What are the cheapest airlines flying from London Heathrow Airport to Seattle round-trip?

According to our current data, Icelandair (£449), Lufthansa (£455), and American Airlines (£461) offers the cheapest pricing from London Heathrow Airport to Seattle. Icelandair is priced at 25% lower than the current average price of a flight leaving 3 months from now.

What are the cheapest airlines to fly from London Heathrow Airport to Seattle one-way?

The cheapest airline one-way is WestJet, with whom users have recently found tickets for as low as £393. However, be on the lookout for offers from Aer Lingus and Icelandair, as they are both options that can get you from London Heathrow Airport to Seattle for a low price.

What are the cheapest flights from London Heathrow Airport to Seattle?

The cheapest flight price from London Heathrow Airport to Seattle is £478. On average you can expect to pay £2,075. The most popular route, (London Heathrow - Seattle/Tacoma Intl), can usually be booked for £388.

What are the most reliable airlines from London Heathrow Airport to Seattle?

Consider Aeromexico (98%), Singapore Airlines (98%) or KLM (92%) when booking your flight. These represent the most reliable airlines when flying from London Heathrow Airport to Seattle.

What are the most popular airlines that fly from London Heathrow Airport to Seattle?

When booking a flight from London Heathrow Airport to Seattle, you may want to consider flying on Air Canada, Air France or Finnair as they are the most popular for this route.

What is the cheapest day to fly round-trip from London Heathrow Airport to Seattle?

Users have found that flying from London Heathrow Airport to Seattle on a Saturday typically leans towards higher prices. However, this doesn’t mean you still can’t find a deal. Flexibility with other aspects of your flight can still land a great price for your trip.

How far in advance should I book a flight from London Heathrow Airport to Seattle?

Find a great deal and save up to 37% by booking at least 44 days prior to your desired departure date, rather than waiting until the week of travel. According to our data, there are a number of flights available from London Heathrow Airport to Seattle within the next two weeks, with the cheapest ticket starting at £603.

What is the cheapest month to fly from London Heathrow Airport to Seattle?

Due to multiple factors, expect to potentially pay more when booking in August. For low rates, January can be a great choice for travel to Seattle. Flights to Seattle from London Heathrow Airport in January are about £594 on average during January, but can be found for as low as £337.

What airport do you fly into for flights to Seattle from London Heathrow?

If you book a flight to Seattle from London Heathrow, you will be flying to Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 11 flights from London Heathrow to Seattle/Tacoma Intl per day from 12 different airlines.

Can I find deals for flights from Heathrow to Seattle that include hotel bookings?

Yes. In addition to deals on Heathrow to Seattle flights, Cheapflights offers holiday packages that include both flights and hotel.

How can I find direct flights from Heathrow to Seattle?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Heathrow to Seattle.

Can I find deals for business class flights from Heathrow to Seattle?

Yes. Cheapflights offers flight deals from Heathrow to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

£393+ Flights from London Heathrow Airport to Seattle

Cheapflights Tip: The best prices from London Heathrow to Seattle/Tacoma Intl are usually found in February or November, booked 54 days in advance, depart on a Tuesday or Wednesday and return on a Monday

Cheap flight deals from Heathrow to Seattle

Round-trip from	£449
One-way from	£393
Popular in	July
Cheapest in	February
Average price	£579
Good round-trip deal	£561 or less
Good one-way deal	£598 or less

Icelandair
1/9-29/9
2 total stops
45h 40m total
London to Seattle

Search Deals

WestJet
28/4
1 total stop
31h 03m total
London to Seattle

Search Deals

Highest demand for flights based on searches. 15% potential increase in price (£85 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 2% potential price decrease (£12 potential savings vs. average return price).

Search Deals

Average for round-trip flights in March 2025

Search Deals

Price to beat on a round-trip flight from London Heathrow to Seattle/Tacoma Intl.

Search Deals

Price to beat on a one-way flight from London Heathrow to Seattle/Tacoma Intl.

Search Deals

Find flight deals from Heathrow to Seattle

Cheapest flights from Heathrow to Seattle
Explore the most affordable flight options available from Heathrow to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 20 March 2025.

