
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $564 (oojo) |
One-way from | $375 (Mytrip) |
Popular in | June |
Cheapest in | January |
Average price | $741 |
Good round-trip deal | $714 or less |
Good one-way deal | $414 or less |
Fly from
Fly to
Route
Depart
Return
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sun 8/23
9:55 pm-3:35 pm
Nonstop9h 40m
London Heathrow
Wed 9/2
6:30 am-11:47 am
1 stop13h 17m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 8/17
9:45 pm-3:05 pm
Nonstop9h 20m
London Heathrow
Tue 10/6
5:00 pm-6:55 pm
Nonstop9h 55m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sun 8/16
9:55 pm-3:35 pm
Nonstop9h 40m
London Heathrow
Tue 10/6
6:15 am-11:15 am
1 stop13h 00m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Thu 4/16
8:10 pm-2:00 pm
Nonstop9h 50m
London Heathrow
Thu 4/23
11:45 am-4:30 pm
1 stop12h 45m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 8/31
11:00 pm-9:35 pm
1 stop14h 35m
London Heathrow
Wed 9/16
6:55 am-4:59 pm
1 stop18h 04m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sat 5/2
5:25 pm-7:25 am
1 stop30h 00m
London Heathrow
Fri 5/22
5:40 pm-9:08 pm
1 stop35h 28m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Wed 9/2
6:20 pm-12:10 pm
Nonstop9h 50m
London Heathrow
Sun 9/13
6:15 am-11:15 am
1 stop13h 00m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Sun 4/5
6:53 am-6:20 am
1 stop15h 27m
London Heathrow
Mon 4/13
9:50 am-11:35 am
Nonstop9h 45m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 4/6
11:59 pm-8:35 am
2 stops24h 36m
London Heathrow
Mon 4/20
5:50 pm-7:00 pm
2 stops33h 10m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Tue 3/24
4:05 pm-1:50 pm
1 stop14h 45m
London Heathrow
Tue 3/31
11:30 am-5:38 pm
1 stop14h 08m
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*2 stars | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy1 star | Trust Score*2 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
Booking 26 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, October is the cheapest month in which you can book a flight from Seattle to London Heathrow Airport (average of $502). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of $756). 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.
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.
About 16% of weekly flights between Seattle and London have experienced delays in the past year, with the average delay time being 121 minutes.
Historically, flights departing in the early afternoon are less likely to be delayed, whereas flights leaving at night tend to experience delays more often.
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.
Over the last year, Virgin Atlantic have had the lowest number of delays on this route, with just 7% of flights being delayed.
Reykjavik (KEF) – chosen by Cheapflights users on 75% of 1-stop itineraries from Seattle to London Heathrow Airport on Cheapflights.
Montreal (YUL) is the most affordable 1-stop option, with an average round-trip price of $631.
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 2h 06m.
Overall
Crew
Comfort
Entertainment
Boarding
Food
Reviews
Jim,Nov 2025
AVL - ATL
Overall
Crew
Comfort
Entertainment
Boarding
Food
Reviews
Jim,Nov 2025
AVL - ATL
Overall
Crew
Comfort
Entertainment
Boarding
Food
Reviews
Jim,Nov 2025
AVL - ATL
Overall
Crew
Comfort
Entertainment
Boarding
Food
Reviews
Jim,Nov 2025
AVL - ATL
Overall
Crew
Comfort
Entertainment
Boarding
Food
Reviews
Jim,Nov 2025
AVL - ATL
Overall
Crew
Comfort
Entertainment
Boarding
Food
Reviews
Jim,Nov 2025
AVL - ATL
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$465 | Average$768 | FlexibilityNo cancel fee | On-time77% | |
| Cheapest$482 | Average$600 | FlexibilityNo cancel fee | On-time76% | |
| Cheapest$500 | Average$722 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$515 | Average$779 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$528 | Average$731 | FlexibilityNo cancel fee | On-time70% | |
| Cheapest$532 | Average$765 | FlexibilityNo cancel fee | On-time77% | |
| Cheapest$547 | Average$825 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$556 | Average$694 | FlexibilityNo cancel fee | On-time76% | |
| Cheapest$561 | Average$841 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$567 | Average$739 | FlexibilityNo cancel fee | On-time77% |