Cheap flights from Seattle to London Heathrow Airport from £258
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 29/12. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — LHR
11 Jan — 18 Jan1
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 October or March, booked 65 days in advance, depart on a Tuesday or Thursday and return on a Wednesday
Cheap flight deals from Seattle to Heathrow
Enter your travel dates to find the best prices.
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 December 2025.
Wed 31/1215:40SEA - LHR
1 stop12h 10mLufthansa
Mon 12/119:30LHR - SEA
2 stops30h 44mLufthansa
Deal found 11/12£527
Fri 26/1210:05SEA - LHR
1 stop17h 45mLufthansa
Fri 23/106:35LHR - SEA
1 stop14h 45mLufthansa
Deal found 11/12£550
Mon 29/1220:00SEA - LHR
1 stop31h 50mUnited Airlines
Thu 8/106:30LHR - SEA
2 stops23h 46mUnited Airlines
Deal found 11/12£554
Mon 29/1220:00SEA - LHR
1 stop31h 50mMultiple Airlines
Thu 8/113:00LHR - SEA
1 stop17h 16mMultiple Airlines
Deal found 11/12£557
Tue 30/1205:50SEA - LHR
2 stops16h 40mAir Canada
Wed 7/114:30LHR - SEA
1 stop26h 45mAir Canada
Deal found 11/12£568
Tue 23/1220:00SEA - LHR
1 stop31h 50mMultiple Airlines
Sat 31/106:30LHR - SEA
1 stop13h 40mMultiple Airlines
Deal found 9/12£571
Wed 31/1213:35SEA - LHR
1 stop12h 25mMultiple Airlines
Mon 12/106:20LHR - SEA
1 stop15h 05mMultiple Airlines
Deal found 10/12£572
Sat 27/1220:00SEA - LHR
1 stop31h 50mAir Canada
Wed 7/114:30LHR - SEA
1 stop26h 45mAir Canada
Deal found 11/12£577
Fri 26/1205:50SEA - LHR
1 stop22h 00mMultiple Airlines
Fri 23/106:35LHR - SEA
1 stop14h 45mMultiple Airlines
Deal found 11/12£577
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 December 2025.
Sun 8/310:05SEA - LHR
2 stops18h 15mLufthansa
Wed 18/307:40LHR - SEA
1 stop13h 40mLufthansa
Deal found 11/12£440
Mon 11/519:00SEA - LHR
1 stop32h 55mIcelandair
Sat 23/521:25LHR - SEA
1 stop22h 20mIcelandair
Deal found 11/12£451
Sat 14/218:25SEA - LHR
Nonstop9h 30mDelta
Sun 22/211:45LHR - SEA
1 stop31h 55mDelta
Deal found 11/12£459
Tue 10/317:40SEA - LHR
Nonstop9h 50mKLM
Tue 17/306:30LHR - SEA
1 stop13h 05mKLM
Deal found 11/12£459
Sun 18/120:00SEA - LHR
1 stop31h 50mUnited Airlines
Sat 31/106:35LHR - SEA
2 stops22h 40mUnited Airlines
Deal found 11/12£465
Tue 17/211:17SEA - LHR
2 stops22h 23mScandinavian Airlines
Wed 25/210:20LHR - SEA
2 stops21h 05mScandinavian Airlines
Deal found 10/12£469
Thu 8/118:50SEA - LHR
Nonstop9h 30mBritish Airways
Wed 21/114:55LHR - SEA
Nonstop10h 00mBritish Airways
Deal found 10/12£479
Sun 8/317:40SEA - LHR
Nonstop9h 50mDelta
Wed 18/306:30LHR - SEA
1 stop13h 05mDelta
Deal found 10/12£459
Mon 2/215:40SEA - LHR
1 stop12h 10mUnited Airlines
Mon 9/206:30LHR - SEA
1 stop13h 40mUnited Airlines
Deal found 11/12£466
Mon 4/515:00SEA - LHR
1 stop14h 20mLufthansa
Tue 19/506:30LHR - SEA
1 stop13h 50mLufthansa
Deal found 10/12£478
Thu 8/108:40SEA - LHR
2 stops17h 45mUnited Airlines
Tue 10/306:50LHR - SEA
2 stops19h 13mUnited Airlines
Deal found 10/12£468
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 December 2025.
