$292+ Cheap flights from Seattle (SEA) to Heathrow (LHR)
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 7/14. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — LHR
Jul 27 — Aug 31
Round-trip
1 adult, Economy
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Find cheap flights from Seattle to Heathrow with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London Heathrow are usually found in January or February, booked 65 days in advance, depart on a Wednesday or Tuesday and return on a Monday
Cheap flight deals from Seattle to Heathrow
Cheapest
Best
Last-minute
One-way
Cheapest flights from Seattle to HeathrowExplore 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 June 27, 2026.
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 June 27, 2026.
This FlightHub deal was found by Cheapflights users on 6/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/152:35 pm
SEA
- LHR
1 stop12h 15m
Icelandair
Fri 12/2512:15 pm
LHR
- SEA
1 stop12h 45m
Icelandair
Deal found 6/27![Icelandair logo]()
$710
This Gotogate deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/253:40 pm
SEA
- LHR
1 stop20h 40m
Icelandair
Tue 9/89:25 pm
LHR
- SEA
1 stop22h 20m
Icelandair
Deal found 6/26![Icelandair logo]()
$713
This Cheapflightsfares deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/2411:25 pm
SEA
- LHR
1 stop12h 55m
Icelandair
Mon 9/79:25 pm
LHR
- SEA
1 stop22h 20m
Icelandair
Deal found 6/26![Icelandair logo]()
$714
This FlightHub deal was found by Cheapflights users on 6/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/307:00 pm
SEA
- LHR
1 stop17h 20m
Icelandair
Thu 10/2912:15 pm
LHR
- SEA
1 stop12h 45m
Icelandair
Deal found 6/27![Icelandair logo]()
$715
This oojo deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/263:40 pm
SEA
- LHR
1 stop12h 15m
Icelandair
Thu 10/89:25 pm
LHR
- SEA
1 stop28h 30m
Icelandair
Deal found 6/26![Icelandair logo]()
$716
This oojo deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/97:00 pm
SEA
- LHR
1 stop17h 20m
Icelandair
Wed 9/239:25 pm
LHR
- SEA
1 stop31h 15m
Icelandair
Deal found 6/26![Icelandair logo]()
$717
This deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/263:40 pm
SEA
- LHR
1 stop12h 15m
Icelandair
Sun 10/111:05 pm
LHR
- SEA
1 stop12h 50m
Icelandair
Deal found 6/26![Icelandair logo]()
$718
This oojo deal was found by Cheapflights users on 6/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/2211:25 pm
SEA
- LHR
1 stop28h 30m
Icelandair
Mon 8/319:25 pm
LHR
- SEA
1 stop22h 20m
Icelandair
Deal found 6/27![Icelandair logo]()
$721
This oojo deal was found by Cheapflights users on 6/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/77:00 pm
SEA
- LHR
1 stop17h 20m
Icelandair
Mon 9/149:25 pm
LHR
- SEA
1 stop31h 15m
Icelandair
Deal found 6/27![Icelandair logo]()
$722
This oojo deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/67:00 pm
SEA
- LHR
1 stop17h 20m
Icelandair
Sat 9/269:25 pm
LHR
- SEA
1 stop31h 15m
Icelandair
Deal found 6/26![Icelandair logo]()
$723
This Kiwi.com deal was found by Cheapflights users on 6/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/287:52 am
SEA
- LHR
2 stops16h 13m
Multiple Airlines
Mon 11/26:30 am
LHR
- SEA
1 stop13h 30m
Multiple Airlines
Deal found 6/27![Multiple Airlines logo]()
$724
This oojo deal was found by Cheapflights users on 6/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/511:25 pm
SEA
- LHR
1 stop28h 30m
Icelandair
Sat 9/199:25 pm
LHR
- SEA
1 stop31h 15m
Icelandair
Deal found 6/27![Icelandair logo]()
$726
Best flights from Seattle to HeathrowDiscover carefully curated flight deals from Seattle to Heathrow that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 27, 2026.
