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 Delta. Our recent data shows that you can find tickets from as low as $574 on this airline. Additional options worth looking into are Air Canada and British Airways, starting at $576 and $577 round-trip. Delta is currently priced 29% below the average price you’ll pay for this route.

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.

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).

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 $3,303, our data indicates the cheapest price to be $357. The most popular route (Seattle/Tacoma Intl - London Heathrow), is priced around $420.

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 Scandinavian Airlines (93%), KLM (92%) or Air France (92%) as they are the most reliable in getting you off to your destination on time.

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

Before booking your flight from Seattle to London Heathrow Airport check out the most popular airlines for this route: American Airlines, Air Canada or Air France.

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

Departing on a Monday is a good option for securing a great price. You can expect to save up to 15% when planning your travel around this day of the week.

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

To save up to 43% on this flight, we recommend booking at least 51 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Seattle to London Heathrow Airport from $862 1-2 weeks out and tickets from $989 for flights departing within the next 72 hours.

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

The best pricing can be found in the month of October. Prices to London Heathrow Airport from Seattle average $779. You can even find prices in October for less than $779, as users have found deals to London Heathrow Airport from as low as $540. The month of June appears to be one of the more expensive times to travel to London Heathrow Airport from Seattle. Flying in the targeted month can save you up to 32%.

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 21 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.

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.

$220+ Flights from Seattle to London Heathrow Airport

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1. Tell us where you want to go

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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London Heathrow are usually found in March or April, booked 32 days in advance, depart on a Tuesday or Monday and return on a Wednesday

Cheap flight deals from Seattle to Heathrow

Round-trip from	$574 (Delta)
One-way from	$220 (Icelandair)
Popular in	June
Cheapest in	March
Average price	$1,017
Good round-trip deal	$656 or less
Good one-way deal	$427 or less

From Seattle/Tacoma Intl to London Heathrow

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One-way flight from Seattle/Tacoma Intl to London Heathrow

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Highest demand for flights based on searches. 18% potential increase in price ($178 potential increase over avg. RT price).

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Cheapest flight prices on average. 3% potential price decrease ($29 potential savings vs. average RT price).

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Average for round-trip flights in July 2025

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

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

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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 July 3, 2025.