Mon 1/913:05LHR - SEA

1 stop12h 45mIcelandair

Mon 29/919:00SEA - LHR

1 stop32h 55mIcelandair

Deal found 19/3£449

Mon 15/908:40LHR - SEA

1 stop14h 15mMultiple Airlines

Wed 24/908:00SEA - LHR

1 stop14h 55mMultiple Airlines

Deal found 19/3£454

Fri 2/506:30LHR - SEA

1 stop13h 55mLufthansa

Sun 11/508:10SEA - LHR

1 stop14h 45mLufthansa

Deal found 19/3£455

Mon 5/510:20LHR - SEA

1 stop13h 40mAmerican Airlines

Sun 11/517:40SEA - LHR

1 stop13h 30mAmerican Airlines

Deal found 20/3£461

Wed 14/508:40LHR - SEA

2 stops18h 57mAir Canada

Sun 18/505:40SEA - LHR

2 stops16h 50mAir Canada

Deal found 19/3£462

Wed 23/409:00LHR - SEA

1 stop15h 59mUnited Airlines

Tue 29/409:10SEA - LHR

2 stops18h 00mUnited Airlines

Deal found 19/3£466

Wed 23/406:00LHR - SEA

2 stops24h 43mSWISS

Tue 29/415:24SEA - LHR

2 stops18h 26mSWISS

Deal found 19/3£469

Wed 23/406:15LHR - SEA

1 stop13h 00mVirgin Atlantic

Tue 29/417:35SEA - LHR

Nonstop9h 45mVirgin Atlantic

Deal found 19/3£470

Sun 11/520:55LHR - SEA

1 stop22h 45mKLM

Tue 20/520:20SEA - LHR

Nonstop9h 55mKLM

Deal found 19/3£471

Mon 21/417:25LHR - SEA

Nonstop10h 20mAir France

Tue 29/420:20SEA - LHR

Nonstop9h 55mAir France

Deal found 19/3£475

Sun 14/911:45LHR - SEA

1 stop32h 00mDelta

Tue 23/917:35SEA - LHR

Nonstop9h 45mDelta

Deal found 19/3£489

Tue 6/509:25LHR - SEA

Nonstop9h 45mBritish Airways

Tue 13/513:30SEA - LHR

Nonstop9h 20mBritish Airways

Deal found 19/3£499

Best flights from Heathrow to Seattle
Discover carefully curated flight deals from Heathrow to Seattle that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 20 March 2025.