Discover carefully curated flight deals from Seattle to Heathrow that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 27, 2026.
This Alaska Airlines deal was found by Cheapflights users on 6/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/287:55 pm
SEA
- LHR
Nonstop9h 25m
Alaska Airlines
Wed 11/182:45 pm
LHR
- SEA
Nonstop10h 05m
Alaska Airlines
Deal found 6/22![Alaska Airlines logo]()
$860
This KLM deal was found by Cheapflights users on 6/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/259:50 pm
SEA
- LHR
Nonstop9h 45m
KLM
Thu 10/86:30 am
LHR
- SEA
1 stop13h 22m
KLM
Deal found 6/22![KLM logo]()
$881
This Delta deal was found by Cheapflights users on 6/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/2610:40 pm
SEA
- LHR
1 stop13h 30m
Delta
Wed 10/2812:20 pm
LHR
- SEA
Nonstop10h 30m
Delta
Deal found 6/24![Delta logo]()
$882
This United Airlines deal was found by Cheapflights users on 6/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/255:00 am
SEA
- LHR
2 stops16h 55m
United Airlines
Wed 8/266:00 pm
LHR
- SEA
2 stops26h 48m
United Airlines
Deal found 6/25![United Airlines logo]()
$946
This British Airways deal was found by Cheapflights users on 6/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/171:25 pm
SEA
- LHR
Nonstop9h 35m
British Airways
Tue 12/299:25 am
LHR
- SEA
Nonstop10h 05m
British Airways
Deal found 6/23![British Airways logo]()
$1,134
This Virgin Atlantic deal was found by Cheapflights users on 6/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/259:50 pm
SEA
- LHR
Nonstop9h 45m
Virgin Atlantic
Fri 7/315:45 pm
LHR
- SEA
Nonstop10h 18m
Virgin Atlantic
Deal found 6/24![Virgin Atlantic logo]()
$1,171
This TAP AIR PORTUGAL deal was found by Cheapflights users on 6/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure TAP AIR PORTUGAL is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/2011:55 pm
SEA
- LHR
2 stops28h 50m
TAP AIR PORTUGAL
Tue 10/278:15 am
LHR
- SEA
3 stops33h 50m
TAP AIR PORTUGAL
Deal found 6/22![TAP AIR PORTUGAL logo]()
$1,621
This Delta deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/139:45 pm
SEA
- LHR
Nonstop9h 50m
Delta
Wed 8/199:55 am
LHR
- SEA
1 stop14h 32m
Delta
Deal found 6/26![Delta logo]()
$947
This Delta deal was found by Cheapflights users on 6/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/219:50 pm
SEA
- LHR
Nonstop9h 45m
Delta
Fri 7/246:30 am
LHR
- SEA
1 stop13h 03m
Delta
Deal found 6/23![Delta logo]()
$1,064
This Delta deal was found by Cheapflights users on 6/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/106:20 pm
SEA
- LHR
Nonstop9h 50m
Delta
Mon 7/135:35 pm
LHR
- SEA
1 stop25h 40m
Delta
Deal found 6/23![Delta logo]()
$1,340
This TAP AIR PORTUGAL deal was found by Cheapflights users on 6/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure TAP AIR PORTUGAL is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/2511:55 pm
SEA
- LHR
2 stops26h 25m
TAP AIR PORTUGAL
Sat 10/1011:20 am
LHR
- SEA
3 stops43h 18m
TAP AIR PORTUGAL
Deal found 6/24![TAP AIR PORTUGAL logo]()
$1,644
Last-minute flights from Seattle to HeathrowDiscover last-minute flight deals from Seattle to Heathrow. Data last updated June 27, 2026 and is based on user searches.
Discover last-minute flight deals from Seattle to Heathrow. Data last updated June 27, 2026 and is based on user searches.
