Cheap flights from Seattle to London Heathrow Airport from £207
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 10/10. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — LHR
11 Sep — 18 Sep1
Return
1 adult
Economy
Return
1 adult, Economy, 0 bags
Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London Heathrow are usually found in January or February, booked 35 days in advance, depart on a Tuesday or Wednesday and return on a Thursday
Cheap flight deals from Seattle to Heathrow
Enter your travel dates to find the best prices.
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Best
Direct
Last-minute
One-way
Cheapest flights from Seattle to Heathrow
Explore the most affordable flight options available from Seattle to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 12 August 2026.
Sat 3/1023:08 -
2 stops32h 52m
Tue 6/1006:40 -
2 stops15h 05m
Deal found 10/8£477
Tue 24/1108:31 -
2 stops15h 34m
Mon 30/1112:15 -
1 stop13h 40m
Deal found 10/8£479
Sat 26/915:55 -
2 stops17h 05m
Mon 28/910:20 -
1 stop35h 25m
Deal found 12/8£480
Mon 21/908:00 -
3 stops29h 20m
Mon 5/1021:05 -
2 stops27h 54m
Deal found 11/8£483
Tue 27/1015:35 -
2 stops22h 45m
Tue 3/1106:40 -
2 stops18h 20m
Deal found 8/8£485
Sat 19/915:55 -
2 stops17h 05m
Mon 21/906:40 -
2 stops24h 34m
Deal found 7/8£487
Tue 10/1108:19 -
2 stops15h 46m
Sat 21/1112:15 -
1 stop12h 45m
Deal found 12/8£489
Tue 6/1008:00 -
2 stops16h 05m
Tue 20/1013:05 -
1 stop15h 35m
Deal found 9/8£490
Tue 6/1008:00 -
2 stops16h 05m
Mon 19/1021:25 -
1 stop28h 30m
Deal found 11/8£491
Mon 9/1108:18 -
2 stops15h 47m
Thu 12/1112:15 -
1 stop12h 45m
Deal found 8/8£492
Best flights from Seattle to Heathrow
Discover carefully curated flight deals from Seattle to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 12 August 2026.
Tue 22/915:55 -
1 stop16h 05m
Thu 1/1006:40 -
2 stops39h 05m
Deal found 11/8£544
Sun 13/921:50 -
Nonstop9h 45m
Wed 23/906:30 -
1 stop18h 05m
Deal found 10/8£667
Sun 13/921:40 -
Nonstop9h 25m
Wed 23/917:00 -
Nonstop10h 00m
Deal found 9/8£689
Tue 22/917:30 -
Nonstop9h 50m
Tue 13/1011:40 -
Nonstop10h 20m
Deal found 9/8£689
Sun 13/915:55 -
2 stops16h 30m
Wed 23/907:05 -
2 stops24h 15m
Deal found 10/8£575
Wed 16/910:55 -
2 stops22h 45m
Fri 25/921:05 -
2 stops24h 40m
Deal found 7/8£608
Sat 17/1022:59 -
1 stop13h 11m
Wed 28/1012:20 -
Nonstop10h 34m
Deal found 11/8£692
Sat 19/921:50 -
Nonstop9h 45m
Thu 1/1006:30 -
1 stop13h 22m
Deal found 8/8£704
Fri 15/118:55 -
Nonstop9h 25m
Mon 25/114:45 -
Nonstop10h 05m
Deal found 10/8£713
Wed 9/921:50 -
Nonstop9h 45m
Sat 19/911:45 -
1 stop12h 50m
Deal found 8/8£704
Thu 17/921:50 -
Nonstop9h 45m
Mon 28/917:35 -
1 stop25h 40m
Deal found 7/8£719
Thu 1/1021:40 -
Nonstop9h 25m
Thu 29/1014:45 -
Nonstop10h 20m
Deal found 9/8£726
Direct flights from Seattle to Heathrow
Explore direct flight options from Seattle to Heathrow based on user searches, and compare prices and availability for your desired travel dates. Data last updated 12 August 2026.