Sun 8/178:25 pmSEA - LHR

Nonstop9h 50mVirgin Atlantic

Sun 8/246:30 pmLHR - SEA

Nonstop10h 20mVirgin Atlantic

Deal found 7/3

$570

Thu 10/97:00 pmSEA - LHR

1 stop32h 55mIcelandair

Tue 10/219:25 pmLHR - SEA

1 stop31h 15mIcelandair

Deal found 7/3

$573

Wed 8/137:18 amSEA - LHR

1 stop18h 57mDelta

Mon 9/15:25 pmLHR - SEA

Nonstop10h 25mDelta

Deal found 7/2

$574

Thu 10/91:30 pmSEA - LHR

Nonstop9h 20mBritish Airways

Tue 10/214:30 pmLHR - SEA

Nonstop9h 50mBritish Airways

Deal found 7/3

$575

Mon 10/68:00 amSEA - LHR

2 stops29h 40mAustrian Airlines

Mon 10/207:30 pmLHR - SEA

2 stops33h 14mAustrian Airlines

Deal found 7/1

$576

Thu 10/910:00 amSEA - LHR

1 stop19h 20mAir Canada

Tue 10/218:45 amLHR - SEA

2 stops17h 51mAir Canada

Deal found 7/3

$580

Wed 7/167:35 pmSEA - LHR

1 stop12h 20mAer Lingus

Wed 8/61:25 pmLHR - SEA

1 stop12h 25mAer Lingus

Deal found 7/2

$581

Wed 10/293:37 pmSEA - LHR

2 stops19h 13mSWISS

Tue 11/118:55 amLHR - SEA

2 stops22h 20mSWISS

Deal found 7/3

$584

Wed 9/310:00 amSEA - LHR

2 stops15h 35mLufthansa

Mon 9/157:30 pmLHR - SEA

2 stops26h 46mLufthansa

Deal found 7/2

$589

Sun 8/175:10 amSEA - LHR

1 stop18h 15mUnited Airlines

Sun 8/247:25 amLHR - SEA

2 stops23h 34mUnited Airlines

Deal found 7/3

$598

Fri 8/151:30 pmSEA - LHR

1 stop12h 20mMultiple Airlines

Fri 8/226:00 pmLHR - SEA

Nonstop10h 20mMultiple Airlines

Deal found 7/1

$601

Mon 7/281:18 pmSEA - LHR

1 stop13h 02mFinnair

Mon 8/1110:20 amLHR - SEA

1 stop13h 40mFinnair

Deal found 7/2

$616

Best flights from Seattle to Heathrow
Discover carefully curated flight deals from Seattle to Heathrow that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 3, 2025.

Wed 8/137:18 amSEA - LHR

1 stop18h 57mDelta

Mon 9/15:25 pmLHR - SEA

Nonstop10h 25mDelta

Deal found 7/2

$574

Wed 8/275:30 amSEA - LHR

2 stops17h 00mAir Canada

Wed 9/108:40 amLHR - SEA

2 stops18h 51mAir Canada

Deal found 7/3

$576

Tue 9/168:20 pmSEA - LHR

Nonstop9h 20mBritish Airways

Tue 9/239:25 amLHR - SEA

Nonstop9h 45mBritish Airways

Deal found 7/2

$577

Wed 7/167:35 pmSEA - LHR

1 stop12h 20mAer Lingus

Wed 8/61:25 pmLHR - SEA

1 stop12h 25mAer Lingus

Deal found 7/2

$581

Mon 7/75:15 amSEA - LHR

1 stop19h 45mIberia

Mon 9/157:25 pmLHR - SEA

2 stops32h 44mIberia

Deal found 6/30

$585

Sun 8/246:50 pmSEA - LHR

2 stops14h 50mLufthansa

Wed 9/176:55 amLHR - SEA

1 stop18h 04mLufthansa

Deal found 7/1

$588

Tue 8/268:25 pmSEA - LHR

Nonstop9h 50mMultiple Airlines

Mon 9/88:40 amLHR - SEA

1 stop15h 25mMultiple Airlines

Deal found 7/2

$592

Tue 8/2610:00 amSEA - LHR

2 stops25h 20mSWISS

Fri 9/56:00 amLHR - SEA

2 stops20h 36mSWISS

Deal found 7/2

$596

Tue 7/2211:15 amSEA - LHR

1 stop14h 35mVirgin Atlantic

Tue 8/512:55 pmLHR - SEA

1 stop17h 53mVirgin Atlantic

Deal found 7/1

$597

Sun 8/177:20 amSEA - LHR

1 stop18h 40mUnited Airlines

Mon 8/256:50 amLHR - SEA

2 stops21h 52mUnited Airlines

Deal found 7/3

$598

Sun 8/243:45 pmSEA - LHR

1 stop12h 10mIcelandair

Fri 9/121:05 pmLHR - SEA

1 stop15h 35mIcelandair

Deal found 7/1

$604

Mon 7/281:18 pmSEA - LHR

1 stop13h 02mFinnair

Mon 8/1110:20 amLHR - SEA

1 stop13h 40mFinnair

Deal found 7/2

$616

Last-minute flights from Seattle to Heathrow
Discover last-minute flight deals from Seattle to Heathrow. Data last updated July 3, 2025 and is based on user searches.