This Expedia deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/1010:19 pm
SEA
- LHR
1 stop14h 26m
Multiple Airlines
Thu 9/109:50 am
LHR
- SEA
Nonstop9h 45m
Multiple Airlines
Deal found 6/26![Multiple Airlines logo]()
$849
This Cheapflightsfares deal was found by Cheapflights users on 6/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/103:40 pm
SEA
- LHR
1 stop12h 15m
Icelandair
Tue 9/89:25 pm
LHR
- SEA
1 stop22h 20m
Icelandair
Deal found 6/24![Icelandair logo]()
$853
This Mytrip deal was found by Cheapflights users on 6/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/143:40 pm
SEA
- LHR
2 stops20h 40m
Multiple Airlines
Tue 8/117:40 am
LHR
- SEA
3 stops34h 00m
Multiple Airlines
Deal found 6/25![Multiple Airlines logo]()
$803
This Cheapflightsfares deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/2011:25 pm
SEA
- LHR
1 stop12h 55m
Icelandair
Wed 8/129:25 pm
LHR
- SEA
1 stop22h 20m
Icelandair
Deal found 6/26![Icelandair logo]()
$792
This Mytrip deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/243:40 pm
SEA
- LHR
2 stops20h 40m
Multiple Airlines
Sun 9/279:25 pm
LHR
- SEA
1 stop28h 30m
Multiple Airlines
Deal found 6/26![Multiple Airlines logo]()
$735
This Kiwi.com deal was found by Cheapflights users on 6/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/2511:25 pm
SEA
- LHR
2 stops32h 35m
Multiple Airlines
Sat 9/129:00 am
LHR
- SEA
1 stop15h 59m
Multiple Airlines
Deal found 6/25![Multiple Airlines logo]()
$834
This Kiwi.com deal was found by Cheapflights users on 6/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/263:40 pm
SEA
- LHR
1 stop12h 15m
Icelandair
Thu 8/69:25 pm
LHR
- SEA
1 stop28h 30m
Icelandair
Deal found 6/25![Icelandair logo]()
$847
This Mytrip deal was found by Cheapflights users on 6/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/283:40 pm
SEA
- LHR
2 stops18h 00m
Multiple Airlines
Tue 8/115:00 pm
LHR
- SEA
2 stops26h 45m
Multiple Airlines
Deal found 6/27![Multiple Airlines logo]()
$824
This Kiwi.com deal was found by Cheapflights users on 6/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/287:00 pm
SEA
- LHR
1 stop32h 55m
Icelandair
Thu 8/69:25 pm
LHR
- SEA
1 stop28h 30m
Icelandair
Deal found 6/25![Icelandair logo]()
$825
This Kiwi.com deal was found by Cheapflights users on 6/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/2811:25 pm
SEA
- LHR
2 stops25h 55m
Multiple Airlines
Mon 8/2412:00 pm
LHR
- SEA
1 stop13h 10m
Multiple Airlines
Deal found 6/24![Multiple Airlines logo]()
$855
One-way flights from Seattle to HeathrowSearch for one-way flight options from Seattle to Heathrow. Find affordable one-way fares based on user searches. Data last updated June 27, 2026.
Search for one-way flight options from Seattle to Heathrow. Find affordable one-way fares based on user searches. Data last updated June 27, 2026.
