers the cheapest pricing from London Heathrow Airport to Seattle. 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 Heathrow Airport to Seattle one-way?
The cheapest airline one-way is WestJet, with whom users have recently found tickets for as low as £250. However, be on the lookout for offers from British Airways and Icelandair, as they are both options that can get you from London Heathrow Airport to Seattle for a low price.
What are the most reliable airlines from London Heathrow Airport to Seattle?
Consider Scandinavian Airlines (97%), Air France (93%) or Delta (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 £409. On average you can expect to pay £1,656. The most popular route, (London Heathrow - Seattle/Tacoma Intl), can usually be booked for £235.
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 £338). Flying from London Heathrow Airport to Seattle in July is currently the most expensive (average of £505). 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
SeaTac
Browse thousands of different options on Cheapflights for your next trip
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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 28 December 2025.
Browse through other flights departing from Heathrow. Flights are based on user searches made on Cheapflights and were last updated on 28 December 2025.
Explore flights to Seattle departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on 28 December 2025.
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 28 December 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 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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