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Not ready to book? to track prices.Find the cheapest flights from London Heathrow Airport to Seattle
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Delta flights from London Heathrow Airport to Seattle
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British Airways flights from London Heathrow Airport to Seattle
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How to get the cheapest flight ticket from London Heathrow Airport 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 cheapest month to fly to Seattle?
If you aren’t able to travel to Seattle during the month of February, then flying in November is also cheap. Prices for this month can be found on momondo for an average of C$ 951.
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 Heathrow Airport 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 Heathrow to Seattle/Tacoma Intl flight route?
Fly from London Heathrow to Seattle/Tacoma Intl for the best London Heathrow - 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 Heathrow Airport 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 Heathrow Airport for as low as C$ 970 on momondo.
What cabin class options are available on London Heathrow to Seattle/Tacoma Intl flights?
There are 2 cabin classes available to choose from on London Heathrow 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 Heathrow Airport to Seattle on average per day?
The number of flights available between London Heathrow Airport and Seattle is 19 per day as of April 2025. The most frequent departure time is 4:00p.m., with 68% of daily flights leaving in the afternoon.
How many flights depart from London Heathrow Airport to Seattle on average per week?
The number of flights available between London Heathrow Airport and Seattle is 137 per week as of April 2025. The most frequent departure day is Mon, with 16% of weekly flights leaving on this day.
When to book flights from London Heathrow Airport to Seattle
Cheap London Heathrow Airport to Seattle (LHR to SEA) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from London Heathrow Airport to Seattle
How far is London Heathrow to Seattle/Tacoma Intl by plane?
London Heathrow and Seattle/Tacoma Intl are 7683.2 km apart from one another. By plane, this route typically takes 9h 45m.
When did momondo last update prices for flights from London Heathrow Airport to Seattle/Tacoma Intl Airport?
Prices for flights from London Heathrow Airport to Seattle/Tacoma Intl Airport are updated daily.
How old do you have to be to fly from London Heathrow Airport to Seattle/Tacoma Intl Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from London Heathrow Airport to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The necessary travel and health documents for your Seattle/Tacoma Intl Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from London Heathrow Airport to Seattle?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from London Heathrow Airport to Seattle is Boeing 787-10 Dreamliner (28.22% of total bookings). The next most popular plane models are Airbus A330-900neo (24.33%), Boeing 777-300ER (15.31%), and Boeing 787-9 Dreamliner (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. All flights to Seattle from London on momondo can be compared and filtered by various policies on offer, including flexible booking.
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 offers price alerts on flights to Seattle from London. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.