Mon 7/75:15 amSEA - LHR

1 stop19h 45mIberia

Mon 9/157:25 pmLHR - SEA

2 stops32h 44mIberia

Deal found 6/30

$585

Tue 7/812:15 pmSEA - LHR

2 stops21h 25mScandinavian Airlines

Tue 7/157:30 pmLHR - SEA

1 stop26h 20mScandinavian Airlines

Deal found 7/1

$790

Wed 7/910:00 amSEA - LHR

2 stops16h 00mLufthansa

Thu 7/247:10 pmLHR - SEA

1 stop29h 49mLufthansa

Deal found 7/2

$611

Wed 7/93:13 pmSEA - LHR

1 stop13h 02mIberia

Fri 7/258:20 amLHR - SEA

1 stop22h 42mIberia

Deal found 7/2

$632

Wed 7/91:30 pmSEA - LHR

Nonstop9h 20mAmerican Airlines

Tue 7/221:30 pmLHR - SEA

1 stop16h 13mAmerican Airlines

Deal found 7/2

$743

Sat 7/127:15 pmSEA - LHR

1 stop34h 05mMultiple Airlines

Thu 7/248:40 amLHR - SEA

2 stops17h 56mMultiple Airlines

Deal found 6/30

$672

Sat 7/124:20 pmSEA - LHR

2 stops45h 10mSWISS

Wed 7/238:05 pmLHR - SEA

2 stops30h 31mSWISS

Deal found 6/30

$785

Sun 7/135:35 pmSEA - LHR

Nonstop9h 45mDelta

Thu 7/246:30 amLHR - SEA

1 stop13h 05mDelta

Deal found 7/2

$610

Sun 7/1310:56 amSEA - LHR

2 stops15h 04mUnited Airlines

Fri 7/256:30 amLHR - SEA

1 stop13h 25mUnited Airlines

Deal found 7/2

$757

Sun 7/132:55 pmSEA - LHR

2 stops31h 35mAir Canada

Tue 7/222:05 pmLHR - SEA

2 stops28h 55mAir Canada

Deal found 7/1

$805

Wed 7/167:35 pmSEA - LHR

1 stop12h 20mAer Lingus

Wed 8/61:25 pmLHR - SEA

1 stop12h 25mAer Lingus

Deal found 7/2

$581

Tue 7/291:30 pmSEA - LHR

Nonstop9h 20mBritish Airways

Tue 8/129:25 amLHR - SEA

Nonstop9h 45mBritish Airways

Deal found 7/2

$577

One-way flights from Seattle to Heathrow
Search for one-way flight options from Seattle to Heathrow. Find affordable one-way fares based on user searches. Data last updated July 3, 2025.

Mon 9/153:45 pmSEA - LHR

1 stop12h 10mIcelandair

Deal found 7/1

$220

Tue 9/303:45 pmSEA - LHR

2 stops21h 50mMultiple Airlines

Deal found 7/1

$253

Cheapflights Fare Finder

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

Fly from

Fly to

Route

Depart

Return

Price

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Sun 8/17

8:25 pm-2:15 pm

Nonstop9h 50m

London Heathrow

Sun 8/24

6:30 pm-8:50 pm

Nonstop10h 20m

$570

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 8/13

3:05 pm-2:35 pm

1 stop15h 30m

London Heathrow

Sun 8/24

6:30 pm-8:50 pm

Nonstop10h 20m

$574

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 8/27

5:30 am-6:30 am

2 stops17h 00m

London Heathrow

Wed 9/10

8:40 am-7:31 pm

2 stops18h 51m

$576

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 9/16

8:20 pm-1:40 pm

Nonstop9h 20m

London Heathrow

Tue 9/23

9:25 am-11:10 am

Nonstop9h 45m

$577

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 7/16

7:35 pm-3:55 pm

1 stop12h 20m

London Heathrow

Wed 8/6

1:25 pm-5:50 pm

1 stop12h 25m

$581

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 7/7

5:15 am-9:00 am

1 stop19h 45m

London Heathrow

Mon 9/15

7:25 pm-8:09 pm

2 stops32h 44m

$585

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Sun 8/24

6:50 pm-8:40 pm

2 stops17h 50m

London Heathrow

Fri 9/12

6:55 am-4:59 pm

1 stop18h 04m

$588

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 8/26

10:00 am-7:20 pm

2 stops25h 20m

London Heathrow

Fri 9/5

6:00 am-6:36 pm

2 stops20h 36m

$596

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Sun 8/17

7:20 am-10:00 am

1 stop18h 40m

London Heathrow

Mon 8/25

6:50 am-8:42 pm

2 stops21h 52m

$598

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Fri 8/15

1:30 pm-9:50 am

1 stop12h 20m

London Heathrow

Fri 8/22

6:00 pm-8:20 pm

Nonstop10h 20m

$601

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/1

Showing 1-10 of 15 results

The best insider tips for Seattle to London Heathrow Airport flights

Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to London Heathrow Airport trip

Airports

SEA

Use SEA Spot Saver to book security screening appointments in advance, reducing wait times without needing TSA PreCheck or CLEAR.