Mon 30/1118:45 -
Nonstop9h 25m
Tue 8/1214:55 -
Nonstop9h 55m
Deal found 7/8£615
Mon 16/1118:45 -
Nonstop9h 25m
Mon 23/1114:55 -
Nonstop9h 55m
Deal found 11/8£616
Wed 13/118:55 -
Nonstop9h 25m
Sat 23/114:55 -
Nonstop9h 55m
Deal found 10/8£622
Mon 9/1118:55 -
Nonstop9h 25m
Sat 6/214:55 -
Nonstop9h 55m
Deal found 11/8£623
Tue 1/1213:30 -
Nonstop9h 30m
Tue 12/114:55 -
Nonstop9h 55m
Deal found 12/8£623
Wed 25/1118:45 -
Nonstop9h 25m
Sun 13/1214:45 -
Nonstop10h 05m
Deal found 10/8£627
Mon 7/1218:45 -
Nonstop9h 25m
Mon 14/1214:45 -
Nonstop10h 05m
Deal found 11/8£628
Mon 30/1118:45 -
Nonstop9h 25m
Sat 12/1214:45 -
Nonstop10h 05m
Deal found 7/8£629
Tue 22/913:30 -
Nonstop9h 15m
Tue 29/909:50 -
Nonstop9h 45m
Deal found 9/8£629
Mon 28/920:20 -
Nonstop9h 25m
Tue 20/1009:50 -
Nonstop9h 45m
Deal found 9/8£632
Mon 9/1118:45 -
Nonstop9h 25m
Wed 18/1114:55 -
Nonstop9h 55m
Deal found 8/8£633
Mon 21/913:30 -
Nonstop9h 15m
Mon 5/1009:50 -
Nonstop9h 45m
Deal found 11/8£635
Last-minute flights from Seattle to Heathrow
Discover last-minute flight deals from Seattle to Heathrow. Data last updated 12 August 2026 and is based on user searches.
Thu 10/908:00 -
2 stops29h 20m
Tue 15/921:05 -
3 stops29h 27m
Deal found 9/8£493
Fri 18/915:55 -
2 stops37h 00m
Mon 21/910:20 -
2 stops21h 00m
Deal found 7/8£503
Sat 19/915:55 -
2 stops17h 05m
Mon 21/906:40 -
2 stops24h 34m
Deal found 7/8£487
Mon 21/908:00 -
3 stops29h 20m
Mon 5/1021:05 -
2 stops27h 54m
Deal found 11/8£483
Tue 22/915:55 -
1 stop16h 05m
Tue 29/906:40 -
1 stop15h 05m
Deal found 9/8£504
Sat 26/915:55 -
2 stops17h 05m
Mon 28/910:20 -
1 stop35h 25m
Deal found 12/8£480
Sun 27/915:40 -
2 stops21h 40m
Tue 6/1006:40 -
2 stops22h 00m
Deal found 8/8£496
One-way flights from Seattle to Heathrow
Search for one-way flight options from Seattle to Heathrow. Find affordable one-way fares based on user searches. Data last updated 12 August 2026.
Sat 10/1015:40 -
1 stop12h 15m
Deal found 11/8£207
Mon 5/1015:40 -
1 stop12h 15m
Deal found 11/8£208
Sun 4/1019:00 -
1 stop32h 55m
Deal found 10/8£210
Thu 15/1019:00 -
1 stop17h 20m
Deal found 10/8£211
Sun 11/1019:00 -
1 stop17h 20m
Deal found 12/8£212
Sun 6/915:40 -
1 stop12h 15m
Deal found 7/8£213
Mon 14/919:00 -
1 stop32h 55m
Deal found 10/8£214
Tue 3/1114:35 -
1 stop20h 55m
Deal found 12/8£215
Tue 8/923:25 -
1 stop12h 55m
Deal found 11/8£215
Sat 5/923:25 -
1 stop28h 30m
Deal found 10/8£217
Find flight deals from Seattle to Heathrow
Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Heathrow (LHR). 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 12 August 2026.
Customise your flight search to find flights from Seattle to Heathrow 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 12 August 2026.
Use the filters below to find and compare flights from Seattle to London Heathrow Airport that are best for you.
