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Use the filters below to find and compare flights from London to Seattle that are best for you.
Fly from
Fly to
Route
Depart
Return
LondonSeattle
LHR London Heathrow - SEA Seattle/Tacoma Intl
LHRSEA
London Heathrow
Thu 29/10
14:45-18:05
Nonstop10h 20m
Seattle/Tacoma Intl
Wed 11/11
18:45-12:20
Nonstop9h 35m
LondonSeattle
LHR London Heathrow - SEA Seattle/Tacoma Intl
LHRSEA
London Heathrow
Fri 11/12
14:45-17:00
Nonstop10h 15m
Seattle/Tacoma Intl
Thu 24/12
18:55-12:20
Nonstop9h 25m
LondonSeattle
LHR London Heathrow - SEA Seattle/Tacoma Intl
LHRSEA
London Heathrow
Fri 11/12
14:45-17:00
Nonstop10h 15m
Seattle/Tacoma Intl
Wed 6/1
18:40-12:20
Nonstop9h 40m
LondonSeattle
LHR London Heathrow - SEA Seattle/Tacoma Intl
LHRSEA
London Heathrow
Thu 14/1
14:45-16:50
Nonstop10h 05m
Seattle/Tacoma Intl
Mon 18/1
18:40-12:20
Nonstop9h 40m
LondonSeattle
LHR London Heathrow - SEA Seattle/Tacoma Intl
LHRSEA
London Heathrow
Tue 12/1
14:45-16:50
Nonstop10h 05m
Seattle/Tacoma Intl
Wed 10/2
18:40-12:20
Nonstop9h 40m
LondonSeattle
LHR London Heathrow - SEA Seattle/Tacoma Intl
LHRSEA
London Heathrow
Mon 9/11
20:35-17:00
1 stop28h 25m
Seattle/Tacoma Intl
Thu 1/4
19:00-11:55
1 stop32h 55m
LondonSeattle
LHR London Heathrow - SEA Seattle/Tacoma Intl
LHRSEA
London Heathrow
Thu 1/4
17:00-19:10
Nonstop10h 10m
Seattle/Tacoma Intl
Sun 25/4
21:30-15:05
Nonstop9h 35m
LondonSeattle
LHR London Heathrow - SEA Seattle/Tacoma Intl
LHRSEA
London Heathrow
Mon 9/11
20:35-17:00
1 stop28h 25m
Seattle/Tacoma Intl
Sat 27/3
15:35-10:55
1 stop12h 20m
LondonSeattle
LHR London Heathrow - SEA Seattle/Tacoma Intl
LHRSEA
London Heathrow
Wed 21/10
21:25-17:55
1 stop28h 30m
Seattle/Tacoma Intl
Sun 25/10
19:10-10:50
1 stop32h 40m
LondonSeattle
LHR London Heathrow - SEA Seattle/Tacoma Intl
LHRSEA
London Heathrow
Mon 9/11
20:35-17:00
1 stop28h 25m
Seattle/Tacoma Intl
Mon 29/3
19:00-11:55
1 stop32h 55m
See travel insights to Seattle from
How to get the cheapest flight ticket from London to Seattle
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the typical price of a round-trip flight between London and Seattle?
Prices are currently low for flights on this route.
Typical prices usually range from €529 to €720.The lowest price recently found on this route was €495.
What is the cheapest month to fly to Seattle?
If you’re not able to fly to Seattle in February, then January is your next best option. Flight prices from London to Seattle during January average around €590.
What is the cheapest time of day to depart on your flight to Seattle?
Our data shows that the cheapest London to Seattle flights are usually those with departure times in the morning. Our users have found flights to Seattle in the morning for as low as €650. Flights in the afternoon are often more expensive, with an average ticket price of €666.
What is the cheapest London to Seattle/Tacoma Intl flight route?
Fly from London Heathrow to Seattle/Tacoma Intl for the best London - Seattle/Tacoma Intl flight prices
How far in advance should I book a flight from London to Seattle?
You are more likely to see cheaper flights to Seattle from London when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around €706 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from London for as low as €650 on momondo.
What cabin class options are available on London to Seattle flights?
There is only 1 cabin class available to choose from on London to Seattle flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
Can stopping save me money on London to Seattle flights?
No. A direct flight is the cheapest option for a flight between London to Seattle.
How often are flights from London to Seattle delayed?
Historically, on average around 12% of flights between London and Seattle have experienced a delay on any given week. The average delay length over the past 12 months has been 134 minutes.
What is the most punctual flight time for London to Seattle flights?
Generally, flights departing in the evening tend to experience fewer delays. Flights departing in the early afternoon have, in the past, seen delays more frequently in comparison.
What day of the week experiences the fewest flight delays on this route?
Sunday is statistically the day of the week that experiences the fewest delays on this flight route. Friday has historically seen more delays on average compared to the rest of the week.
Which airline has the best punctuality record on London to Seattle flights?
According to our data, Delta have had the fewest delays on this route over the last 12 months, with about 5% of their flights experiencing any sort of delay.
How many flights depart from London to Seattle on average per day?
23 flights are operational daily from London to Seattle as of October 2026. The most popular departure time for this route is 16:00, with 53% of flights per day taking off in the afternoon.
How many flights depart from London to Seattle on average per week?
As of October 2026, there are 161 flights per week flying from London to Seattle. The most common day of the week flights depart is Mon, with 15% of flights taking off on this day.
When to book flights from London to Seattle
Cheap London to Seattle (LON to SEA) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from London to Seattle
Frequently asked questions about flying from London to Seattle
How far is London to Seattle/Tacoma Intl by plane?
Seattle/Tacoma Intl is 7694.7 km away from London. Flights usually cover this in 12h 45m, depending on flying conditions and air traffic around both airports.
When did momondo last update prices for flights from London to Seattle/Tacoma Intl Airport?
Prices for flights from London to Seattle/Tacoma Intl Airport were last updated today.
How old do you have to be to fly from London to Seattle/Tacoma Intl Airport?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and stopovers. It is recommended that you verify with the airline you are booking with for travel from London to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The travel and health documents you'll need for your trip to Seattle/Tacoma Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's licence and a passport that is valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from London to Seattle?
momondo data reveals that the most frequently booked plane model on the route from London to Seattle is Boeing 787-9 Dreamliner, representing 24.77% of all bookings. The subsequent popular models are Boeing 787-10 Dreamliner at 20.49%, Airbus A330-900neo at 14.31%, and Boeing 777-300ER at 13.69%.
Travelling to a place near Seattle?
Book flights to Seattle if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from London to Seattle?
We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from London to Seattle for you.
Can I find flights from London to Seattle with flexible booking policies on momondo?
Flights from London to Seattle with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.
How can momondo help me find flights from London to Seattle?
momondo provides multiple filters to help you find the best flight to Seattle from London. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.
I’m not ready to book a flight from London to Seattle right now. Can momondo alert me if prices change?
If you are not ready to book a flight from London to Seattle now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Seattle and let you know when they change.