Mon 1/913:05LHR - SEA

1 stop12h 45mIcelandair

Mon 29/919:00SEA - LHR

1 stop32h 55mIcelandair

Deal found 19/3£449

Mon 15/908:40LHR - SEA

1 stop14h 15mMultiple Airlines

Wed 24/908:00SEA - LHR

1 stop14h 55mMultiple Airlines

Deal found 19/3£454

Fri 2/506:30LHR - SEA

1 stop13h 55mLufthansa

Sun 11/508:10SEA - LHR

1 stop14h 45mLufthansa

Deal found 19/3£455

Mon 5/510:20LHR - SEA

1 stop13h 40mAmerican Airlines

Sun 11/517:40SEA - LHR

1 stop13h 30mAmerican Airlines

Deal found 20/3£461

Wed 14/508:40LHR - SEA

2 stops18h 57mAir Canada

Sun 18/507:20SEA - LHR

1 stop15h 10mAir Canada

Deal found 19/3£462

Wed 23/409:00LHR - SEA

1 stop15h 59mUnited Airlines

Tue 29/409:10SEA - LHR

2 stops18h 00mUnited Airlines

Deal found 19/3£466

Wed 23/406:00LHR - SEA

2 stops24h 43mSWISS

Tue 29/415:24SEA - LHR

2 stops18h 26mSWISS

Deal found 19/3£469

Wed 23/406:15LHR - SEA

1 stop13h 00mVirgin Atlantic

Tue 29/417:35SEA - LHR

Nonstop9h 45mVirgin Atlantic

Deal found 19/3£470

Sun 11/520:55LHR - SEA

1 stop22h 45mKLM

Tue 20/520:20SEA - LHR

Nonstop9h 55mKLM

Deal found 19/3£471

Mon 21/417:25LHR - SEA

Nonstop10h 20mAir France

Tue 29/420:20SEA - LHR

Nonstop9h 55mAir France

Deal found 19/3£475

Sun 14/911:45LHR - SEA

1 stop32h 00mDelta

Tue 23/917:35SEA - LHR

Nonstop9h 45mDelta

Deal found 19/3£489

Tue 6/509:25LHR - SEA

Nonstop9h 45mBritish Airways

Tue 13/513:30SEA - LHR

Nonstop9h 20mBritish Airways

Deal found 19/3£499

Direct flights from Heathrow to Seattle
Explore direct flight options from Heathrow to Seattle based on user searches, and compare prices and availability for your desired travel dates. Data last updated 20 March 2025.

Mon 21/417:25LHR - SEA

Nonstop10h 20mKLM

Tue 29/420:20SEA - LHR

Nonstop9h 55mKLM

Deal found 20/3£474

Mon 21/417:25LHR - SEA

Nonstop10h 20mAir France

Tue 29/420:20SEA - LHR

Nonstop9h 55mAir France

Deal found 19/3£475

Wed 23/413:25LHR - SEA

Nonstop10h 20mVirgin Atlantic

Tue 29/420:20SEA - LHR

Nonstop9h 55mVirgin Atlantic

Deal found 19/3£476

Mon 21/417:25LHR - SEA

Nonstop10h 20mMultiple Airlines

Tue 6/520:20SEA - LHR

Nonstop9h 55mMultiple Airlines

Deal found 20/3£489

Tue 22/409:25LHR - SEA

Nonstop9h 45mIberia

Wed 30/413:30SEA - LHR

Nonstop9h 20mIberia

Deal found 19/3£492

Tue 6/509:25LHR - SEA

Nonstop9h 45mBritish Airways

Tue 13/513:30SEA - LHR

Nonstop9h 20mBritish Airways

Deal found 19/3£499

Mon 21/417:25LHR - SEA

Nonstop10h 20mDelta

Tue 6/517:35SEA - LHR

Nonstop9h 45mDelta

Deal found 19/3£499

Tue 25/309:25LHR - SEA

Nonstop9h 55mAmerican Airlines

Tue 1/413:30SEA - LHR

Nonstop9h 20mAmerican Airlines

Deal found 18/3£504

Tue 1/409:25LHR - SEA

Nonstop9h 45mFinnair

Tue 8/420:20SEA - LHR

Nonstop9h 20mFinnair

Deal found 18/3£535

Last-minute flights from Heathrow to Seattle
Discover last-minute flight deals from Heathrow to Seattle. Data last updated 20 March 2025 and is based on user searches.

