Cheap flights from London Heathrow Airport to Seattle from $376
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from London Heathrow Airport to Seattle departing on 5/29. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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KLM flights from London Heathrow Airport to Seattle
Our best KLM deals on London Heathrow Airport to Seattle flight tickets
British Airways flights from London Heathrow Airport to Seattle
Our best British Airways deals on London Heathrow Airport to Seattle flight tickets
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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?
In general, February is the cheapest month to fly from London Heathrow Airport to Seattle. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $649. If you don’t want to visit Seattle in February, then you should wait until November to fly from London Heathrow Airport, when ticket prices are also cheap, with an average price of $688.
What is the cheapest day to depart on your flight to Seattle?
On average, the least expensive day to fly to Seattle from London Heathrow Airport is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as $803. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Friday is the most expensive day to depart from London Heathrow Airport because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $1,076.
What is the cheapest time of day to depart on your flight to Seattle?
Flying to Seattle from London Heathrow Airport at noon is the least expensive time of day to depart. momondo users have found prices as low as $841 when looking at flights departing at noon. Flights to Seattle are more costly in the morning, with an average ticket price of $923. Departure times in the morning fall within the peak daily travel times, which is why tickets can be more expensive.
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 $784 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 $702 on momondo.
What cabin class options are available on London Heathrow to Seattle/Tacoma Intl flights?
There are 4 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.
What is the cheapest airline that flies from London Heathrow to Seattle/Tacoma Intl?
Aer Lingus, Virgin Atlantic, and WestJet are the most popular carriers operating from London Heathrow to Seattle/Tacoma Intl
What airlines fly to Seattle?
Delta, British Airways and Virgin Atlantic are the top three most popular airlines that fly to Seattle from London Heathrow Airport according to our data. Delta is the first choice among our users, with 39% of people opting to fly with this airline when traveling to Seattle. Keep in mind that there are 7 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.
How many flights depart from London Heathrow Airport to Seattle on average per day?
As of April 2025, 19 flights take off from London Heathrow Airport and land in Seattle each day. The most common flight departure time for this route is 4:00PM, with 68% of daily flights taking off in the afternoon.
How many flights depart from London Heathrow Airport to Seattle on average per week?
137 flights are operational weekly from London Heathrow Airport 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 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 4774.1 mi apart from one another. Flights usually cover this in 9h 45m, depending on flying conditions and air traffic around both airports.
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 many operators does momondo search for flights from London Heathrow Airport to Seattle/Tacoma Intl Airport?
The number of operators available for flights from London Heathrow Airport to Seattle/Tacoma Intl Airport is 7 as of April 2025.
How old do you have to be to fly from London Heathrow Airport to Seattle/Tacoma Intl Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for 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 flights between London Heathrow Airport 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%.
What is the most popular airline from London Heathrow Airport to Seattle?
Based on momondo bookings for flights between London Heathrow Airport and Seattle, the leading airline is Delta, making up 32% of the total bookings. Other popular airlines include British Airways with 25%, Virgin Atlantic with 15%, and American Airlines with 10%.
Best airlines flying from London Heathrow Airport to Seattle
Compare and see reviews for airlines that fly from London Heathrow Airport to Seattle with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $449 | Free Cancellation | Rating 7.0 487 reviews | |||
| PriceFrom $560 | Free Cancellation | Rating 6.6 6,837 reviews | |||
| PriceFrom $620 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $635 | Free Cancellation | Rating 7.4 643 reviews | |||
| PriceFrom $673 | Free Cancellation | Rating 7.0 2,700 reviews | |||
| PriceFrom $674 | Free Cancellation | Rating 7.8 1,334 reviews | |||
| PriceFrom $675 | Free Cancellation | Rating 8.0 7,936 reviews |
Delta Flights From London Heathrow Airport to Seattle
Delta flies from London Heathrow Airport to Seattle around 12 times per week, with 7,934 momondo users rating the airline 8.0/10. The cheapest Delta deal from London Heathrow Airport to Seattle in the last 72 hours was $675 (round-trip), much lower than the average airfare cost of $871 for Delta flights on this route.
KLM Flights From London Heathrow Airport to Seattle
KLM (7.8/10 from 1,334 reviews) operates around 12 flights from London Heathrow Airport to Seattle in any given week. The average KLM airfare for this route is around $844, with deals from around $674 rare but found on momondo. Referenced prices are for round-trip London Heathrow Airport to Seattle flight searches in the last 72 hours.
Traveling 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?
It is quick and easy to find London to Seattle flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to Seattle that suits you.
Can I find flights from London to Seattle with flexible booking policies on momondo?
Yes. momondo allows you to filter the results for London to Seattle flights to just show those with flexible booking policies.
How can momondo help me find flights from London to Seattle?
Once you have performed a search for London to Seattle flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.
I’m not ready to book a flight from London to Seattle right now. Can momondo alert me if prices change?
Price alerts on flights to Seattle from London are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.