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Most accurate provider | eDreams 3 stars |
|---|---|
Most trusted provider | eDreams 3 stars |
Round-trip from | $525 (Gotogate) |
One-way from | $353 (Kiwi.com) |
Popular in | June |
Cheapest in | March |
Average price | $727 |
Good round-trip deal | $670 or less |
Good one-way deal | $472 or less |
Fly from
Fly to
Route
Depart
Return
Price
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 11/10
7:20 pm-12:50 pm
Nonstop9h 30m
London Heathrow
Tue 11/25
6:20 am-11:25 am
1 stop13h 05m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Wed 12/10
4:48 pm-10:30 am
Nonstop9h 42m
London Heathrow
Thu 12/25
6:30 am-11:50 am
1 stop13h 20m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 12/8
4:48 pm-10:30 am
Nonstop9h 42m
London Heathrow
Thu 12/25
6:30 am-11:50 am
1 stop13h 20m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sun 11/9
9:28 am-7:05 am
1 stop13h 37m
London Heathrow
Tue 11/25
12:20 pm-2:48 pm
Nonstop10h 28m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Wed 11/12
4:48 pm-10:30 am
Nonstop9h 42m
London Heathrow
Wed 11/26
12:20 pm-2:48 pm
Nonstop10h 28m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 12/8
6:50 pm-12:20 pm
Nonstop9h 30m
London Heathrow
Thu 12/25
2:55 pm-4:55 pm
Nonstop10h 00m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Wed 11/26
6:00 am-7:05 am
1 stop17h 05m
London Heathrow
Fri 12/5
12:20 pm-2:58 pm
Nonstop10h 38m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 1/12
6:50 pm-12:20 pm
Nonstop9h 30m
London Heathrow
Thu 1/22
2:55 pm-4:55 pm
Nonstop10h 00m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Tue 1/6
6:05 am-7:05 am
1 stop17h 00m
London Heathrow
Tue 1/20
12:20 pm-2:53 pm
Nonstop10h 33m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Tue 12/30
7:20 pm-12:50 pm
Nonstop9h 30m
London Heathrow
Fri 3/6
6:20 am-1:05 pm
1 stop14h 45m
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*2 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*2 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
Booking 89 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.
Currently, November is the cheapest month in which you can book a flight from Seattle to London Heathrow Airport (average of $487). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of $792). 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.
When flying from Seattle to London Heathrow Airport, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 15% versus a flight in the morning.
Travelers seeking maximum savings on their Seattle to London Heathrow Airport flight should consider departing on Monday mornings when fares are most often at their lowest. Thursday mornings flights should be avoided if possible as fares are typically the most expensive at this time.
About 17% of weekly flights between Seattle and London have experienced delays in the past year, with the average delay time being 131 minutes.
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.
Friday 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.
Over the last year, La Costena have had the lowest number of delays on this route, with no flights being classified as delayed.
Reykjavik (KEF) – chosen by Cheapflights users on 83% of 1-stop itineraries from Seattle to London Heathrow Airport on Cheapflights.
Flights via Dublin (DUB) have the shortest average one-way travel time for 1-stop routes: 12h 10m.
Flights via Dublin (DUB) have the shortest average one-way travel time for 1-stop routes: 12h 10m.
Flights via Reykjavik (KEF) offer the fastest connection on this route, with an average layover time of 1h 29m.
Crew
Food
Overall
Boarding
Entertainment
Comfort
Reviews
Jim,Nov 2025
AVL - ATL
Crew
Food
Overall
Boarding
Entertainment
Comfort
Reviews
Jim,Nov 2025
AVL - ATL
Crew
Food
Overall
Boarding
Entertainment
Comfort
Reviews
Jim,Nov 2025
AVL - ATL
Crew
Food
Overall
Boarding
Entertainment
Comfort
Reviews
Jim,Nov 2025
AVL - ATL
Crew
Food
Overall
Boarding
Entertainment
Comfort
Reviews
Jim,Nov 2025
AVL - ATL
Crew
Food
Overall
Boarding
Entertainment
Comfort
Reviews
Jim,Nov 2025
AVL - ATL
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$465 | Average$741 | FlexibilityNo cancel fee | On-time77% | |
| Cheapest$482 | Average$637 | FlexibilityNo cancel fee | On-time76% | |
| Cheapest$500 | Average$703 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$517 | Average$751 | FlexibilityNo cancel fee | On-time77% | |
| Cheapest$518 | Average$846 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$546 | Average$793 | FlexibilityNo cancel fee | On-time70% | |
| Cheapest$547 | Average$782 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$553 | Average$999 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$556 | Average$697 | FlexibilityNo cancel fee | On-time76% | |
| Cheapest$562 | Average$833 | FlexibilityNo cancel fee | On-timeN/A |