Cheap flights from London Heathrow Airport to Seattle from £238
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 21/9. 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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Scandinavian Airlines flights from London Heathrow Airport to Seattle
Our best Scandinavian Airlines deals on London Heathrow Airport to Seattle flight tickets
KLM flights from London Heathrow Airport to Seattle
Our best KLM 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 typical price of a round-trip flight between London Heathrow Airport and Seattle?
What is the cheapest month to fly to Seattle?
The cheapest month to fly to Seattle from London Heathrow Airport is in February. Flight prices, which tend to average around £482, are often lower during this time because this is during the off-season. The month of November is another great option to travel to Seattle, with average flight prices from London Heathrow Airport averaging around £506.
What is the cheapest day to depart on your flight to Seattle?
According to our data, Tuesday is the cheapest day to fly to Seattle from London Heathrow Airport. The lowest ticket price found for a Tuesday departure recently was £600. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. Be sure to avoid booking your departure on a Sunday as prices are generally higher than usual. According to our data, the average ticket price to Seattle on Sunday is £731.
What is the cheapest time of day to depart on your flight to Seattle?
According to our data, the cheapest time of day to fly to Seattle is in the evening. momondo users have found flights departing from London Heathrow Airport to Seattle in the evening for as low as £519. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the morning are often more expensive, with an average ticket price of £648.
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 £575 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 £514 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.
Can stopping save me money on London Heathrow Airport to Seattle flights?
No. A direct flight is the cheapest option for a flight between London Heathrow Airport to Seattle.
How have London Heathrow Airport to Seattle flight prices changed over time?
As of June 2025, prices for London Heathrow Airport to Seattle flights are approximately 10% more expensive when compared to flights at the same time last year.
What is the cheapest airline that flies from London Heathrow to Seattle/Tacoma Intl?
Aer Lingus, Scandinavian Airlines, and British Airways are the most popular carriers operating from London Heathrow to Seattle/Tacoma Intl
Which airlines fly to Seattle?
Virgin Atlantic, British Airways and KLM are the top three most popular airlines that fly to Seattle from London Heathrow Airport according to our data. Virgin Atlantic is the first choice among our users, with 54% of people opting to fly with this airline when travelling to Seattle. Keep in mind that there are 13 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 June 2025, 18 flights take off from London Heathrow Airport and land in Seattle each day. The most common flight departure time for this route is 16:00, with 68% of daily flights taking off in the afternoon.
How many flights depart from London Heathrow Airport to Seattle on average per week?
132 flights are operational weekly from London Heathrow Airport to Seattle as of June 2025. The most popular departure day for this route is Mon, with 17% 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?
The distance between London Heathrow and Seattle/Tacoma Intl is about 4774.1 mi. A reasonable flight in good conditions will take 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 were last updated today.
How many operators does momondo search for flights from London Heathrow Airport to Seattle/Tacoma Intl Airport?
As of June 2025, there are 13 operators available to choose from for flights from London Heathrow Airport to Seattle/Tacoma Intl Airport.
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 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 Heathrow Airport to Seattle?
momondo data reveals that the most frequently booked plane model on the route from London Heathrow Airport to Seattle is Airbus A330-900neo, representing 25.99% of all bookings. The subsequent popular models are Boeing 787-10 Dreamliner at 25.43%, Boeing 777-300ER at 16.36%, and Boeing 787-9 Dreamliner at 10.01%.
What is the most popular airline from London Heathrow Airport to Seattle?
momondo data reveals that the most frequently booked airline on the route from London Heathrow Airport to Seattle is Virgin Atlantic, representing 44% of all bookings. The subsequent popular airlines are British Airways at 20%, KLM at 10%, and Icelandair at 7%.
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 £7 | Free Cancellation | Rating 7.1 1,118 reviews | |||
| PriceFrom £352 | Free Cancellation | Rating 7.0 499 reviews | |||
| PriceFrom £380 | Free Cancellation | Rating 7.5 1,463 reviews | |||
| PriceFrom £387 | Free Cancellation | Rating 6.7 7,136 reviews | |||
| PriceFrom £394 | Free Cancellation | Rating 7.4 8,790 reviews | |||
| PriceFrom £400 | Free Cancellation | Rating 7.6 1,290 reviews | |||
| PriceFrom £401 | Free Cancellation | Rating 7.8 1,358 reviews | |||
| PriceFrom £416 | Free Cancellation | Rating 7.1 9,531 reviews | |||
| PriceFrom £421 | Free Cancellation | Rating 6.6 7,011 reviews | |||
| PriceFrom £439 | Free Cancellation | Rating 8.0 7,950 reviews |
Delta Flights From London Heathrow Airport to Seattle
Delta operates around 12 flights from London Heathrow Airport to Seattle every week. The average price of these flights found in the last 72 hours has been £859, but momondo users have found Delta deals from London Heathrow Airport to Seattle from as low as £597 round-trip. Delta has been scored 8.0/10 in 7,950 reviews.
KLM Flights From London Heathrow Airport to Seattle
KLM (7.8/10 from 1,358 reviews) operates around 12 flights from London Heathrow Airport to Seattle in any given week. The average KLM airfare for this route is around £771, with deals from around £545 rare but found on momondo. Referenced prices are for round-trip London Heathrow Airport to Seattle flight searches in the last 72 hours.
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Why should I use momondo to find a flight deal from London to Seattle?
Finding the right flight to Seattle from London is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to Seattle quick and easy, saving you time and money.
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?
Once all potential London to Seattle flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.
I’m not ready to book a flight from London to Seattle right now. Can momondo alert me if prices change?
Of course. momondo tracks the price of London to Seattle flights. All you need is a valid email address and we will do the rest; it is that quick and easy.