HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Heathrow

$272+ Cheap flights from Seattle (SEA) to Heathrow (LHR)

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 2/25. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — LHR
Jan 28 — Feb 41
Tue 1/28
Tue 2/4
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Seattle to Heathrow with Cheapflights

1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”
2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.
3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

The best prices from Seattle/Tacoma Intl to London Heathrow are usually found in November or February, booked 75 days in advance, depart on a Tuesday or Sunday and return on a Wednesday

Cheap flight deals from Seattle to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Heathrow (LHR). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated January 23, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$584
(Mytrip)

One-way from

$279
(Kiwi.com)

Popular in

June

Cheapest in

November

Average price

$739

Good round-trip deal

$709 or less

Good one-way deal

$466 or less
Provider with most accurate pricing for Seattle/Tacoma Intl-London Heathrow flight deals.
Search Deals
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-London Heathrow flights.
Search Deals
From Seattle/Tacoma Intl to London Heathrow
Search Deals
One-way flight from Seattle/Tacoma Intl to London Heathrow
Search Deals
Highest demand for flights based on searches. 21% potential increase in price ($226 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($35 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2025
Search Deals
Price to beat on a round-trip flight from Seattle/Tacoma Intl to London Heathrow.
Search Deals
Price to beat on a one-way flight from Seattle/Tacoma Intl to London Heathrow.
Search Deals

Find flight deals from Seattle to Heathrow

Cheapest flights from Seattle to Heathrow
Explore the most affordable flight options available from Seattle to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 23, 2025.

This Mytrip deal was found by Cheapflights users on 1/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/172:35 pmSEA - LHR
1 stop12h 15mIcelandair
Mon 3/312:15 pmLHR - SEA
1 stop12h 45mIcelandair
Deal found 1/22$584
This Cheapflightsfares deal was found by Cheapflights users on 1/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/111:35 pmSEA - LHR
Nonstop9h 25mIberia
Wed 2/263:00 pmLHR - SEA
Nonstop9h 55mIberia
Deal found 1/21$586
This Expedia deal was found by Cheapflights users on 1/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/198:00 pmSEA - LHR
1 stop11h 35mAer Lingus
Wed 2/269:50 amLHR - SEA
1 stop16h 25mAer Lingus
Deal found 1/22$589
This Gotogate deal was found by Cheapflights users on 1/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/35:45 pmSEA - LHR
Nonstop9h 25mVirgin Atlantic
Thu 3/136:20 amLHR - SEA
1 stop13h 00mVirgin Atlantic
Deal found 1/22$603
This lol.travel deal was found by Cheapflights users on 1/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure lol.travel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/183:05 pmSEA - LHR
1 stop12h 05mAir Canada
Tue 3/258:55 amLHR - SEA
2 stops19h 35mAir Canada
Deal found 1/23$604
This Delta deal was found by Cheapflights users on 1/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/195:45 pmSEA - LHR
Nonstop9h 25mDelta
Fri 2/286:30 amLHR - SEA
1 stop13h 16mDelta
Deal found 1/21$613
This KLM deal was found by Cheapflights users on 1/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/31:30 pmSEA - LHR
1 stop12h 30mKLM
Thu 3/136:30 amLHR - SEA
1 stop13h 10mKLM
Deal found 1/22$616
This Air Canada deal was found by Cheapflights users on 1/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/49:20 amSEA - LHR
2 stops16h 50mMultiple Airlines
Wed 3/128:55 amLHR - SEA
2 stops19h 35mMultiple Airlines
Deal found 1/22$619
This Finnair deal was found by Cheapflights users on 1/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/46:50 pmSEA - LHR
Nonstop9h 25mFinnair
Tue 3/119:25 amLHR - SEA
Nonstop9h 55mFinnair
Deal found 1/22$620
This oojo deal was found by Cheapflights users on 1/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/213:05 pmSEA - LHR
2 stops31h 25mLufthansa
Wed 4/3010:50 amLHR - SEA
1 stop14h 09mLufthansa
Deal found 1/23$637
This United Airlines deal was found by Cheapflights users on 1/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/147:05 pmSEA - LHR
1 stop34h 15mUnited Airlines
Mon 5/51:30 pmLHR - SEA
2 stops32h 43mUnited Airlines
Deal found 1/23$640
This SWISS deal was found by Cheapflights users on 1/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure SWISS is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/33:25 pmSEA - LHR
2 stops19h 50mSWISS
Mon 2/248:05 pmLHR - SEA
2 stops34h 37mSWISS
Deal found 1/23$642