Thu 15/118:25SEA - LHR
Nonstop9h 30mVirgin Atlantic
Sat 31/115:05LHR - SEA
Nonstop10h 05mVirgin Atlantic
Deal found 10/12£457
Thu 15/118:50SEA - LHR
Nonstop9h 30mBritish Airways
Sat 24/109:25LHR - SEA
Nonstop10h 05mBritish Airways
Deal found 11/12£462
Sat 31/113:35SEA - LHR
Nonstop9h 35mFinnair
Mon 16/214:55LHR - SEA
Nonstop10h 00mFinnair
Deal found 10/12£464
Wed 21/118:50SEA - LHR
Nonstop9h 30mBritish Airways
Fri 30/114:55LHR - SEA
Nonstop10h 00mBritish Airways
Deal found 11/12£468
Thu 5/218:50SEA - LHR
Nonstop9h 30mFinnair
Sun 8/214:55LHR - SEA
Nonstop10h 00mFinnair
Deal found 10/12£470
Sat 24/118:25SEA - LHR
Nonstop9h 30mVirgin Atlantic
Sat 31/115:05LHR - SEA
Nonstop10h 05mVirgin Atlantic
Deal found 9/12£471
Sun 15/218:50SEA - LHR
Nonstop9h 30mFinnair
Thu 26/214:55LHR - SEA
Nonstop10h 00mFinnair
Deal found 10/12£472
Fri 23/118:50SEA - LHR
Nonstop9h 30mBritish Airways
Fri 30/114:55LHR - SEA
Nonstop10h 00mBritish Airways
Deal found 9/12£473
Sun 1/218:50SEA - LHR
Nonstop9h 30mFinnair
Mon 9/214:55LHR - SEA
Nonstop10h 00mFinnair
Deal found 11/12£475
Mon 12/118:25SEA - LHR
Nonstop9h 30mMultiple Airlines
Sun 18/112:20LHR - SEA
Nonstop10h 29mMultiple Airlines
Deal found 10/12£479
Mon 20/420:20SEA - LHR
Nonstop9h 25mBritish Airways
Tue 28/409:50LHR - SEA
Nonstop9h 45mBritish Airways
Deal found 10/12£480
Last-minute flights from Seattle to Heathrow
Discover last-minute flight deals from Seattle to Heathrow. Data last updated 12 December 2025 and is based on user searches.
Thu 8/114:10SEA - LHR
1 stop13h 05mLufthansa
Thu 15/106:30LHR - SEA
1 stop13h 40mLufthansa
Deal found 11/12£434
Thu 8/115:40SEA - LHR
1 stop12h 10mLufthansa
Tue 10/320:15LHR - SEA
1 stop25h 05mLufthansa
Deal found 10/12£442
Fri 9/114:35SEA - LHR
1 stop20h 55mIcelandair
Mon 19/120:35LHR - SEA
1 stop28h 25mIcelandair
Deal found 11/12£435
Sat 10/114:35SEA - LHR
1 stop12h 15mIcelandair
Fri 23/112:15LHR - SEA
1 stop12h 45mIcelandair
Deal found 11/12£433
Sat 10/120:00SEA - LHR
2 stops30h 10mMultiple Airlines
Sun 25/107:40LHR - SEA
1 stop13h 40mMultiple Airlines
Deal found 11/12£441
Wed 14/108:10SEA - LHR
2 stops19h 05mAustrian Airlines
Sun 18/112:05LHR - SEA
1 stop16h 52mAustrian Airlines
Deal found 10/12£440
Wed 14/115:40SEA - LHR
1 stop12h 10mMultiple Airlines
Sun 18/107:40LHR - SEA
2 stops19h 36mMultiple Airlines
Deal found 9/12£447
Fri 16/105:50SEA - LHR
2 stops17h 20mMultiple Airlines
Sun 18/107:40LHR - SEA
2 stops19h 36mMultiple Airlines
Deal found 11/12£441
Wed 21/109:55SEA - LHR
2 stops16h 15mLufthansa
Sun 25/107:40LHR - SEA
1 stop13h 40mLufthansa
Deal found 11/12£435
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 December 2025.