Tue 25/309:25LHR - SEA

Nonstop9h 55mAmerican Airlines

Tue 1/413:30SEA - LHR

Nonstop9h 20mAmerican Airlines

Deal found 18/3£504

Wed 26/306:50LHR - SEA

2 stops20h 34mUnited Airlines

Wed 9/412:54SEA - LHR

1 stop12h 46mUnited Airlines

Deal found 19/3£472

Wed 26/306:30LHR - SEA

1 stop13h 10mKLM

Wed 9/420:20SEA - LHR

Nonstop9h 55mKLM

Deal found 19/3£496

Wed 26/313:15LHR - SEA

Nonstop10h 00mDelta

Mon 7/420:20SEA - LHR

Nonstop9h 55mDelta

Deal found 20/3£501

Wed 26/309:25LHR - SEA

1 stop18h 45mFinnair

Wed 16/413:35SEA - LHR

1 stop12h 55mFinnair

Deal found 20/3£546

Wed 26/313:35LHR - SEA

1 stop16h 18mAustrian Airlines

Thu 3/408:15SEA - LHR

1 stop14h 40mAustrian Airlines

Deal found 20/3£629

Thu 27/311:35LHR - SEA

1 stop16h 26mMultiple Airlines

Sat 5/419:05SEA - LHR

1 stop34h 15mMultiple Airlines

Deal found 20/3£484

Thu 27/315:00LHR - SEA

2 stops37h 45mAir Canada

Sat 5/405:45SEA - LHR

1 stop23h 35mAir Canada

Deal found 20/3£489

Thu 27/312:40LHR - SEA

Nonstop10h 00mVirgin Atlantic

Sat 5/407:30SEA - LHR

1 stop19h 00mVirgin Atlantic

Deal found 20/3£530

Sat 29/309:10LHR - SEA

1 stop19h 21mAir France

Fri 25/420:20SEA - LHR

Nonstop9h 55mAir France

Deal found 19/3£648

Sat 29/307:25LHR - SEA

2 stops22h 13mIcelandair

Sat 5/423:55SEA - LHR

2 stops36h 50mIcelandair

Deal found 20/3£702

Sun 30/315:20LHR - SEA

2 stops28h 12mLufthansa

Sat 5/419:33SEA - LHR

1 stop27h 52mLufthansa

Deal found 20/3£680

One-way flights from Heathrow to Seattle
Search for one-way flight options from Heathrow to Seattle. Find affordable one-way fares based on user searches. Data last updated 20 March 2025.

Mon 28/413:55LHR - SEA

1 stop31h 03mWestJet

Deal found 19/3£393

Mon 31/320:50LHR - SEA

3 stops54h 19mMultiple Airlines

Deal found 20/3£406

Mon 28/412:00LHR - SEA

1 stop12h 59mAer Lingus

Deal found 18/3£408

Tue 27/521:25LHR - SEA

1 stop22h 00mIcelandair

Deal found 20/3£424

Wed 23/409:50LHR - SEA

Nonstop9h 45mIberia

Deal found 19/3£497

Mon 28/409:50LHR - SEA

Nonstop9h 45mFinnair

Deal found 19/3£516

Mon 28/409:50LHR - SEA

Nonstop9h 45mBritish Airways

Deal found 20/3£516

Cheapflights Fare Finder

Use the filters below to find and compare flights from London Heathrow Airport to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 22/4

21:25-17:50

1 stop28h 25m

Seattle/Tacoma Intl

Fri 2/5

19:00-20:20

1 stop17h 20m

£450

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 2/5

06:30-12:25

1 stop13h 55m

Seattle/Tacoma Intl

Sun 11/5

08:10-06:55

1 stop14h 45m

£455

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 22/4

06:30-12:25

1 stop13h 55m

Seattle/Tacoma Intl

Fri 2/5

10:00-11:50

2 stops17h 50m

£458

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 5/5

10:20-16:00

1 stop13h 40m

Seattle/Tacoma Intl

Sun 11/5

17:40-15:10

1 stop13h 30m

£461

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 14/5

08:40-19:37

2 stops18h 57m

Seattle/Tacoma Intl

Sun 18/5

07:20-06:30

1 stop15h 10m

£462

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 23/4

09:00-16:59

1 stop15h 59m

Seattle/Tacoma Intl

Tue 29/4

09:10-11:10

2 stops18h 00m

£466

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 23/4

06:00-22:43

2 stops24h 43m

Seattle/Tacoma Intl

Tue 29/4

15:24-17:50

2 stops18h 26m

£469

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 23/4

06:15-11:15

1 stop13h 00m

Seattle/Tacoma Intl

Tue 29/4

17:35-11:20

Nonstop9h 45m

£470

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Sun 11/5

20:55-11:40

1 stop22h 45m

Seattle/Tacoma Intl

Tue 20/5

20:20-14:15

Nonstop9h 55m

£471

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 21/4

17:25-19:45

Nonstop10h 20m

Seattle/Tacoma Intl

Tue 29/4

20:20-14:15

Nonstop9h 55m

£475

Flights are sorted by cheapest return flights first.

Deals found on 19/3

Showing 1-10 of 21 results

Best time to book a flight from Heathrow to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Heathrow with our price prediction graph.

Estimated return price

Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from London Heathrow Airport to Seattle

How far ahead should I book a flight from London Heathrow Airport to Seattle?

The best time to book flights from London Heathrow Airport to Seattle is 54 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from London Heathrow Airport to Seattle?

Currently, January is the cheapest month in which you can book a flight from London Heathrow Airport to Seattle (average of £622). Flying from London Heathrow Airport to Seattle in July is currently the most expensive (average of £946). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from LHR to SEA?

It’s typically best to fly out from London Heathrow Airport to Seattle in the evening. Doing so could potentially save you 23% on the flight price compared to flying in the morning, which is usually more expensive.

