Cheap flights from Seattle to London Heathrow Airport from £209
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
6 Sep — 13 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
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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 7 August 2026.
Fri 16/1015:40 -
1 stop12h 15m
Sat 14/1112:15 -
1 stop12h 45m
Deal found 4/8£465
Sun 11/1015:40 -
1 stop12h 15m
Sun 8/1112:15 -
1 stop12h 45m
Deal found 4/8£470
Mon 23/1108:31 -
2 stops15h 34m
Mon 7/1212:15 -
1 stop12h 45m
Deal found 5/8£470
Sat 19/915:55 -
1 stop21h 45m
Mon 21/921:05 -
2 stops24h 40m
Deal found 3/8£471
Sun 11/1015:40 -
1 stop12h 15m
Mon 9/1112:15 -
1 stop12h 45m
Deal found 4/8£472
Tue 24/1108:31 -
2 stops15h 34m
Tue 29/1212:15 -
1 stop12h 45m
Deal found 3/8£472
Fri 2/1007:15 -
2 stops24h 45m
Sun 4/1006:40 -
2 stops15h 05m
Deal found 1/8£475
Wed 19/808:00 -
2 stops25h 00m
Tue 25/806:40 -
2 stops22h 27m
Deal found 2/8£477
Tue 15/923:08 -
2 stops35h 22m
Fri 18/918:05 -
2 stops27h 40m
Deal found 2/8£478
Sun 27/915:55 -
2 stops33h 00m
Wed 30/906:40 -
2 stops24h 40m
Deal found 1/8£482
Mon 12/1015:40 -
1 stop12h 15m
Tue 10/1112:15 -
1 stop12h 45m
Deal found 4/8£484
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 7 August 2026.
Sun 13/915:55 -
2 stops20h 00m
Wed 23/907:05 -
2 stops24h 15m
Deal found 6/8£579
Mon 7/917:30 -
Nonstop9h 50m
Tue 22/911:40 -
Nonstop10h 20m
Deal found 1/8£690
Mon 21/921:40 -
Nonstop9h 25m
Tue 13/1017:00 -
Nonstop10h 00m
Deal found 1/8£701
Wed 21/1005:40 -
1 stop23h 40m
Sat 31/1006:50 -
2 stops21h 06m
Deal found 4/8£727
Thu 24/913:30 -
Nonstop9h 15m
Thu 15/1009:50 -
Nonstop9h 45m
Deal found 2/8£727
Fri 18/917:30 -
Nonstop9h 50m
Mon 21/911:40 -
Nonstop10h 20m
Deal found 6/8£765
Sat 16/118:55 -
Nonstop9h 25m
Sun 24/114:45 -
Nonstop10h 05m
Deal found 4/8£715
Thu 17/921:50 -
Nonstop9h 45m
Mon 28/917:35 -
1 stop25h 40m
Deal found 2/8£721
Thu 17/912:10 -
1 stop15h 25m
Sun 27/906:50 -
2 stops19h 29m
Deal found 4/8£755
Mon 17/821:45 -
Nonstop9h 50m
Tue 25/811:45 -
1 stop12h 42m
Deal found 3/8£743
Sun 31/112:00 -
1 stop14h 00m
Thu 4/214:55 -
Nonstop9h 55m
Deal found 4/8£828
Thu 3/920:10 -
Nonstop9h 50m
Sun 20/918:30 -
Nonstop10h 23m
Deal found 1/8£764
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 7 August 2026.
Sun 11/1020:20 -
Nonstop9h 25m
Tue 10/1109:25 -
Nonstop10h 00m
Deal found 4/8£538
Sat 17/1020:20 -
Nonstop9h 25m
Thu 12/1109:25 -
Nonstop10h 00m
Deal found 4/8£544
Sun 11/1020:20 -
Nonstop9h 25m
Sat 14/1109:25 -
Nonstop10h 00m
Deal found 4/8£547
Wed 14/1013:30 -
Nonstop9h 15m
Tue 10/1109:25 -
Nonstop10h 00m
Deal found 4/8£558
Tue 13/1020:20 -
Nonstop9h 25m
Fri 13/1114:55 -
Nonstop9h 55m
Deal found 4/8£559
Fri 16/1013:30 -
Nonstop9h 15m
Thu 12/1109:25 -
Nonstop10h 00m
Deal found 4/8£567
Wed 14/1013:30 -
Nonstop9h 15m
Sat 14/1109:25 -
Nonstop10h 00m
Deal found 4/8£569
Thu 15/1020:20 -
Nonstop9h 25m
Fri 13/1114:55 -
Nonstop9h 55m
Deal found 4/8£576
Sat 17/1020:20 -
Nonstop9h 25m
Mon 9/1114:55 -
Nonstop9h 55m
Deal found 4/8£587
Thu 15/1020:20 -
Nonstop9h 25m
Sun 8/1114:55 -
Nonstop9h 55m
Deal found 4/8£590
Fri 16/1013:30 -
Nonstop9h 15m
Wed 11/1114:55 -
Nonstop9h 55m
Deal found 4/8£597
Thu 15/1013:30 -
Nonstop9h 15m
Mon 9/1114:55 -
Nonstop9h 55m
Deal found 4/8£607
Last-minute flights from Seattle to Heathrow
Discover last-minute flight deals from Seattle to Heathrow. Data last updated 7 August 2026 and is based on user searches.