Fly from
Fly to
Route
Depart
Return
Price
Cheapest return flight
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Tue 22/9
15:55-16:00
1 stop16h 05m
London Heathrow
Thu 1/10
06:40-13:45
2 stops39h 05m
£544
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Sun 13/9
15:55-16:25
2 stops16h 30m
London Heathrow
Wed 23/9
07:05-23:20
2 stops24h 15m
£575
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Wed 16/9
10:55-17:40
2 stops22h 45m
London Heathrow
Fri 25/9
21:05-13:45
2 stops24h 40m
£608
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Sun 13/9
21:50-15:35
Nonstop9h 45m
London Heathrow
Wed 23/9
06:30-16:35
1 stop18h 05m
£667
Fastest return journey
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Sun 13/9
21:40-15:05
Nonstop9h 25m
London Heathrow
Wed 23/9
17:00-19:00
Nonstop10h 00m
£689
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Tue 22/9
17:30-11:20
Nonstop9h 50m
London Heathrow
Tue 13/10
11:40-14:00
Nonstop10h 20m
£689
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Sat 17/10
22:59-20:10
1 stop13h 11m
London Heathrow
Wed 28/10
12:20-15:54
Nonstop10h 34m
£692
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Sat 19/9
21:50-15:35
Nonstop9h 45m
London Heathrow
Thu 1/10
06:30-11:52
1 stop13h 22m
£704
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Wed 9/9
21:50-15:35
Nonstop9h 45m
London Heathrow
Sat 19/9
11:45-16:35
1 stop12h 50m
£704
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Fri 15/1
18:55-12:20
Nonstop9h 25m
London Heathrow
Mon 25/1
14:45-16:50
Nonstop10h 05m
£713
Flights are sorted by cheapest return flights first.
Deals found on 10/8
Showing 1-10 of 22 resultsSorted by cheapest first
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2
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Best time to book a flight from Seattle to Heathrow
Have a flexible travel schedule? Discover the best time to fly to Heathrow from Seattle with our price prediction graph.
SEA-LHR
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 Seattle to London Heathrow Airport
Prices
Airlines
Delays
More
How far ahead should I book a flight from Seattle to London Heathrow Airport?
The price you pay for your flight from Seattle to London Heathrow Airport may vary depending on when you book. For the best chance of a lower fare, look to book 34 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest month to book a flight from Seattle to London Heathrow Airport?
Currently, January is the cheapest month in which you can book a flight from Seattle to London Heathrow Airport (average of £475). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of £923). 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 SEA to LHR?
Find hourly flight availability from Seattle to Heathrow. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 12 August 2026.
When flying from Seattle to London Heathrow Airport, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
How much does it cost for a return flight from Seattle to London Heathrow Airport?
Airfare is below average for this route at the moment.
Seattle to London Heathrow Airport flights typically cost between £509 and £718 in October.The cheapest return price found within the last 5 days was £477 on Scandinavian Airlines (3 Oct–6 Oct).
Weekly flight availability from Seattle to London Heathrow Airport
Explore weekly flight availability from Seattle to Heathrow. 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 12 August 2026.
The most flights from SEA to LHR are scheduled on a Monday (24 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (19 on average).
How often are flights from Seattle to London delayed?
About 14% of weekly flights between Seattle and London have experienced delays in the past year, with the average delay time being 133 minutes.
What is the most punctual flight time for Seattle to London flights?
Historically, flights departing in the early afternoon are less likely to be delayed, whereas flights leaving in the evening tend to experience delays more often.
What day of the week experiences the fewest flight delays on this route?
Saturday 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 Seattle to London flights?
Over the past year, Virgin Atlantic 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 Seattle to London Heathrow Airport?
Share of one-stop return flights from Seattle to London Heathrow Airport chosen by Cheapflights users in the past 12 months, using the same stopover each way.
Dublin (DUB) – chosen by Cheapflights users on 67% of one-stop itineraries from Seattle to London Heathrow Airport on Cheapflights.
What’s the cheapest stopover airport for flights from Seattle to London Heathrow Airport?