What is the cheapest day to fly from London Heathrow Airport to Seattle?

Travellers seeking maximum savings on their London Heathrow Airport to Seattle flight should consider departing on Monday evenings when fares are most often at their lowest. Sunday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from London Heathrow Airport to Seattle

The most flights from LHR to SEA are scheduled on a Wednesday (15 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (6 on average).

Rainfall in Seattle by month

In terms of precipitation, rainfall in Seattle ranges from 18.0 - 168.0 inches per month. November is typically the wettest month, when rainfall can reach 168.0 mm. July is typically the driest time to visit Seattle when rainfall is around 18.0 mm.

Temperature in Seattle by month

If weather is an important factor for your trip to Seattle, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 19.0 C. Travellers hoping to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 5.0 C).

Reviews of airlines servicing Seattle

Get a feel of what it's like to fly with Delta, KLM and Finnair from London to Seattle by reading reviews from past customers. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Delta

8.0

Very Good

7,895 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Delta

8.0

Very Good

7,895 reviews

Delta

8.0

Very Good

7,895 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

KLM

7.8

Good

1,319 reviews

Delta

8.0

Very Good

7,895 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Finnair

7.6

Good

1,266 reviews

Delta

8.0

Very Good

7,895 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

SWISS

7.5

Good

1,567 reviews

Delta

8.0

Very Good

7,895 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Air France

7.4

Good

1,422 reviews

Delta

8.0

Very Good

7,895 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Related info for your journey

What airport do you fly into for flights to Seattle from London Heathrow?
If you book a flight to Seattle from London Heathrow, you will be flying to Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 11 flights from London Heathrow to Seattle/Tacoma Intl per day from 12 different airlines.
What are the cheapest airlines flying from London Heathrow Airport to Seattle round-trip?
According to our current data, Icelandair (£449), Lufthansa (£455), and American Airlines (£461) offers the cheapest pricing from London Heathrow Airport to Seattle. Icelandair is priced at 25% lower than the current average price of a flight leaving 3 months from now.
What are the cheapest airlines to fly from London Heathrow Airport to Seattle one-way?
The cheapest airline one-way is WestJet, with whom users have recently found tickets for as low as £393. However, be on the lookout for offers from Aer Lingus and Icelandair, as they are both options that can get you from London Heathrow Airport to Seattle for a low price.
What are the most reliable airlines from London Heathrow Airport to Seattle?
Consider Aeromexico (98%), Singapore Airlines (98%) or KLM (92%) when booking your flight. These represent the most reliable airlines when flying from London Heathrow Airport to Seattle.
What are the cheapest flights from London Heathrow Airport to Seattle?
The cheapest flight price from London Heathrow Airport to Seattle is £478. On average you can expect to pay £2,075. The most popular route, (London Heathrow - Seattle/Tacoma Intl), can usually be booked for £388.
Can I find deals for flights from Heathrow to Seattle that include hotel bookings?
Yes. In addition to deals on Heathrow to Seattle flights, Cheapflights offers holiday packages that include both flights and hotel.
How can I find direct flights from Heathrow to Seattle?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Heathrow to Seattle.
Can I find deals for business class flights from Heathrow to Seattle?
Yes. Cheapflights offers flight deals from Heathrow to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from London Heathrow Airport to Seattle?
Currently, January is the cheapest month in which you can book a flight from London Heathrow Airport to Seattle (average of £622). Flying from London Heathrow Airport to Seattle in July is currently the most expensive (average of £946). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Tacoma

Leavenworth

Bothell

Browse thousands of different options on Cheapflights for your next trip

Top 10 airlines flying from Heathrow to Seattle

Airline	Cheapest	Average	Flexibility	On-time
Icelandair	Cheapest£385	Average£519	FlexibilityNo cancel fee	On-time76%	Search Icelandair flights
Air France	Cheapest£398	Average£590	FlexibilityNo cancel fee	On-time77%	Search Air France flights
Lufthansa	Cheapest£409	Average£528	FlexibilityNo cancel fee	On-time76%	Search Lufthansa flights
United Airlines	Cheapest£419	Average£645	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
KLM	Cheapest£421	Average£612	FlexibilityNo cancel fee	On-time75%	Search KLM flights
Aer Lingus	Cheapest£427	Average£690	FlexibilityNo cancel fee	On-timeN/A	Search Aer Lingus flights
Finnair	Cheapest£427	Average£593	FlexibilityNo cancel fee	On-time76%	Search Finnair flights
Delta	Cheapest£444	Average£637	FlexibilityNo cancel fee	On-timeN/A	Search Delta flights
British Airways	Cheapest£450	Average£643	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Virgin Atlantic	Cheapest£468	Average£620	FlexibilityNo cancel fee	On-time72%	Search Virgin Atlantic flights