Tue 11/823:25 -
1 stop12h 55m
Tue 18/821:25 -
1 stop22h 20m
Deal found 2/8£617
Tue 11/810:40 -
3 stops27h 00m
Tue 25/806:40 -
2 stops22h 27m
Deal found 5/8£625
Tue 11/823:25 -
1 stop12h 55m
Sun 6/921:25 -
1 stop22h 20m
Deal found 1/8£633
Wed 12/810:40 -
3 stops27h 00m
Wed 19/818:40 -
2 stops30h 19m
Deal found 5/8£529
Sun 16/819:00 -
3 stops30h 35m
Wed 26/806:40 -
2 stops22h 00m
Deal found 2/8£556
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 7 August 2026.
Sat 10/1015:40 -
1 stop12h 15m
Deal found 4/8£209
Mon 5/1019:00 -
1 stop32h 55m
Deal found 2/8£209
Fri 16/1019:00 -
1 stop17h 20m
Deal found 2/8£210
Sun 4/1019:00 -
1 stop32h 55m
Deal found 4/8£211
Mon 18/114:35 -
1 stop12h 15m
Deal found 3/8£212
Wed 7/1019:00 -
1 stop17h 20m
Deal found 4/8£212
Sun 20/919:00 -
1 stop17h 20m
Deal found 2/8£213
Mon 14/919:00 -
1 stop32h 55m
Deal found 2/8£215
Fri 4/923:25 -
1 stop28h 30m
Deal found 5/8£215
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 7 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 7 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
Sun 13/9
15:55-19:55
2 stops20h 00m
London Heathrow
Wed 23/9
07:05-23:20
2 stops24h 15m
£579
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Mon 7/9
17:30-11:20
Nonstop9h 50m
London Heathrow
Tue 22/9
11:40-14:00
Nonstop10h 20m
£690
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Mon 21/9
21:40-15:05
Nonstop9h 25m
London Heathrow
Tue 13/10
17:00-19:00
Nonstop10h 00m
£701
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Sat 16/1
18:55-12:20
Nonstop9h 25m
London Heathrow
Sun 24/1
14:45-16:50
Nonstop10h 05m
£715
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Thu 17/9
21:50-15:35
Nonstop9h 45m
London Heathrow
Mon 28/9
17:35-11:15
1 stop25h 40m
£721
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Wed 21/10
05:40-13:20
1 stop23h 40m
London Heathrow
Sat 31/10
06:50-20:56
2 stops21h 06m
£727
Fastest return journey
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Thu 24/9
13:30-06:45
Nonstop9h 15m
London Heathrow
Thu 15/10
09:50-11:35
Nonstop9h 45m
£727
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Mon 17/8
21:45-15:35
Nonstop9h 50m
London Heathrow
Tue 25/8
11:45-16:27
1 stop12h 42m
£743
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Thu 17/9
12:10-11:35
1 stop15h 25m
London Heathrow
Sun 27/9
06:50-18:19
2 stops19h 29m
£755
SeattleLondon
SEA Seattle/Tacoma Intl - LHR London Heathrow
SEALHR
Seattle/Tacoma Intl
Thu 3/9
20:10-14:00
Nonstop9h 50m
London Heathrow
Sun 20/9
18:30-20:53
Nonstop10h 23m
£764
Flights are sorted by cheapest return flights first.
Deals found on 3/8
Showing 1-10 of 23 resultsSorted by cheapest first
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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
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 £477). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of £926). 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 7 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 £502 and £709 in October.The cheapest return price found within the last 5 days was £465 on Icelandair (16 Oct–14 Nov).
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 7 August 2026.
The most flights from SEA to LHR are scheduled on a Tuesday (25 on average). You will have fewer flight options on Saturday, 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.
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 7 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 23 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 £701, 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 £367. Other airlines that can offer you cheap pricing are British Airways, from £459, and Alaska Airlines, from £490. You may be able to fly from Seattle to London Heathrow Airport for 41% 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 £127 on Icelandair. Other airlines that offer cheap prices include Virgin Atlantic from £217 and British Airways from £242 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 £529, our data shows the cheapest flight currently is £241. When looking at the most popular route, (Seattle/Tacoma Intl - London Heathrow), you can expect to pay £416 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 £477). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of £926). 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 7 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 7 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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