Average return fare for one-stop flights from Seattle to London Heathrow Airport, chosen by Cheapflights users in the past 12 months, with the same stopover each way.
Reykjavik (KEF) is the most affordable one-stop option, with an average return flight price of £370.
What’s the fastest stopover option from Seattle to London Heathrow Airport?
Shortest average travel time for one-stop one-way flights from Seattle to London Heathrow Airport, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by stopover airport.
Flights via Reykjavik (KEF) have the shortest average one-way travel time for one-stop routes: 12h 15m.
Which airport typically offers the quickest stopover for flights from Seattle to London Heathrow Airport?
Average stopover duration for one-stop one-way flights from Seattle to London Heathrow Airport, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.
Flights via Reykjavik (KEF) offer the fastest connection on this route, with an average stopover time of 1h 25m.
Reviews of airlines servicing Heathrow
Get insights into the airlines that provide service to Heathrow. 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 Heathrow. Reviews last updated 12 August 2026.
Read through reviews of airlines operating flights from Seattle to London Heathrow Airport, such as Alaska Airlines,Virgin Atlantic, andBritish Airways. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle
Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle
Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle
Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle
Related info for your journey
Find useful and relevant information for your journey from Seattle to Heathrow. 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 from for flights from Seattle to London Heathrow?
If you book a flight to London Heathrow from Seattle, you will be flying from 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 21 flights from Seattle/Tacoma Intl to London Heathrow per day from 3 different airlines.
How long is the flight from Seattle to London Heathrow Airport?
For as low as £689, Scandinavian Airlines can have you in London Heathrow Airport from Seattle in 9h 25m. The distance from Seattle to London Heathrow Airport is about 4783 mi. This flight may include one or multiple stops.
What are the cheapest airlines flying from Seattle to London Heathrow Airport round-trip?
Cheapflights users have booked flights from Seattle to London Heathrow Airport round-trip from £458. Other airlines that can offer you cheap pricing are Alaska Airlines, from £488, and Virgin Atlantic, from £495. You may be able to fly from Seattle to London Heathrow Airport for 27% less than the average price by searching for these airlines.
What are the cheapest airlines to fly from Seattle to London Heathrow Airport one-way?
One-way options have recently been found by users for as low as £126 on Icelandair. Other airlines that offer cheap prices include Virgin Atlantic from £216 and British Airways from £241 one-way.
What are the most reliable airlines from Seattle to London Heathrow Airport?
Consider SAUDIA (100%), KLM (84%) or Air France (84%) when booking your flight. These represent the most reliable airlines when flying from Seattle to London Heathrow Airport.
What are the cheapest flights from Seattle to London Heathrow Airport?
While on average a flight from Seattle to London Heathrow Airport is generally £526, our data shows the cheapest flight currently is £240. When looking at the most popular route, (Seattle/Tacoma Intl - London Heathrow), you can expect to pay £413 for that flight.
Can I find deals for business class flights from Seattle to Heathrow?
Yes. Cheapflights offers flight deals from Seattle to Heathrow 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 Seattle to London Heathrow Airport?
Currently, January is the cheapest month in which you can book a flight from Seattle to London Heathrow Airport (average of £475). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of £923). 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.
Explore flights to Heathrow departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on 12 August 2026.
Discover the top 3 airlines that operate flights from Seattle to Heathrow. 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 12 August 2026.
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 Seattle to Heathrow?
Cheapflights helps you search for flights from Seattle to Heathrow via 900+ travel sites so you don’t have to. After performing a flight search, users can also filter their flight selection by filtering for price, number of stops, airlines, and so on.
Why should you use Cheapflights to find cheap flight tickets from Seattle to Heathrow?
Cheapflights helps you find that perfect flight to Heathrow from Seattle 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 Seattle to Heathrow with no change fees?
Yes! Cheapflights helps users easily find flights from Seattle to Heathrow with no change fees.
Can Cheapflights notify me if prices for flights from Seattle to Heathrow become cheaper?
Yes, and it’s super simple to set up. Click the bell icon next to the flight deals above and provide a valid email address to enable Price Alerts. That’s it!
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