Mon 29/1214:35SEA - LHR
1 stop20h 55mIcelandair
Deal found 11/12£258
Sat 10/114:49SEA - LHR
3 stops42h 41mMultiple Airlines
Deal found 9/12£258
Mon 23/311:55SEA - LHR
2 stops17h 55mWestJet
Deal found 10/12£260
Sun 22/321:35SEA - LHR
2 stops32h 05mMultiple Airlines
Deal found 10/12£261
Sun 11/108:32SEA - LHR
2 stops20h 18mMultiple Airlines
Deal found 11/12£261
Tue 10/315:11SEA - LHR
2 stops37h 14mMultiple Airlines
Deal found 9/12£263
Tue 13/107:10SEA - LHR
2 stops18h 10mScandinavian Airlines
Deal found 11/12£269
Fri 9/117:38SEA - LHR
3 stops41h 17mMultiple Airlines
Deal found 10/12£270
Sun 11/107:00SEA - LHR
2 stops18h 40mLufthansa
Deal found 9/12£272
Sat 7/210:09SEA - LHR
2 stops23h 21mMultiple Airlines
Deal found 9/12£273
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 December 2025.
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 December 2025.
Use the filters below to find and compare flights from Seattle to London Heathrow Airport that are best for you.
Fly from
Seattle
Fly to
Heathrow
Route
Depart
Return
Price
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sun 8/3
10:05-11:20
2 stops18h 15m
London Heathrow
Wed 18/3
07:40-14:20
1 stop13h 40m
£440
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 11/5
19:00-11:55
1 stop32h 55m
London Heathrow
Sat 23/5
21:25-11:45
1 stop22h 20m
£451
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sat 14/2
18:25-11:55
Nonstop9h 30m
London Heathrow
Sun 22/2
11:45-11:40
1 stop31h 55m
£459
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Tue 10/3
17:40-10:30
Nonstop9h 50m
London Heathrow
Tue 17/3
06:30-12:35
1 stop13h 05m
£459
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sun 8/3
17:40-10:30
Nonstop9h 50m
London Heathrow
Wed 18/3
06:30-12:35
1 stop13h 05m
£459
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sun 18/1
20:00-11:50
1 stop31h 50m
London Heathrow
Sat 31/1
06:35-21:15
2 stops22h 40m
£465
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 2/2
15:40-11:50
1 stop12h 10m
London Heathrow
Mon 9/2
06:30-12:10
1 stop13h 40m
£466
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Thu 8/1
08:40-10:25
2 stops17h 45m
London Heathrow
Tue 10/3
06:50-19:03
2 stops19h 13m
£468
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Tue 17/2
11:17-17:40
2 stops22h 23m
London Heathrow
Wed 25/2
10:20-23:25
2 stops21h 05m
£469
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 4/5
15:00-13:20
1 stop14h 20m
London Heathrow
Tue 19/5
06:30-12:20
1 stop13h 50m
£478
Flights are sorted by cheapest return flights first.
Deals found on 11/12
Showing 1-10 of 23 results
1
2
3
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.
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?
Use this chart to determine the optimal time to book a return flight from Seattle to Heathrow. Price data was last updated on 5 December 2025.
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 65 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, October is the cheapest month in which you can book a flight from Seattle to London Heathrow Airport (average of £371). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of £589). 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 December 2025.
Unlike in the morning, when flights are generally more expensive, you can save up to 46% on flights from Seattle to London Heathrow Airport by exploring options for tickets at midday.
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 December 2025.
