Cheap flights from London Heathrow to Seattle / Tacoma International

Compare London Heathrow to Seattle / Tacoma International flight deals

Find the cheapest month or even day of the year to fly to Seattle / Tacoma International

Book the best Seattle / Tacoma International fare with no extra fees

Flight deals from London Heathrow to Seattle / Tacoma International

Looking for a cheap last-minute deal or the best round-trip flight from London Heathrow Airport to Seattle / Tacoma International Airport? If you want to travel next month, round-trip fares start from $700. Find the lowest prices on one-way and round-trip tickets right here.

Seattle.$619 per passenger.Departing Mon, Sep 14, returning Thu, Oct 8.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Mon, Sep 14, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Thu, Oct 8, arriving in London Heathrow.Price includes taxes and charges.From $619, select.

Seattle.$652 per passenger.Departing Thu, Jan 14, returning Thu, Jan 21.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Thu, Jan 14, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Thu, Jan 21, arriving in London Heathrow.Price includes taxes and charges.From $652, select.

Seattle.$652 per passenger.Departing Wed, Nov 4, returning Tue, Dec 8.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Wed, Nov 4, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Tue, Dec 8, arriving in London Heathrow.Price includes taxes and charges.From $652, select.

Seattle.$652 per passenger.Departing Thu, Dec 10, returning Mon, Dec 14.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Thu, Dec 10, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Mon, Dec 14, arriving in London Heathrow.Price includes taxes and charges.From $652, select.

Seattle.$652 per passenger.Departing Tue, Feb 2, returning Tue, Feb 16.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Tue, Feb 2, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Tue, Feb 16, arriving in London Heathrow.Price includes taxes and charges.From $652, select.

Seattle.$652 per passenger.Departing Fri, Oct 2, returning Mon, Oct 19.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Fri, Oct 2, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Mon, Oct 19, arriving in London Heathrow.Price includes taxes and charges.From $652, select.

Seattle.$652 per passenger.Departing Thu, Nov 5, returning Tue, Nov 10.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Thu, Nov 5, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Tue, Nov 10, arriving in London Heathrow.Price includes taxes and charges.From $652, select.

Seattle.$653 per passenger.Departing Wed, Feb 17, returning Mon, Mar 1.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Wed, Feb 17, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Mon, Mar 1, arriving in London Heathrow.Price includes taxes and charges.From $653, select.

Seattle.$653 per passenger.Departing Mon, Jan 18, returning Sun, Feb 7.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Mon, Jan 18, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Sun, Feb 7, arriving in London Heathrow.Price includes taxes and charges.From $653, select.

Seattle.$653 per passenger.Departing Thu, Mar 4, returning Thu, Mar 18.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Thu, Mar 4, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Thu, Mar 18, arriving in London Heathrow.Price includes taxes and charges.From $653, select.

Seattle.$655 per passenger.Departing Tue, Dec 1, returning Sat, Jan 30.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Tue, Dec 1, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Sat, Jan 30, arriving in London Heathrow.Price includes taxes and charges.From $655, select.

Seattle.$660 per passenger.Departing Fri, Sep 4, returning Wed, Sep 30.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Fri, Sep 4, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Wed, Sep 30, arriving in London Heathrow.Price includes taxes and charges.From $660, select.

Seattle.$661 per passenger.Departing Mon, Sep 28, returning Tue, Dec 1.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Mon, Sep 28, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Tue, Dec 1, arriving in London Heathrow.Price includes taxes and charges.From $661, select.

Seattle.$661 per passenger.Departing Mon, Sep 28, returning Mon, Nov 30.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Mon, Sep 28, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Mon, Nov 30, arriving in London Heathrow.Price includes taxes and charges.From $661, select.

Seattle.$667 per passenger.Departing Mon, Aug 31, returning Tue, Sep 8.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Mon, Aug 31, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Tue, Sep 8, arriving in London Heathrow.Price includes taxes and charges.From $667, select.