This Kiwi.com deal was found by Cheapflights users on 6/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/143:40 pm
SEA
- LHR
2 stops33h 25m
Multiple Airlines
Deal found 6/25![Multiple Airlines logo]()
$292
This oojo deal was found by Cheapflights users on 6/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/511:25 pm
SEA
- LHR
1 stop12h 55m
Icelandair
Deal found 6/27![Icelandair logo]()
$294
This Kiwi.com deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/1311:25 pm
SEA
- LHR
2 stops30h 30m
Multiple Airlines
Deal found 6/26![Multiple Airlines logo]()
$295
This oojo deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/17:00 pm
SEA
- LHR
1 stop32h 55m
Icelandair
Deal found 6/26![Icelandair logo]()
$296
This Mytrip deal was found by Cheapflights users on 6/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/263:40 pm
SEA
- LHR
1 stop12h 15m
Icelandair
Deal found 6/25![Icelandair logo]()
$297
This Gotogate deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/1011:25 pm
SEA
- LHR
1 stop12h 55m
Icelandair
Deal found 6/26![Icelandair logo]()
$298
This Kiwi.com deal was found by Cheapflights users on 6/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/303:40 pm
SEA
- LHR
2 stops20h 40m
Multiple Airlines
Deal found 6/24![Multiple Airlines logo]()
$299
This Kiwi.com deal was found by Cheapflights users on 6/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/213:40 pm
SEA
- LHR
1 stop12h 15m
Icelandair
Deal found 6/24![Icelandair logo]()
$300
This FlightHub deal was found by Cheapflights users on 6/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/227:00 pm
SEA
- LHR
1 stop32h 55m
Icelandair
Deal found 6/26![Icelandair logo]()
$304
This Kiwi.com deal was found by Cheapflights users on 6/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/1411:25 pm
SEA
- LHR
2 stops25h 55m
Multiple Airlines
Deal found 6/24![Multiple Airlines logo]()
$305
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 June 27, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $710 (FlightHub) |
One-way from | $292 (Kiwi.com) |
Popular in | June |
Cheapest in | January |
Average price | $1,214 |
Good round-trip deal | $976 or less |
Good one-way deal | $413 or less |
Cheapflights Fare Finder
Customize 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 2,558,603 searches. Data last updated June 27, 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
Cheapest round-trip
Quickest round-trip
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Wed 10/28
7:55 pm-12:20 pm
Nonstop9h 25m
London Heathrow
Wed 11/18
2:45 pm-4:50 pm
Nonstop10h 05m
$860
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Fri 9/25
9:50 pm-3:35 pm
Nonstop9h 45m
London Heathrow
Thu 10/8
6:30 am-11:52 am
1 stop13h 22m
$881
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sat 9/26
10:40 pm-8:10 pm
1 stop13h 30m
London Heathrow
Wed 10/28
12:20 pm-3:50 pm
Nonstop10h 30m
$882
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Tue 8/25
5:00 am-5:55 am
2 stops16h 55m
London Heathrow
Wed 8/26
6:00 pm-12:48 pm
2 stops26h 48m
$946
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Thu 8/13
9:45 pm-3:35 pm
Nonstop9h 50m
London Heathrow
Wed 8/19
9:55 am-4:27 pm
1 stop14h 32m
$947
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Tue 7/21
9:50 pm-3:35 pm
Nonstop9h 45m
London Heathrow
Fri 7/24
6:30 am-11:33 am
1 stop13h 03m
$1,064
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Thu 12/17
1:25 pm-7:00 am
Nonstop9h 35m
London Heathrow
Tue 12/29
9:25 am-11:30 am
Nonstop10h 05m
$1,134
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sat 7/25
9:50 pm-3:35 pm
Nonstop9h 45m
London Heathrow
Fri 7/31
5:45 pm-8:03 pm
Nonstop10h 18m
$1,171
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Fri 7/10
6:20 pm-12:10 pm
Nonstop9h 50m
London Heathrow
Mon 7/13
5:35 pm-11:15 am
1 stop25h 40m
$1,340
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Tue 10/20
11:55 pm-12:45 pm
2 stops28h 50m
London Heathrow
Tue 10/27
8:15 am-11:05 am
3 stops33h 50m
$1,621
Showing 1-10 of 23 resultsSorted by cheapest first
Compare providers for flights from Seattle to Heathrow
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Heathrow in June.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy- | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Seattle-London Heathrow Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-London Heathrow Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-London Heathrow Airport flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Seattle-London Heathrow Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-London Heathrow Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
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 round-trip 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
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Delays
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How far ahead should I book a flight from Seattle to London Heathrow Airport?
