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$503+ Cheap flights from Portland, ME (PWM) to London (LON)

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 2/12. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LON
Jan 22 — Jan 291
Thu 1/22
Thu 1/29
1 adult, Economy
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Cheap flight deals from Portland to London

Best flights from Portland to London
Discover carefully curated flight deals from Portland to London that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated December 23, 2025.

This Virgin Atlantic deal was found by Cheapflights users on 12/21. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/45:30 amPWM - LHR
1 stop22h 30mVirgin Atlantic
Wed 2/116:30 amLHR - PWM
2 stops20h 57mVirgin Atlantic
Deal found 12/21$629
This Delta deal was found by Cheapflights users on 12/22. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/312:30 pmPWM - LHR
1 stop14h 45mDelta
Tue 4/148:40 amLHR - PWM
2 stops21h 06mDelta
Deal found 12/22$645
This KLM deal was found by Cheapflights users on 12/21. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/42:35 pmPWM - LHR
1 stop14h 40mKLM
Wed 2/1112:40 pmLHR - PWM
1 stop16h 40mKLM
Deal found 12/21$657
This Cheapflightsfares deal was found by Cheapflights users on 12/21. 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.
Wed 2/411:10 amPWM - LHR
1 stop17h 00mAustrian Airlines
Wed 2/116:00 amLHR - PWM
2 stops22h 21mAustrian Airlines
Deal found 12/21$684
This United Airlines deal was found by Cheapflights users on 12/21. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 1/207:27 pmPWM - LHR
1 stop10h 38mUnited Airlines
Thu 1/296:50 amLHR - PWM
2 stops17h 00mUnited Airlines
Deal found 12/21$691
This FlightHub deal was found by Cheapflights users on 12/22. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/316:00 amPWM - LGW
2 stops26h 10mTurkish Airlines
Tue 4/147:00 amLGW - PWM
2 stops21h 36mTurkish Airlines
Deal found 12/22$1,024
This American Airlines deal was found by Cheapflights users on 12/23. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/113:58 pmPWM - LCY
2 stops15h 42mMultiple Airlines
Mon 2/166:50 amLCY - PWM
2 stops16h 13mMultiple Airlines
Deal found 12/23$1,208
This Delta deal was found by Cheapflights users on 12/21. 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 4/14:48 pmPWM - LHR
2 stops15h 42mDelta
Wed 4/158:40 amLHR - PWM
2 stops21h 06mDelta
Deal found 12/21$649
This KLM deal was found by Cheapflights users on 12/21. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/312:30 pmPWM - LHR
1 stop14h 45mKLM
Tue 4/1411:15 amLHR - PWM
1 stop17h 08mKLM
Deal found 12/21$673
This United Airlines deal was found by Cheapflights users on 12/21. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/411:10 amPWM - LHR
2 stops15h 45mUnited Airlines
Wed 2/1112:05 pmLHR - PWM
2 stops16h 16mUnited Airlines
Deal found 12/21$696
This Turkish Airlines deal was found by Cheapflights users on 12/21. 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 Turkish Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/16:00 amPWM - LGW
2 stops29h 20mTurkish Airlines
Wed 4/155:15 pmLGW - PWM
2 stops35h 21mTurkish Airlines
Deal found 12/21$1,657
This Icelandair deal was found by Cheapflights users on 12/22. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 2/153:55 pmPWM - LGW
2 stops14h 00mMultiple Airlines
Sat 2/2111:55 amLGW - PWM
2 stops16h 10mMultiple Airlines
Deal found 12/22$3,288
This Icelandair deal was found by Cheapflights users on 12/21. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/412:45 pmPWM - LGW
2 stops17h 10mMultiple Airlines
Wed 2/1111:55 amLGW - PWM
2 stops15h 20mMultiple Airlines
Deal found 12/21$3,312
This Delta deal was found by Cheapflights users on 12/23. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/122:35 pmPWM - LCY
2 stops13h 55mDelta
Tue 2/179:20 amLCY - PWM
2 stops18h 46mDelta
Deal found 12/23$5,108
This Delta deal was found by Cheapflights users on 12/23. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/122:35 pmPWM - LCY
2 stops13h 55mDelta
Fri 2/209:20 amLCY - PWM
2 stops19h 58mDelta
Deal found 12/23$5,343
This Delta deal was found by Cheapflights users on 12/22. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 2/152:35 pmPWM - LCY
2 stops12h 35mDelta
Sat 2/218:40 amLCY - PWM
2 stops20h 38mDelta
Deal found 12/22$9,033

Find flight deals from Portland to London

Discover tips and strategies to find the most affordable flight options for your journey from Portland (PWM) to London (LON). 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 December 23, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$629
(Virgin Atlantic)

One-way from

$503
(Delta)

Popular in

June

Cheapest in

October

Average price

$699
Provider with most accurate pricing for Portland-London (LON) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Portland-London (LON) flights.
Search Deals
From Portland to London (LON)
Search Deals
One-way flight from Portland to London (LON)
Search Deals
Highest demand for flights based on searches. 17% potential increase in price ($181 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($32 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Portland to London 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 December 23, 2025.
Use the filters below to find and compare flights from Portland to London that are best for you.

