How long is the flight from Portland, Maine to London Heathrow Airport?

There are many flights that can get you from Portland, Maine to London Heathrow Airport in 11h 20m. Fly via American Airlines, Delta, or United Airlines to get the fastest option. There are 3173 mi between Portland, Maine and London Heathrow Airport. Both multi-stop and nonstop flights can be found to your destination and back.

What are the cheapest airlines flying from Portland, Maine to London Heathrow Airport round-trip?

United Airlines, at $648, was found to be the cheapest airline from Portland, Maine to London Heathrow Airport. An alternate airline flying to your destination would be Delta. These flights start at 33% lower than the current average price 3 months from now.

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 is the cheapest time of day to fly from PWM to LHR?

When flying from Portland, Maine to London Heathrow Airport, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Most accurate provider : When it comes to deals on Portland, Maine-London Heathrow Airport flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Portland, Maine-London Heathrow Airport flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Portland, Maine-London Heathrow Airport flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on Portland, Maine-London Heathrow Airport flights, Cheapflights users trust eDreams the most. eDreams 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 Portland, Maine-London Heathrow Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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

Portland (PWM) is the airport you will fly out of if you book a flight from Portland to London Heathrow. You should not have trouble finding flights to London Heathrow from Portland; the airport handles an average of 0 outbound flights to London Heathrow per day. You should also have plenty of airline options to choose from since 2 airlines have flights from the Portland airport to London Heathrow. It is only a 2.9 mi journey to Portland (PWM) from Portland’s city center.

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

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

How can I find direct flights from Portland to Heathrow?

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

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

Yes. Cheapflights offers flight deals from Portland 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.

$628+ Flights from Portland, ME to London Heathrow Airport

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Cheap flight deals from Portland to Heathrow

Cheapest flights from Portland to Heathrow
Explore the most affordable flight options available from Portland to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 2, 2026.

Wed 12/319:30 amPWM - LHR

2 stops17h 55mUnited Airlines

Mon 1/54:20 pmLHR - PWM

1 stop27h 11mUnited Airlines

Deal found 12/30

$1,017

Wed 12/319:30 amPWM - LHR

1 stop15h 25mSWISS

Mon 1/54:20 pmLHR - PWM

1 stop27h 11mSWISS

Deal found 12/30

$1,046

Best flights from Portland to Heathrow
Discover carefully curated flight deals from Portland to Heathrow that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated January 2, 2026.

Fri 2/275:40 pmPWM - LHR

1 stop12h 55mAmerican Airlines

Mon 3/27:50 amLHR - PWM

2 stops15h 21mAmerican Airlines

Deal found 1/1

$628

Fri 3/62:35 pmPWM - LHR

1 stop11h 20mDelta

Fri 3/138:40 amLHR - PWM

2 stops19h 19mDelta

Deal found 12/31

$631

Thu 3/56:00 amPWM - LHR

2 stops20h 10mUnited Airlines

Thu 3/126:50 amLHR - PWM

2 stops15h 35mUnited Airlines

Deal found 12/31

$633

Sat 2/146:00 amPWM - LHR

2 stops20h 10mAir Canada

Sat 2/219:00 amLHR - PWM

2 stops43h 20mAir Canada

Deal found 12/31

$653

Thu 3/52:35 pmPWM - LHR

1 stop14h 40mKLM

Thu 3/1210:10 amLHR - PWM

1 stop17h 49mKLM

Deal found 12/31

$658

Thu 2/123:05 pmPWM - LHR

2 stops15h 15mUnited Airlines

Thu 2/1912:05 pmLHR - PWM

2 stops16h 15mUnited Airlines

Deal found 1/1

$639

Tue 3/314:48 pmPWM - LHR

1 stop11h 07mDelta

Tue 4/149:55 amLHR - PWM

2 stops19h 51mDelta

Deal found 12/31

$646

Thu 2/122:35 pmPWM - LHR

1 stop14h 40mKLM

Thu 2/1910:10 amLHR - PWM

1 stop19h 08mKLM

Deal found 1/1

$659

Tue 5/121:35 pmPWM - LHR

2 stops18h 30mDelta

Wed 5/208:40 amLHR - PWM

2 stops20h 19mDelta

Deal found 12/31

$651

Last-minute flights from Portland to Heathrow
Discover last-minute flight deals from Portland to Heathrow. Data last updated January 2, 2026 and is based on user searches.