Booking 64 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to London Heathrow Airport. 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 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 $642). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of $1,235). 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 June 27, 2026.
Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Seattle to London Heathrow Airport as you normally would.
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 128 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 last year, Virgin Atlantic have had the lowest number of delays on this route, with just 6% of flights being delayed.
What’s the top layover airport for flights from Seattle to London Heathrow Airport?
Share of 1-stop round-trip flights from Seattle to London Heathrow Airport chosen by Cheapflights users in the past 12 months, using the same layover each way.
Reykjavik (KEF) – chosen by Cheapflights users on 79% of 1-stop itineraries from Seattle to London Heathrow Airport on Cheapflights.
What’s the cheapest layover airport for flights from Seattle to London Heathrow Airport?
Average round-trip fare for 1-stop flights from Seattle to London Heathrow Airport, chosen by Cheapflights users in the past 12 months, with the same layover each way.
Montreal (YUL) is the most affordable 1-stop option, with an average round-trip price of $631.
What’s the fastest layover option from Seattle to London Heathrow Airport?
Shortest average travel time for 1-stop one-way flights from Seattle to London Heathrow Airport, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.
Flights via Reykjavik (KEF) have the shortest average one-way travel time for 1-stop routes: 12h 21m.
Which airport typically offers the quickest layover for flights from Seattle to London Heathrow Airport?
Average layover duration for 1-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 layover time of 1h 50m.
The best insider tips for Seattle to London Heathrow Airport flights
AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to London Heathrow Airport trip
Our travel experts
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 June 27, 2026.
Read reviews from past customers who have flown Delta,Air France, andVirgin Atlantic from Seattle to London Heathrow Airport. 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.
Crew
8.5
Entertainment
7.8
Boarding
8.1
Food
7.2
Comfort
7.8
Overall
7.8
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Entertainment
7.8
Boarding
8.1
Food
7.2
Comfort
7.8
Overall
7.8
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Entertainment
7.8
Boarding
8.1
Food
7.2
Comfort
7.8
Overall
7.8
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Entertainment
7.8
Boarding
8.1
Food
7.2
Comfort
7.8
Overall
7.8
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Entertainment
7.8
Boarding
8.1
Food
7.2
Comfort
7.8
Overall
7.8
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
Crew
8.5
Entertainment
7.8
Boarding
8.1
Food
7.2
Comfort
7.8
Overall
7.8
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2026
SEA - KOA
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.
Traveling to a place near London Heathrow Airport?
Book flights to London Heathrow Airport if you plan to visit one of these locationsIlford
Dorking
Hounslow
Winchester
Croydon
Gatwick
Southend-on-Sea
Wembley
Harrow
Eastleigh
Dartford
Dover
Orpington
Watford
Northampton
Chipping Norton
Hayes
Kingston upon Thames
Eastbourne
Slough
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Other flights to Heathrow
Explore flights to Heathrow departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on June 27, 2026.
Seattle and Heathrow flights
Browse other Seattle and Heathrow flight options. Last updated on June 27, 2026.
Other flights from Seattle
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Top 10 airlines flying from Seattle to Heathrow
Discover the top 10 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 2,558,603 searches. Data last updated June 27, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$480 | Average$697 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$484 | Average$678 | FlexibilityNo cancel fee | On-time76% | |
| Cheapest$515 | Average$785 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$517 | Average$749 | FlexibilityNo cancel fee | On-time77% | |
| Cheapest$519 | Average$742 | FlexibilityNo cancel fee | On-time70% | |
| Cheapest$541 | Average$875 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$547 | Average$816 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$556 | Average$694 | FlexibilityNo cancel fee | On-time76% | |
| Cheapest$565 | Average$939 | FlexibilityNo cancel fee | On-time72% | |
| Cheapest$608 | Average$1,112 | FlexibilityNo cancel fee | On-time75% |