
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $542 (CrystalTravel) |
One-way from | $375 (Kiwi.com) |
Popular in | June |
Cheapest in | January |
Average price | $690 |
Good round-trip deal | $650 or less |
Good one-way deal | $377 or less |
Fly from
Fly to
Route
Depart
Return
Price
SeattleLondon
SEA - LGW
SEALGW
Seattle/Tacoma Intl
Thu 4/23
7:00 pm-2:40 pm
1 stop11h 40m
London Gatwick
Sun 5/10
3:40 pm-5:55 pm
1 stop34h 15m
SeattleLondon
SEA - LTN
SEALTN
Seattle/Tacoma Intl
Mon 4/20
5:40 am-2:20 pm
3 stops24h 40m
London Luton
Tue 4/28
5:40 am-10:50 pm
3 stops25h 10m
SeattleLondon
SEA - LTN
SEALTN
Seattle/Tacoma Intl
Mon 4/13
5:40 am-11:00 am
3 stops21h 20m
London Luton
Mon 4/20
5:40 am-9:53 pm
2 stops24h 13m
SeattleLondon
SEA - LTN
SEALTN
Seattle/Tacoma Intl
Fri 4/24
3:40 pm-9:05 pm
2 stops21h 25m
London Luton
Tue 4/28
9:15 am-8:40 pm
2 stops19h 25m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 3/30
9:45 pm-3:35 pm
Nonstop9h 50m
London Heathrow
Wed 4/8
11:45 am-4:30 pm
1 stop12h 45m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 3/23
5:40 pm-10:30 am
Nonstop9h 50m
London Heathrow
Wed 4/8
11:45 am-4:30 pm
1 stop12h 45m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Mon 5/4
9:45 pm-3:35 pm
Nonstop9h 50m
London Heathrow
Tue 5/19
6:30 am-11:42 am
1 stop13h 12m
SeattleLondon
SEA - SEN
SEASEN
Seattle/Tacoma Intl
Wed 3/4
2:35 pm-9:00 pm
2 stops22h 25m
London Southend
Wed 3/18
7:10 am-6:00 pm
2 stops17h 50m
SeattleLondon
SEA - LTN
SEALTN
Seattle/Tacoma Intl
Sat 3/21
8:00 am-2:00 pm
3 stops23h 00m
London Luton
Sun 3/29
8:35 pm-9:53 pm
3 stops33h 18m
SeattleLondon
SEA - LHR
SEALHR
Seattle/Tacoma Intl
Tue 3/17
5:20 pm-12:00 pm
1 stop35h 40m
London Heathrow
Mon 3/23
6:00 pm-10:16 pm
1 stop35h 16m
| 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 Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*2 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*2 stars |
Booking 9 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to London. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
Currently, February is the cheapest month in which you can book a flight from Seattle to London (average of $494). Flying from Seattle to London in June is currently the most expensive (average of $775). 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 as you normally would.
The most flights from SEA to LON are scheduled on a Saturday (21 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (12 on average).
Reykjavik (KEF) – chosen by Cheapflights users on 78% of 1-stop itineraries from Seattle to London on Cheapflights.
Reykjavik (KEF) is the most affordable 1-stop option, with an average round-trip price of $533.
Flights via Dublin (DUB) have the shortest average one-way travel time for 1-stop routes: 11h 35m.
Flights via Dublin (DUB) offer the fastest connection on this route, with an average layover time of 1h 30m.
About 16% of weekly flights between Seattle and London have experienced delays in the past year, with the average delay time being 123 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 6% of flights being delayed.
Boarding
Food
Comfort
Entertainment
Crew
Overall
Reviews
Jim,Nov 2025
AVL - ATL
Boarding
Food
Comfort
Entertainment
Crew
Overall
Reviews
Jim,Nov 2025
AVL - ATL
Boarding
Food
Comfort
Entertainment
Crew
Overall
Reviews
Jim,Nov 2025
AVL - ATL
Boarding
Food
Comfort
Entertainment
Crew
Overall
Reviews
Jim,Nov 2025
AVL - ATL
Boarding
Food
Comfort
Entertainment
Crew
Overall
Reviews
Jim,Nov 2025
AVL - ATL
Boarding
Food
Comfort
Entertainment
Crew
Overall
Reviews
Jim,Nov 2025
AVL - ATL
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$465 | Average$871 | FlexibilityNo cancel fee | On-time77% | |
| Cheapest$483 | Average$631 | FlexibilityNo cancel fee | On-time76% | |
| Cheapest$500 | Average$720 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$517 | Average$804 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$532 | Average$757 | FlexibilityNo cancel fee | On-time77% | |
| Cheapest$533 | Average$754 | FlexibilityNo cancel fee | On-time70% | |
| Cheapest$547 | Average$824 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$556 | Average$694 | FlexibilityNo cancel fee | On-time76% | |
| Cheapest$557 | Average$839 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$565 | Average$999 | FlexibilityNo cancel fee | On-time75% |