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Heathrow

$622+ 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 12/1. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
dic. 3 — dic. 101
mié. 12/3
mié. 12/10
1 adult, Economy
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Cheap flight deals from Portland to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from Portland (PWM) 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 noviembre 3, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$584
(Delta)

Popular in

June

Cheapest in

May

Average price

$799
Provider with most accurate pricing for Portland-London Heathrow flight deals.
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Provider most trusted by Cheapflights users for Portland-London Heathrow flights.
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From Portland to London Heathrow
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Highest demand for flights based on searches. 10% potential increase in price ($119 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($44 potential savings vs. average RT price).
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Average for round-trip flights in November 2025
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Find 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 noviembre 3, 2025.

This KLM deal was found by Cheapflights users on 11/2. 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.
lun. 12/14:53 pmPWM - LHR
1 stop10h 52mKLM
dom. 12/1410:45 amLHR - PWM
1 stop16h 38mKLM
Deal found 11/2$622
This Delta deal was found by Cheapflights users on 11/2. 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.
dom. 11/96:35 amPWM - LHR
1 stop18h 45mDelta
dom. 11/168:40 amLHR - PWM
2 stops20h 14mDelta
Deal found 11/2$641
This Virgin Atlantic deal was found by Cheapflights users on 11/2. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 11/96:00 amPWM - LHR
1 stop22h 00mVirgin Atlantic
dom. 11/1610:45 amLHR - PWM
1 stop16h 34mVirgin Atlantic
Deal found 11/2$647
This Booking.com deal was found by Cheapflights users on 11/2. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/17:44 pmPWM - LHR
2 stops30h 26mAir Canada
dom. 12/141:25 pmLHR - PWM
2 stops34h 17mAir Canada
Deal found 11/2$674
This United deal was found by Cheapflights users on 11/2. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/14:52 pmPWM - LHR
1 stop13h 23mMultiple Airlines
dom. 12/141:25 pmLHR - PWM
2 stops24h 45mMultiple Airlines
Deal found 11/2$697
This United deal was found by Cheapflights users on 11/2. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 11/96:00 amPWM - LHR
2 stops23h 05mMultiple Airlines
dom. 11/161:25 pmLHR - PWM
2 stops24h 54mMultiple Airlines
Deal found 11/2$705
This Delta deal was found by Cheapflights users on 11/1. 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.
mar. 12/162:34 pmPWM - LHR
2 stops18h 16mDelta
mar. 12/238:00 pmLHR - PWM
1 stop21h 20mDelta
Deal found 11/1$733
This deal was found by Cheapflights users on 11/2. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 11/186:00 amPWM - LHR
1 stop10h 20mUnited Airlines
mar. 11/259:10 amLHR - PWM
1 stop13h 48mUnited Airlines
Deal found 11/2$747
This United Airlines deal was found by Cheapflights users on 11/1. 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.
mar. 12/163:00 pmPWM - LHR
1 stop10h 20mUnited Airlines
mar. 12/233:10 pmLHR - PWM
1 stop13h 12mUnited Airlines
Deal found 11/1$782
This FlightHub deal was found by Cheapflights users on 11/1. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 11/96:35 amPWM - LHR
2 stops28h 25mScandinavian Airlines
mié. 11/126:40 amLHR - PWM
2 stops22h 14mScandinavian Airlines
Deal found 11/1$789

Cheapflights Fare Finder

 
Customize your flight search to find flights from Portland 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 noviembre 3, 2025.
Use the filters below to find and compare flights from Portland to London Heathrow Airport that are best for you.

Fly from

Portland

Fly to

Heathrow

Route

Depart

Return

Price

PortlandLondon

PWM - LHR

PWMLHR

Portland

lun. 12/1

4:53 pm-8:45 am

1 stop10h 52m

London Heathrow

dom. 12/14

10:45 am-10:23 pm

1 stop16h 38m

$622

PortlandLondon

PWM - LHR

PWMLHR

Portland

vie. 2/6

2:35 pm-8:05 am

1 stop12h 30m

London Heathrow

dom. 2/8

4:35 pm-12:20 am

1 stop12h 45m

$656

PortlandLondon

PWM - LHR

PWMLHR

Portland

lun. 12/1

7:44 pm-7:10 am

2 stops30h 26m

London Heathrow

dom. 12/14

1:25 pm-6:42 pm

2 stops34h 17m

$674

PortlandLondon

PWM - LHR

PWMLHR

Portland

jue. 2/26

2:35 pm-8:05 am

1 stop12h 30m

London Heathrow

jue. 3/19

11:45 am-11:49 pm

2 stops16h 04m

$677

PortlandLondon

PWM - LHR

PWMLHR

Portland

jue. 2/26

2:35 pm-1:45 pm

2 stops18h 10m

London Heathrow

jue. 3/19

11:45 am-11:49 pm

2 stops16h 04m

$682

PortlandLondon

PWM - LHR

PWMLHR

Portland

lun. 12/1

4:52 pm-11:15 am

1 stop13h 23m

London Heathrow

dom. 12/14

1:25 pm-9:10 am

2 stops24h 45m

$697

PortlandLondon

PWM - LHR

PWMLHR

Portland

mar. 12/16

2:34 pm-1:50 pm

2 stops18h 16m

London Heathrow

mar. 12/23

8:00 pm-12:20 pm

1 stop21h 20m

$733

PortlandLondon

PWM - LHR

PWMLHR

Portland

vie. 3/27

6:30 am-8:10 pm

1 stop9h 40m

London Heathrow

mar. 3/31

11:45 am-11:49 pm

2 stops17h 04m

$776

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/2

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 November.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust 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 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, February is the cheapest month in which you can book a flight from Portland, Maine to London Heathrow Airport (average of $361). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of $595). 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 PWM to LHR?

Find hourly flight availability from Portland 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 noviembre 3, 2025.

It’s typically best to fly out from Portland, Maine to London Heathrow Airport in the evening. Doing so could potentially save you 11% on the flight price compared to flying in the morning, which is usually more expensive.

How much does it cost to fly round-trip from Portland, Maine to London Heathrow Airport?

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 noviembre 3, 2025.
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
8,002 reviews

Entertainment

7.9

Food

7.3

Crew

8.5

Overall

7.9

Boarding

8.2

Comfort

7.9

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
8,002 reviews
Delta
7.9
Good
8,002 reviews

Entertainment

7.9

Food

7.3

Crew

8.5

Overall

7.9

Boarding

8.2

Comfort

7.9

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.
United Airlines
7.4
Good
8,997 reviews
Delta
7.9
Good
8,002 reviews

Entertainment

7.9

Food

7.3

Crew

8.5

Overall

7.9

Boarding

8.2

Comfort

7.9

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.

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?

    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 10h 52m. Fly via KLM, Air Canada, or Delta 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, February is the cheapest month in which you can book a flight from Portland, Maine to London Heathrow Airport (average of $361). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of $595). 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 London Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Hounslow
Ilford
Hayes
Southend-on-Sea
Harrow
Croydon
Eastleigh
Dartford
Dover
Winchester
Orpington
Northampton
Gatwick
Borehamwood
Broadway
Aylesbury
Bedford
Chipping Norton
Wembley
Folkestone

Browse thousands of different options on Cheapflights for your next trip

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Top 2 airlines flying from Portland to Heathrow

Discover the top 2 airlines that operate flights from Portland 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 noviembre 3, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$648Average$924FlexibilityNo cancel feeOn-time69%
DeltaCheapest$825Average$963FlexibilityNo cancel feeOn-timeN/A

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