Find flights from Seattle to Heathrow within your budget

Customize your flight search to find flights from Seattle to Heathrow that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated January 23, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 2/17

2:35 pm-10:50 am

1 stop12h 15m

London Heathrow

Mon 3/3

12:15 pm-5:00 pm

1 stop12h 45m

$584

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 2/11

1:35 pm-7:00 am

Nonstop9h 25m

London Heathrow

Wed 2/26

3:00 pm-4:55 pm

Nonstop9h 55m

$586

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 2/19

8:00 pm-3:35 pm

1 stop11h 35m

London Heathrow

Wed 2/26

9:50 am-6:15 pm

1 stop16h 25m

$589

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 3/3

5:45 pm-11:10 am

Nonstop9h 25m

London Heathrow

Thu 3/13

6:20 am-12:20 pm

1 stop13h 00m

$603

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 3/18

3:05 pm-10:10 am

1 stop12h 05m

London Heathrow

Tue 3/25

8:55 am-9:30 pm

2 stops19h 35m

$604

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 4/29

10:35 am-10:00 am

2 stops15h 25m

London Heathrow

Tue 5/13

8:45 am-6:33 pm

2 stops17h 48m

$612

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 2/19

5:45 pm-11:10 am

Nonstop9h 25m

London Heathrow

Fri 2/28

6:30 am-11:46 am

1 stop13h 16m

$613

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 3/3

1:30 pm-10:00 am

1 stop12h 30m

London Heathrow

Thu 3/13

6:30 am-12:40 pm

1 stop13h 10m

$616

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 3/4

7:32 pm-7:25 am

1 stop27h 53m

London Heathrow

Wed 3/12

1:00 pm-9:50 am

1 stop27h 50m

$620

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 2/17

10:35 am-10:10 am

1 stop15h 35m

London Heathrow

Mon 3/3

8:15 pm-1:20 pm

1 stop25h 05m

$636

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/22

Showing 1-10 of 29 results
1
2
3

Compare providers for flights from Seattle to Heathrow

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Heathrow in January.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*1 star
CheapfaremartPrice Accuracy-Trust Score*1 star
CheapOairPrice Accuracy2 starsTrust Score*2 stars
GotogatePrice Accuracy2 starsTrust Score*2 stars
oojoPrice Accuracy3 starsTrust Score*2 stars
SmartFaresPrice Accuracy1 starTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-London Heathrow Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-London Heathrow Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-London Heathrow Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-London Heathrow Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-London Heathrow Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Seattle to Heathrow

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

Travel insights for flights from Seattle to Heathrow

Get recent, data-driven insights about flights from Seattle to Heathrow including ideal travel times, pricing trends, and more.

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

Use this chart to determine the optimal time to book a round-trip flight from Seattle to Heathrow. Price data was last updated on January 17, 2025.

Booking 75 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to London Heathrow Airport. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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

Currently, November is the cheapest month in which you can book a flight from Seattle to London Heathrow Airport (average of $661). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of $1,137). 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 SEA to LHR?

Find hourly flight availability from Seattle to Heathrow. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated January 23, 2025.

When flying from Seattle to London Heathrow Airport, the time of day you fly usually plays a role in the price. Save by searching for a flight in the afternoon, which can drop the price by up to 10% versus a flight in the morning.

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

Use this chart to determine the cheapest time to fly round-trip from Seattle to Heathrow. Price data was last updated on December 16, 2024.

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

Weekly flight availability from Seattle to London Heathrow Airport

Explore weekly flight availability from Seattle to Heathrow. 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 January 23, 2025.

The most flights from SEA to LHR are scheduled on a Wednesday (16 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (11 on average).

Rainfall in Heathrow by month

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

In terms of precipitation, rainfall in London Heathrow Airport ranges from 1.6 - 2.8 inches per month. January is typically the wettest month, when rainfall can reach 2.8 in. July is typically the driest time to visit London Heathrow Airport when rainfall is around 1.6 in.

Temperature in Heathrow by month

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

If weather is an important factor for your trip to London Heathrow Airport, 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 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 39.2 F).