Tue 1/62:30 pmPWM - LHR

1 stop11h 25mDelta

Tue 1/1310:00 amLHR - PWM

2 stops19h 26mDelta

Deal found 12/30

$796

Tue 1/611:12 amPWM - LHR

2 stops15h 43mUnited Airlines

Tue 1/136:50 amLHR - PWM

2 stops36h 49mUnited Airlines

Deal found 12/30

$806

Thu 1/88:40 amPWM - LHR

1 stop19h 30mAustrian Airlines

Thu 1/1512:00 pmLHR - PWM

1 stop11h 50mAustrian Airlines

Deal found 1/1

$843

Thu 1/83:12 pmPWM - LHR

1 stop10h 08mUnited Airlines

Thu 1/156:50 amLHR - PWM

2 stops17h 00mUnited Airlines

Deal found 1/1

$846

Sat 1/176:00 amPWM - LHR

1 stop10h 20mUnited Airlines

Mon 1/191:25 pmLHR - PWM

2 stops29h 31mUnited Airlines

Deal found 12/30

$839

Thu 1/292:31 pmPWM - LHR

1 stop11h 09mUnited Airlines

Thu 2/56:50 amLHR - PWM

2 stops17h 00mUnited Airlines

Deal found 12/31

$630

Thu 1/298:40 amPWM - LHR

1 stop20h 45mAustrian Airlines

Thu 2/59:10 amLHR - PWM

1 stop14h 40mAustrian Airlines

Deal found 12/31

$639

Thu 1/292:35 pmPWM - LHR

3 stops19h 00mScandinavian Airlines

Thu 2/56:40 amLHR - PWM

2 stops22h 40mScandinavian Airlines

Deal found 12/31

$712

Find flight deals from Portland to Heathrow

Most accurate provider	eDreams 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$622 (Expedia)
Popular in	December
Cheapest in	October
Average price	$782

Provider with most accurate pricing for Portland-London Heathrow flight deals.

Search Deals

Provider most trusted by Cheapflights users for Portland-London Heathrow flights.

Search Deals

From Portland to London Heathrow

Search Deals

Highest demand for flights based on searches. 4% potential increase in price ($48 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 4% potential price decrease ($46 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in January 2026

Search Deals

Cheapflights Fare Finder

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

Fly from

Fly to

Route

Depart

Return

Price

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 2/27

5:40 pm-11:35 am

1 stop12h 55m

London Heathrow

Mon 3/2

7:50 am-6:11 pm

2 stops15h 21m

$628

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 3/6

2:35 pm-6:55 am

1 stop11h 20m

London Heathrow

Fri 3/13

8:40 am-11:59 pm

2 stops19h 19m

$631

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 3/5

6:00 am-7:10 am

2 stops20h 10m

London Heathrow

Thu 3/12

6:50 am-6:25 pm

2 stops15h 35m

$633

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 2/12

3:05 pm-11:20 am

2 stops15h 15m

London Heathrow

Thu 2/19

12:05 pm-11:20 pm

2 stops16h 15m

$639

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 3/31

4:48 pm-8:55 am

1 stop11h 07m

London Heathrow

Tue 4/14

9:55 am-12:46 am

2 stops19h 51m

$646

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 5/12

1:35 pm-1:05 pm

2 stops18h 30m

London Heathrow

Wed 5/20

8:40 am-11:59 pm

2 stops20h 19m

$651

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 2/14

6:00 am-7:10 am

2 stops20h 10m

London Heathrow

Sat 2/21

9:00 am-11:20 pm

2 stops43h 20m

$653

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 3/5

2:35 pm-10:15 am

1 stop14h 40m

London Heathrow

Thu 3/12

10:10 am-11:59 pm

1 stop17h 49m

$658

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 2/12

2:35 pm-10:15 am

1 stop14h 40m

London Heathrow

Thu 2/19

10:10 am-12:18 am

1 stop19h 08m

$659

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/1

Compare providers for flights from Portland to Heathrow

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Portland to Heathrow in January.

Provider	Price Accuracy	Trust Score*
FlightHub	Price Accuracy3 stars	Trust Score*1 star
eDreams	Price Accuracy3 stars	Trust Score*3 stars
Ovago	Price Accuracy2 stars	Trust Score*2 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 Portland, Maine-London Heathrow Airport flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Portland, Maine-London Heathrow Airport flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Portland, Maine-London Heathrow Airport flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on Portland, Maine-London Heathrow Airport flights, Cheapflights users trust eDreams the most. eDreams 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 Portland, Maine-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 Portland to Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow from Portland 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 Portland to London Heathrow Airport

What is the cheapest month to book a flight from Portland, Maine to London Heathrow Airport?