Seattle.$674 per passenger.Departing Mon, Oct 5, returning Mon, Nov 2.Round-trip flight with Icelandair.Outbound indirect flight with Icelandair, departing from London Heathrow on Mon, Oct 5, arriving in Seattle / Tacoma International.Inbound indirect flight with Icelandair, departing from Seattle / Tacoma International on Mon, Nov 2, arriving in London Heathrow.Price includes taxes and charges.From $674, select.

Find the cheapest month to fly from London Heathrow to Seattle / Tacoma International

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like London Heathrow to Seattle / Tacoma International flights are currently cheapest in October.

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Direct flights from London Heathrow to Seattle / Tacoma International

London Heathrow to Seattle / Tacoma International: Alternative routes

Compare routes from London Heathrow to Seattle below. You may find an airport to fly into that's cheaper, faster, or easier than Seattle / Tacoma International.

London to Seattle: Flight information

The things to know before you go.

Cheapest flight found	$619
Cheapest month to fly	September
Average flight time	10 hrs, 14 mins
Most popular airline	KLM
Average flights per week	155

Finding cheap flights from London Heathrow to Seattle / Tacoma International: Frequently asked questions

How much are round-trip flights from London Heathrow to Seattle / Tacoma International?

The best price we found for a round-trip flight from London Heathrow to Seattle / Tacoma International is $619. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.

How long does it take to fly from London Heathrow to Seattle / Tacoma International?

10 hours and 14 minutes is the average flight time from London Heathrow to Seattle / Tacoma International.

Which airlines fly direct from London Heathrow to Seattle / Tacoma International?

KLM, Alaska Airlines and Virgin Atlantic fly direct from London Heathrow to Seattle / Tacoma International.

How many flights are there a week from London Heathrow to Seattle / Tacoma International?

There are 155 flights per week flying from London Heathrow to Seattle / Tacoma International, as of May 2026.

When is the cheapest time to fly from London Heathrow to Seattle / Tacoma International?

The cheapest month to fly from London Heathrow to Seattle / Tacoma International is usually September.

Which upcoming date is cheapest to fly from London Heathrow Airport to Seattle / Tacoma International Airport on?

After crunching the numbers on our flight calendar, we found that it's currently cheapest to fly from London Heathrow Airport to Seattle / Tacoma International Airport on Monday, September 14, 2026.

Can I get a direct flight from London Heathrow Airport to Seattle / Tacoma International Airport?

Yes – the average flight time is 10 hours and 14 minutes.

How can I find the best flight deal to Seattle / Tacoma International?

We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to Seattle / Tacoma International but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.

When is the best time to book flights to Seattle?

We crunched all the numbers in our flight calendar, and it looks like the cheapest time to book a flight to Seattle is around 40 days in advance, so don’t leave your flight to the last minute.

Which is the cheapest airline to fly with from London Heathrow Airport to Seattle / Tacoma International?

Currently, Icelandair and Finnair offer the cheapest flight tickets to Seattle / Tacoma International.

Flying from London Heathrow Airport (LHR) to Seattle-Tacoma International Airport (SEA): what you need to know

Take a direct flight from London Heathrow Airport to Seattle-Tacoma International Airport and you'll be in the air for an average of 10 hours 5 minutes.
Seattle is seven hours behind London and observes the UTC-7 timezone.
Every week, there are 38 London Heathrow Airport to Seattle-Tacoma International Airport flights. If you prefer to take off as early as possible, select the 09:25 British Airways flight. If you'd rather make the most of your day before you fly, the latest flight is at 16:50 with Delta Air Lines.
Give yourself plenty of time to catch your LHR to SEA flight. As a rule of thumb, arrive two hours before international departures and an hour ahead for domestic flights.
During popular months like July, it's a good idea to get to the airport well in advance. Arrive two hours before a domestic departure and four hours ahead of an international flight whenever you're traveling during a peak period in general.
You can fly nonstop to Seattle, United States. Take off with one of these airlines that operate direct flights from London Heathrow Airport to Seattle-Tacoma International Airport:
The airline with the highest booking volume on this route is British Airways.
The most punctual carrier that offers LHR to SEA flights is Delta Air Lines. Its services arrive as scheduled 71.43% of the time.
Think about adding a stopover when booking your ticket from London Heathrow Airport to Seattle-Tacoma International Airport. Just deselect 'Direct flights only' to break up your trip, or maybe even explore a new city along the way. Here's where you can stop between LHR and SEA:
- Vancouver International Airport
- Keflavik International Airport
- Charles de Gaulle Airport