Reviews of airlines servicing Heathrow

Get insights into the airlines that provide service to Heathrow. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Heathrow. Reviews last updated January 23, 2025.
Peruse reviews from past customers who have flown with Icelandair, Iberia and Lufthansa from Seattle to London to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
8,512 reviews

Boarding

8.2

Food

7.3

Crew

8.6

Entertainment

7.9

Comfort

8.0

Overall

8.0

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Delta
8.0
Very good
8,512 reviews
Delta
8.0
Very good
8,512 reviews

Boarding

8.2

Food

7.3

Crew

8.6

Entertainment

7.9

Comfort

8.0

Overall

8.0

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

KLM
7.8
Good
1,338 reviews
Delta
8.0
Very good
8,512 reviews

Boarding

8.2

Food

7.3

Crew

8.6

Entertainment

7.9

Comfort

8.0

Overall

8.0

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Finnair
7.6
Good
1,286 reviews
Delta
8.0
Very good
8,512 reviews

Boarding

8.2

Food

7.3

Crew

8.6

Entertainment

7.9

Comfort

8.0

Overall

8.0

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

SWISS
7.5
Good
1,598 reviews
Delta
8.0
Very good
8,512 reviews

Boarding

8.2

Food

7.3

Crew

8.6

Entertainment

7.9

Comfort

8.0

Overall

8.0

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Virgin Atlantic
7.5
Good
663 reviews
Delta
8.0
Very good
8,512 reviews

Boarding

8.2

Food

7.3

Crew

8.6

Entertainment

7.9

Comfort

8.0

Overall

8.0

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Heathrow. 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 from for flights from Seattle to London Heathrow?

    Seattle/Tacoma Intl (SEA) is the airport you will fly out of if you book a flight from Seattle to London Heathrow. You should not have trouble finding flights to London Heathrow from Seattle/Tacoma Intl; the airport handles an average of 13 outbound flights to London Heathrow per day. You should also have plenty of airline options to choose from since 15 airlines have flights from the Seattle airport to London Heathrow. It is only a 11.4 mi journey to Seattle/Tacoma Intl (SEA) from Seattle’s city center.

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

    Our cheapest airline available from Seattle to London Heathrow Airport is Icelandair. Our recent data shows that you can find tickets from as low as $584 on this airline. Additional options worth looking into are Iberia and Aer Lingus, starting at $586 and $589 round-trip. Icelandair is currently priced 29% below the average price you’ll pay for this route.

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

    The cheapest airlines for a one-way flight from Seattle to London Heathrow Airport are WestJet ($279), Icelandair ($284), and JetBlue ($367).

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

    No one likes to see their flight delayed. When booking a flight from Seattle to London Heathrow Airport consider choosing Singapore Airlines (85%), Aeromexico (85%) or KLM (80%) as they are the most reliable in getting you off to your destination on time.

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

    Looking for the cheapest flight from Seattle to London Heathrow Airport? While on average our users pay $1,691, our data indicates the cheapest price to be $410. The most popular route (Seattle/Tacoma Intl - London Heathrow), is priced around $475.

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

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

  • How can I find direct flights from Seattle to Heathrow?

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

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

    Yes. Cheapflights offers flight deals from Seattle to Heathrow 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 Seattle to London Heathrow Airport?

    Currently, November is the cheapest month in which you can book a flight from Seattle to London Heathrow Airport (average of $661). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of $1,137). 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

Traveling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Hayes
Hounslow
Thornton Heath
Harrow
Luton
Wembley
Canterbury
Northampton
Gatwick
Horley
Milton Keynes
Dover
Orpington
Watford
Stratford-upon-Avon
Croydon
Borehamwood
Bromley
Folkestone
Ilford

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Top 10 airlines flying from Seattle to Heathrow

Discover the top 10 airlines that operate flights from Seattle to Heathrow. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated January 23, 2025.
AirlineCheapestAverageFlexibilityOn-time
LufthansaCheapest$384Average$690FlexibilityNo cancel feeOn-time76%
FinnairCheapest$493Average$762FlexibilityNo cancel feeOn-time76%
IcelandairCheapest$498Average$670FlexibilityNo cancel feeOn-time76%
IberiaCheapest$582Average$751FlexibilityNo cancel feeOn-time77%
Air FranceCheapest$588Average$901FlexibilityNo cancel feeOn-time77%
Aer LingusCheapest$588Average$855FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$597Average$840FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$599Average$896FlexibilityNo cancel feeOn-time71%
DeltaCheapest$599Average$883FlexibilityNo cancel feeOn-timeN/A
Virgin AtlanticCheapest$606Average$888FlexibilityNo cancel feeOn-time72%
100% Free
Cheapflights is completely free to use, so you can start saving the moment you arrive.
Book with Flexibility
Our users can plan ahead with confidence and find flights with no change fees
Travel Smart
Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.