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Delta flights from London to Seattle
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British Airways flights from London to Seattle
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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?
What is the cheapest month to fly to Seattle?
If you aren’t able to travel to Seattle during the month of January, then flying in March is also cheap. Prices for this month can be found on momondo for an average of C$ 907.
What is the cheapest day to depart on your flight to Seattle?
Our data shows that Friday is the least expensive day to fly to Seattle. Tickets to fly out on this day can be as low as C$ 1,207. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around C$ 3,016. These prices are subject to change though, so be sure to set up a Price Alert for flights to Seattle.
What is the cheapest time of day to depart on your flight to Seattle?
Our most recent data shows that the best time of day to fly to Seattle is in the afternoon. Flights from London to Seattle during this time can be as low as C$ 1,398. Flights in the morning are often more expensive with an average ticket price of C$ 1,586.
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 to Seattle?
You are more likely to see cheaper flights to Seattle from London when booking 24 weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around C$ 1,084 when searching 24 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from London for as low as C$ 970 on momondo.
What cabin class options are available on London to Seattle/Tacoma Intl flights?
There are 2 cabin classes available to choose from on London to Seattle/Tacoma Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
How many flights depart from London to Seattle on average per day?
As of April 2025, 19 flights take off from London and land in Seattle each day. The most common flight departure time for this route is 4:00p.m., with 68% of daily flights taking off in the afternoon.
How many flights depart from London to Seattle on average per week?
137 flights are operational weekly from London to Seattle as of April 2025. The most popular departure day for this route is Mon, with 16% of flights per week 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
How far is London to Seattle/Tacoma Intl by plane?
The straight-line distance from London to Seattle/Tacoma Intl is 7694.7 km. In terms of flight time, this usually takes a little over 9h 45m.
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 refresh daily.
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 layovers. 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 required for your trip to Seattle/Tacoma Intl Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Seattle/Tacoma Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from London to Seattle?
Based on momondo bookings for flights between London and Seattle, the leading plane model is Boeing 787-10 Dreamliner, making up 28.22% of the total bookings. Other popular models include Airbus A330-900neo with 24.33%, Boeing 777-300ER with 15.31%, and Boeing 787-9 Dreamliner with 13.98%.
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?
momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from London to Seattle . Millions of users trust and use momondo every year so you are in good hands.
Can I find flights from London to Seattle with flexible booking policies on momondo?
Yes. momondo enables you to select and highlight flights to Seattle from London with this policy.
How can momondo help me find flights from London to Seattle?
Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Seattle from London.
I’m not ready to book a flight from London to Seattle right now. Can momondo alert me if prices change?
Yes. momondo can track prices for London to Seattle flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.