How to find the cheapest flights from London Heathrow Airport (LHR) to Seattle-Tacoma International Airport (SEA)

At the moment, $395 is the cheapest price we've seen for a one-way London Heathrow Airport to Seattle-Tacoma International Airport flight. The best price for a return ticket is $619. Keep in mind that fares can change due to demand at the time of booking.
Score cheap tickets from LHR to SEA by booking six months ahead. Based on our research, that's the sweet spot for finding the biggest deals.
The cheapest month for flights from London Heathrow Airport to Seattle-Tacoma International Airport is May. Use the 'Whole month' tool to find the lowest airfares if you have flexible travel dates.
You won't have to check every day to find out if fares have gone down when you set up a Price Alert. We'll update you as soon as there's a better deal on cheap flights from LHR to SEA.
Pick your preferred arrival and departure times, number of stops and airlines with the filters. Or sort your results by 'Cheapest' to see the best deals on flights from London Heathrow Airport to Seattle-Tacoma International Airport.

Handy information about London Heathrow Airport (LHR)

Of all flights leaving London Heathrow Airport, 68.18% arrive as scheduled at their destination.
Central London to London Heathrow Airport is approximately 31 kilometers. Depending on traffic, it'll take about 55 minutes to get there if you're driving, catching a cab or ride-sharing.
The trip when using public transport typically takes 1 hour.
Taking an early flight from London Heathrow Airport to Seattle-Tacoma International Airport? Avoid the stress of rushing to the airport (and enjoy a little extra shut-eye) by picking one of these stays near LHR:

Arriving at Seattle-Tacoma International Airport (SEA)

Consider booking a hotel close to SEA if you're catching a late London Heathrow Airport to Seattle-Tacoma International Airport flight. Check in to one of these options and make your arrival easier:
Pick up a Seattle-Tacoma International Airport rental car and explore Seattle and beyond with your own wheels. Thrifty, Europcar and Budget are top outlets you can book with here.
Reserving your vehicle from Seattle-Tacoma International Airport around one week ahead can help you get the lowest rate.

Getting from Seattle-Tacoma International Airport (SEA) to central Seattle

Seattle-Tacoma International Airport to central Seattle has a drive time of about 20 minutes. It's approximately 23 kilometers away.
It typically takes 55 minutes when traveling by public transport.

When to fly to Seattle-Tacoma International Airport (SEA)

July is the most popular month for flights from London Heathrow Airport to Seattle-Tacoma International Airport. For a quieter experience, travel to Seattle in May.
Book your flight from London Heathrow Airport to Seattle-Tacoma International Airport for August if you want to explore Seattle during its warmest month. You can expect temperatures of between 12ºC (54ºF) and 28ºC (82ºF).
If you like traveling in cooler conditions, search for a cheap ticket from LHR to SEA in February. Average temperatures are between -1ºC (30ºF) and 11ºC (52ºF) then.

Explore more of United States

Portland is just one of the many cities in United States waiting to be discovered once you've seen the sights of Seattle. Around 241 kilometers away to the south, check out popular attractions including Pioneer Courthouse Square, Portland Japanese Garden and Pittock Mansion.
Spokane is another standout destination in United States and is around 370 kilometers east of Seattle. No journey is complete without visiting Manito Park, Northwest Museum of Arts & Culture and Spokane Falls.