Fly with Cheapflights

How does Cheapflights help users find flights from Heathrow to Seattle?

Deals for Heathrow to Seattle flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from Heathrow to Seattle?

Cheapflights helps you find that perfect flight to Seattle from Heathrow by searching from hundreds of airlines and agencies you know and love. We are also free to use, in case you were wondering!

Can Cheapflights find flights from Heathrow to Seattle with no change fees?

Need flexible booking options for your flight to Seattle from Heathrow? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

Can Cheapflights notify me if prices for flights from Heathrow to Seattle become cheaper?

Yes! Start tracking prices for Heathrow to Seattle flights today and get alerted whenever prices for these flights change. To access this feature, click the bell icon next to the flight deals above, which will prompt you for a valid email address to receive your alerts.

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Cheap flights from London Heathrow Airport to Seattle from £393

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 28/4. Fares are subject to change and may not be available on all flights or dates of travel.

Cheapflights Tip: The best prices from London Heathrow to Seattle/Tacoma Intl are usually found in February or November, booked 54 days in advance, depart on a Tuesday or Wednesday and return on a Monday

Cheap flight deals from Heathrow to Seattle

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Heathrow to Seattle

Cheapest flights from Heathrow to SeattleExplore the most affordable flight options available from Heathrow to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 20 March 2025.

Explore the most affordable flight options available from Heathrow to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 20 March 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from London Heathrow Airport to Seattle that are best for you.

Best time to book a flight from Heathrow to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Heathrow with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from London Heathrow Airport to Seattle

How far ahead should I book a flight from London Heathrow Airport to Seattle?

Use this chart to determine the optimal time to book a return flight from Heathrow to Seattle. Price data was last updated on 14 March 2025.

What is the cheapest month to book a flight from London Heathrow Airport to Seattle?

What is the cheapest time of day to fly from LHR to SEA?

Find hourly flight availability from Heathrow to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 20 March 2025.

What is the cheapest day to fly from London Heathrow Airport to Seattle?

Use this chart to determine the cheapest time to fly return from Heathrow to Seattle. Price data was last updated on 16 March 2025.

Weekly flight availability from London Heathrow Airport to Seattle

Explore weekly flight availability from Heathrow to Seattle. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated 20 March 2025.

Rainfall in Seattle by month

Plan your trip to Seattle by taking into account the average rainfall totals by month.

Temperature in Seattle by month

Plan your trip to Seattle by taking into account the average temperature totals by month.

Reviews of airlines servicing Seattle

Get a feel of what it's like to fly with Delta, KLM and Finnair from London to Seattle by reading reviews from past customers. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Heathrow to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What airport do you fly into for flights to Seattle from London Heathrow?

What are the cheapest airlines flying from London Heathrow Airport to Seattle round-trip?

What are the cheapest airlines to fly from London Heathrow Airport to Seattle one-way?

What are the most reliable airlines from London Heathrow Airport to Seattle?

What are the cheapest flights from London Heathrow Airport to Seattle?

Can I find deals for flights from Heathrow to Seattle that include hotel bookings?

How can I find direct flights from Heathrow to Seattle?

Can I find deals for business class flights from Heathrow to Seattle?

What is the cheapest month to book a flight from London Heathrow Airport to Seattle?

Travelling to a place near London Heathrow Airport?

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Fly from Heathrow to Seattle on these airlines

Choose from the following airlines for your flight from Heathrow to Seattle. Flights are based on user searches made on Cheapflights and were last updated on 20 March 2025.

Top 10 airlines flying from Heathrow to Seattle

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Cheapest flights from Heathrow to Seattle
Explore the most affordable flight options available from Heathrow to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 20 March 2025.