Fly from

Portland

Fly to

London

Route

Depart

Return

Price

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 2/4

5:30 am-9:00 am

1 stop22h 30m

London Heathrow

Wed 2/11

6:30 am-10:27 pm

2 stops20h 57m

$629

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 3/31

2:30 pm-10:15 am

1 stop14h 45m

London Heathrow

Tue 4/14

8:40 am-12:46 am

2 stops21h 06m

$645

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 4/1

4:48 pm-1:30 pm

2 stops15h 42m

London Heathrow

Wed 4/15

8:40 am-12:46 am

2 stops21h 06m

$649

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 2/4

2:35 pm-10:15 am

1 stop14h 40m

London Heathrow

Wed 2/11

12:40 pm-12:20 am

1 stop16h 40m

$657

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 3/31

2:30 pm-10:15 am

1 stop14h 45m

London Heathrow

Tue 4/14

11:15 am-11:23 pm

1 stop17h 08m

$673

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 2/4

11:10 am-9:10 am

1 stop17h 00m

London Heathrow

Wed 2/11

6:00 am-11:21 pm

2 stops22h 21m

$684

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 1/20

7:27 pm-11:05 am

1 stop10h 38m

London Heathrow

Thu 1/29

6:50 am-6:50 pm

2 stops17h 00m

$691

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 2/4

11:10 am-7:55 am

2 stops15h 45m

London Heathrow

Wed 2/11

12:05 pm-11:21 pm

2 stops16h 16m

$696

PortlandLondon

PWM - LGW

PWMLGW

Portland

Tue 3/31

6:00 am-1:10 pm

2 stops26h 10m

London Gatwick

Tue 4/14

7:00 am-11:36 pm

2 stops21h 36m

$1,024

PortlandLondon

PWM - LCY

PWMLCY

Portland

Wed 2/11

3:58 pm-12:40 pm

2 stops15h 42m

London City

Mon 2/16

6:50 am-6:03 pm

2 stops16h 13m

$1,208

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/23

Showing 1-10 of 45 results
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Compare providers for flights from Portland to London

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 London in December.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*3 stars
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 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 flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Portland, Maine-London flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Portland, Maine-London 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 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 London

Have a flexible travel schedule? Discover the best time to fly to London 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

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

Currently, August is the cheapest month in which you can book a flight from Portland, Maine to London (average of $311). Flying from Portland, Maine to London in June is currently the most expensive (average of $561). 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 LON?

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

Unlike at noon, when flights are generally more expensive, you can save up to 31% on flights from Portland, Maine to London by exploring options for tickets in the afternoon.

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

Reviews of airlines servicing London

Get insights into the airlines that provide service to London. 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 London. Reviews last updated December 23, 2025.
Get a feel of what it's like to fly with Delta, United Airlines, and JetBlue from Portland to London by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
8,015 reviews

Overall

7.9

Food

7.3

Entertainment

7.9

Comfort

7.9

Crew

8.5

Boarding

8.1

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
8,015 reviews
Delta
7.9
Good
8,015 reviews

Overall

7.9

Food

7.3

Entertainment

7.9

Comfort

7.9

Crew

8.5

Boarding

8.1

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
9,109 reviews
Delta
7.9
Good
8,015 reviews

Overall

7.9

Food

7.3

Entertainment

7.9

Comfort

7.9

Crew

8.5

Boarding

8.1

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.
JetBlue
7.2
Good
2,898 reviews
Delta
7.9
Good
8,015 reviews

Overall

7.9

Food

7.3

Entertainment

7.9

Comfort

7.9

Crew

8.5

Boarding

8.1

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 London. 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?

    Portland (PWM) is the airport you will fly out of if you book a flight from Portland to London. You should not have trouble finding flights to London from Portland; the airport handles an average of 0 outbound flights to London per day. You should also have plenty of airline options to choose from since 2 airlines have flights from the Portland airport to London. 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?

    There are many flights that can get you from Portland, Maine to London in 14h 45m. Fly via Virgin Atlantic, Delta, or Turkish Airlines to get the fastest option. There are 3173 mi between Portland, Maine and London. This flight may include one or multiple stops.

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

    Flying on United Airlines is currently your cheapest option to London, with prices starting at $648. Another option worth looking into is Delta, starting at $765 round trip. United Airlines is 24% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the most popular routes from Portland, Maine to London?

    Most travelers choose Portland - London Heathrow, Portland - London Gatwick or Portland - London City when deciding on the best route from Portland, Maine to London.

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

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

  • How can I find direct flights from Portland to London?

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

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

    Yes. Cheapflights offers flight deals from Portland to London 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?

    Currently, August is the cheapest month in which you can book a flight from Portland, Maine to London (average of $311). Flying from Portland, Maine to London in June is currently the most expensive (average of $561). 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?

Book flights to London if you plan to visit one of these locations
Ilford
Hounslow
Southend-on-Sea
Harrow
Eastleigh
Dartford
Dover
Winchester
Croydon
Hayes
Orpington
Watford
Borehamwood
Aylesbury
Chipping Norton
Horley
Kingston upon Thames
Folkestone
Eastbourne
Sutton

Browse thousands of different options on Cheapflights for your next trip

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Top 2 airlines flying from Portland to London

Discover the top 2 airlines that operate flights from Portland to London. 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 December 23, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$648Average$874FlexibilityNo cancel feeOn-time69%
DeltaCheapest$765Average$1,083FlexibilityNo cancel feeOn-timeN/A

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