Currently, January is the cheapest month in which you can book a flight from Portland, Maine to London Heathrow Airport (average of $390). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of $594). 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.

Reviews of airlines servicing Heathrow

Read through reviews of airlines operating flights from Portland to London Heathrow Airport, such as Delta and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Delta

7.9

Good

8,021 reviews

Reviews

1 / 20

6.0

Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.

Delta

7.9

Good

8,021 reviews

Delta

7.9

Good

8,021 reviews

Reviews

1 / 20

6.0

Good

Jim,Nov 2025

AVL - ATL

United Airlines

7.4

Good

9,132 reviews

Delta

7.9

Good

8,021 reviews

Reviews

1 / 20

6.0

Good

Jim,Nov 2025

AVL - ATL

Related info for your journey

What airport do you fly from for flights from Portland to London Heathrow?
Portland (PWM) is the airport you will fly out of if you book a flight from Portland to London Heathrow. You should not have trouble finding flights to London Heathrow from Portland; the airport handles an average of 0 outbound flights to London Heathrow per day. You should also have plenty of airline options to choose from since 2 airlines have flights from the Portland airport to London Heathrow. It is only a 2.9 mi journey to Portland (PWM) from Portland’s city center.
How long is the flight from Portland, Maine to London Heathrow Airport?
There are many flights that can get you from Portland, Maine to London Heathrow Airport in 11h 20m. Fly via American Airlines, Delta, or United Airlines to get the fastest option. There are 3173 mi between Portland, Maine and London Heathrow Airport. Both multi-stop and nonstop flights can be found to your destination and back.
What are the cheapest airlines flying from Portland, Maine to London Heathrow Airport round-trip?
United Airlines, at $648, was found to be the cheapest airline from Portland, Maine to London Heathrow Airport. An alternate airline flying to your destination would be Delta. These flights start at 33% lower than the current average price 3 months from now.
Can I find deals for flights from Portland to Heathrow that include hotel bookings?
Yes. In addition to deals on Portland to Heathrow flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Portland to Heathrow?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Portland to Heathrow.
Can I find deals for business class flights from Portland to Heathrow?
Yes. Cheapflights offers flight deals from Portland 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 Portland, Maine to London Heathrow Airport?
Currently, January is the cheapest month in which you can book a flight from Portland, Maine to London Heathrow Airport (average of $390). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of $594). 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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Harrow

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Broadway

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Top 2 airlines flying from Portland to Heathrow

Airline	Cheapest	Average	Flexibility	On-time
United Airlines	Cheapest$648	Average$874	FlexibilityNo cancel fee	On-time69%
Delta	Cheapest$765	Average$1,083	FlexibilityNo cancel fee	On-timeN/A

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$628+ Cheap flights from Portland, ME (PWM) to Heathrow (LHR)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 2/27. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Portland to Heathrow with Cheapflights

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2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from Portland to Heathrow

Cheapest flights from Portland to HeathrowExplore the most affordable flight options available from Portland to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 2, 2026.

Explore the most affordable flight options available from Portland to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 2, 2026.

Find flight deals from Portland to Heathrow

Most accurate provider

Most trusted provider

Round-trip from

Popular in

Cheapest in

Average price

Cheapflights Fare Finder

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

Compare providers for flights from Portland 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 Portland to Heathrow in January.

Best time to book a flight from Portland to Heathrow

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

Cheapflights Insights

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

What is the cheapest month to book a flight from Portland, Maine to London Heathrow Airport?

Reviews of airlines servicing Heathrow

Read through reviews of airlines operating flights from Portland to London Heathrow Airport, such as Delta and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Portland 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 Portland to London Heathrow?

How long is the flight from Portland, Maine to London Heathrow Airport?

What are the cheapest airlines flying from Portland, Maine to London Heathrow Airport round-trip?

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

How can I find direct flights from Portland to Heathrow?

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

What is the cheapest month to book a flight from Portland, Maine to London Heathrow Airport?

Traveling to a place near London Heathrow Airport?

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.

Alternative routes for Portland to Heathrow

See prices for flight routes from nearby airports that may be better suited for you.

Top 2 airlines flying from Portland to Heathrow

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Cheapest flights from Portland to Heathrow
Explore the most affordable flight options available from Portland to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 2, 2026.