LHR

Take the Heathrow Express for the fastest route to central London, reaching Paddington Station quickly and conveniently.

Our travel experts

Ramsey Qubein

Expert on LHR

Brandon Schultz

Expert on SEA

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.

Cheapflights Insights

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

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

Booking 32 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 $1,098). 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?

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 evening, which can drop the price by up to 13% versus a flight in the morning.

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

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

The most flights from SEA to LHR are scheduled on a Monday (22 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (16 on average).

Reviews of airlines servicing Heathrow

Read reviews from past customers who have flown Delta, Finnair, and SWISS from Seattle to London Heathrow Airport. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Delta

8.0

Very good

7,982 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Delta

8.0

Very good

7,982 reviews

Delta

8.0

Very good

7,982 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Finnair

7.6

Good

1,306 reviews

Delta

8.0

Very good

7,982 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

SWISS

7.5

Good

1,654 reviews

Delta

8.0

Very good

7,982 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

United Airlines

7.4

Good

8,861 reviews

Delta

8.0

Very good

7,982 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Virgin Atlantic

7.4

Good

654 reviews

Delta

8.0

Very good

7,982 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Related info for your journey

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 21 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 Delta. Our recent data shows that you can find tickets from as low as $574 on this airline. Additional options worth looking into are Air Canada and British Airways, starting at $576 and $577 round-trip. Delta is currently priced 29% below the average price you’ll pay for this route.
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 Scandinavian Airlines (93%), KLM (92%) or Air France (92%) 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 $3,303, our data indicates the cheapest price to be $357. The most popular route (Seattle/Tacoma Intl - London Heathrow), is priced around $420.
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 $1,098). 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

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Top 10 airlines flying from Seattle to Heathrow

Airline	Cheapest	Average	Flexibility	On-time
Lufthansa	Cheapest$378	Average$819	FlexibilityNo cancel fee	On-time76%
United Airlines	Cheapest$498	Average$870	FlexibilityNo cancel fee	On-time69%
Icelandair	Cheapest$506	Average$664	FlexibilityNo cancel fee	On-time76%
Scandinavian Airlines	Cheapest$532	Average$741	FlexibilityNo cancel fee	On-time77%
Finnair	Cheapest$556	Average$725	FlexibilityNo cancel fee	On-time76%
Iberia	Cheapest$579	Average$733	FlexibilityNo cancel fee	On-time77%
Aer Lingus	Cheapest$583	Average$793	FlexibilityNo cancel fee	On-timeN/A
Air France	Cheapest$597	Average$880	FlexibilityNo cancel fee	On-time77%
KLM	Cheapest$597	Average$825	FlexibilityNo cancel fee	On-time75%
British Airways	Cheapest$605	Average$848	FlexibilityNo cancel fee	On-time70%

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$220+ 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 9/15. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Seattle to Heathrow with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London Heathrow are usually found in March or April, booked 32 days in advance, depart on a Tuesday or Monday and return on a Wednesday

Cheap flight deals from Seattle to Heathrow

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Seattle to Heathrow

Cheapest flights from Seattle to HeathrowExplore 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 July 3, 2025.

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 July 3, 2025.

Cheapflights Fare Finder

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

The best insider tips for Seattle to London Heathrow Airport flights

Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to London Heathrow Airport trip

Airports

SEA

LHR

Our travel experts

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.

Cheapflights Insights

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

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 June 27, 2025.

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

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 July 3, 2025.

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.

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 July 3, 2025.

Reviews of airlines servicing Heathrow

Read reviews from past customers who have flown Delta, Finnair, and SWISS from Seattle to London Heathrow Airport. Users can see the overall rating for each airline as well as how each is rated 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 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?

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

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

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

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

How can I find direct flights from Seattle to Heathrow?

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

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

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Alternative routes for Seattle to Heathrow

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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 July 3, 2025.