The most flights from SEA to LHR are scheduled on a Thursday (15 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (10 on average).
How often are flights from Seattle to London delayed?
About 16% of weekly flights between Seattle and London have experienced delays in the past year, with the average delay time being 123 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 at night 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 Sunday 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.
Reykjavik (KEF) – 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.
Dublin (DUB) is the most affordable one-stop option, with an average return flight price of £442.
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 Dublin (DUB) have the shortest average one-way travel time for one-stop routes: 13h 50m.
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 Dublin (DUB) offer the fastest connection on this route, with an average stopover time of 2h 21m.
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 December 2025.
Read through reviews of airlines operating flights from Seattle to London Heathrow Airport, such as Virgin Atlantic and British Airways. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
The flight is clean, food good and the staff are excellent! Very professional, polite and accommodating. The seat itself is really mediocre. Can’t believe there is not inch of storage space. Believe it or not it there is not place even to put away your phone or pen!! Very very surprising and terribly inconvenient. No coat hanger hook either. Had to give it away. ALL IN ALL VERY INCONVENIENT business class seat compared to their peers. What is even more surprising is that this on their relatively new fleet of Airbus A350-1000. I was having com platelets different expectations of Virgin and this has disappointed me. Everything else is just as good and as you would expect from Virgin!
The flight is clean, food good and the staff are excellent! Very professional, polite and accommodating. The seat itself is really mediocre. Can’t believe there is not inch of storage space. Believe it or not it there is not place even to put away your phone or pen!! Very very surprising and terribly inconvenient. No coat hanger hook either. Had to give it away. ALL IN ALL VERY INCONVENIENT business class seat compared to their peers. What is even more surprising is that this on their relatively new fleet of Airbus A350-1000. I was having com platelets different expectations of Virgin and this has disappointed me. Everything else is just as good and as you would expect from Virgin!
The flight is clean, food good and the staff are excellent! Very professional, polite and accommodating. The seat itself is really mediocre. Can’t believe there is not inch of storage space. Believe it or not it there is not place even to put away your phone or pen!! Very very surprising and terribly inconvenient. No coat hanger hook either. Had to give it away. ALL IN ALL VERY INCONVENIENT business class seat compared to their peers. What is even more surprising is that this on their relatively new fleet of Airbus A350-1000. I was having com platelets different expectations of Virgin and this has disappointed me. Everything else is just as good and as you would expect from Virgin!
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 11 flights from Seattle/Tacoma Intl to London Heathrow per day from 2 different airlines.
How long is the flight from Seattle to London Heathrow Airport?
For as low as £459, Lufthansa can have you in London Heathrow Airport from Seattle in 9h 30m. 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 £354. Another airline that can offer you cheap pricing is Virgin Atlantic. You may be able to fly from Seattle to London Heathrow Airport for 40% 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 £164 on Icelandair. Other airlines that offer cheap prices include Virgin Atlantic from £293 and British Airways from £294 one-way.
What are the most reliable airlines from Seattle to London Heathrow Airport?
Consider KLM (87%), Delta (85%) or Virgin Atlantic (85%) 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 £801, our data shows the cheapest flight currently is £285. When looking at the most popular route, (Seattle/Tacoma Intl - London Heathrow), you can expect to pay £349 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, October is the cheapest month in which you can book a flight from Seattle to London Heathrow Airport (average of £371). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of £589). 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 December 2025.
Discover the top 2 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 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 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!
100% Free
Cheapflights is completely free to use, so you can start saving the moment you arrive.
Book with Flexibility
Our users can plan ahead with confidence and find flights with no change fees
Travel Smart
Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.
We value your privacy
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.
By clicking 'Accept', you consent to your data being processed by 0 vendors on this web site for the purposes described in this notice. You can review the vendors and their individual processing purposes on the .
To review individual processing purposes and cookie categories, please click ’Select individual purposes’. You can review your choices and withdraw your consent at any time by clicking the ’Privacy Preferences’ link in the page side navigation.