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$524+ Cheap flights from Portland, ME (PWM) to London (LON)

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 9/24. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LON
Oct 17 — Oct 241
Fri 10/17
Fri 10/24
1 adult, Economy
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Cheap 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 September 17, 2025.

Round-trip from

$524
(Virgin Atlantic)

Popular in

July

Cheapest in

October

Average price

$790
From Portland to London (LON)
Search Deals
Highest demand for flights based on searches. 16% potential increase in price ($173 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($32 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in September 2025
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Find flight deals from Portland to London

Cheapest flights from Portland to London
Explore the most affordable flight options available from Portland to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 17, 2025.

This Virgin Atlantic deal was found by Cheapflights users on 9/15. 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 11/121:25 pmPWM - LHR
1 stop13h 25mVirgin Atlantic
Thu 11/209:00 amLHR - PWM
2 stops18h 19mVirgin Atlantic
Deal found 9/15$524
This Delta deal was found by Cheapflights users on 9/17. 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 11/116:00 amPWM - LHR
1 stop19h 25mDelta
Fri 11/216:20 amLHR - PWM
2 stops22h 34mDelta
Deal found 9/17$525
This Delta deal was found by Cheapflights users on 9/17. 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.
Mon 11/102:30 pmPWM - LHR
1 stop12h 35mDelta
Tue 11/1810:00 amLHR - PWM
2 stops18h 54mDelta
Deal found 9/17$526
This Delta deal was found by Cheapflights users on 9/15. 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 9/245:00 pmPWM - LHR
2 stops15h 30mDelta
Tue 9/309:00 amLHR - PWM
2 stops20h 34mDelta
Deal found 9/15$528
This Delta deal was found by Cheapflights users on 9/15. 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 11/1112:48 pmPWM - LHR
2 stops15h 32mDelta
Wed 11/1911:30 amLHR - PWM
2 stops17h 24mDelta
Deal found 9/15$529
This Delta deal was found by Cheapflights users on 9/15. 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 11/1112:48 pmPWM - LHR
2 stops15h 32mDelta
Thu 11/2011:45 amLHR - PWM
2 stops17h 09mDelta
Deal found 9/15$530
This KLM deal was found by Cheapflights users on 9/15. 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 11/114:53 pmPWM - LHR
1 stop10h 52mKLM
Fri 11/218:55 amLHR - PWM
1 stop18h 24mKLM
Deal found 9/15$532
This Delta deal was found by Cheapflights users on 9/17. 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.
Mon 11/102:30 pmPWM - LHR
1 stop10h 50mDelta
Thu 11/202:30 pmLHR - PWM
1 stop14h 24mDelta
Deal found 9/17$533
This Delta deal was found by Cheapflights users on 9/14. 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 10/152:38 pmPWM - LHR
2 stops15h 07mDelta
Fri 10/246:30 amLHR - PWM
2 stops22h 35mDelta
Deal found 9/14$557
This Delta deal was found by Cheapflights users on 9/15. 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 10/301:27 pmPWM - LHR
1 stop12h 58mDelta
Thu 11/66:20 amLHR - PWM
2 stops22h 45mDelta
Deal found 9/15$574
This Delta deal was found by Cheapflights users on 9/17. 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.
Fri 11/141:25 pmPWM - LHR
1 stop13h 25mDelta
Tue 11/189:00 amLHR - PWM
2 stops19h 54mDelta
Deal found 9/17$575
This Delta deal was found by Cheapflights users on 9/15. 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 11/112:30 pmPWM - LCY
2 stops12h 40mDelta
Fri 11/219:20 amLCY - PWM
2 stops19h 34mDelta
Deal found 9/15$582

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 September 17, 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 11/12

1:25 pm-7:50 am

1 stop13h 25m

London Heathrow

Wed 11/19

11:30 am-11:54 pm

2 stops17h 24m

$524

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 11/12

1:25 pm-7:50 am

1 stop13h 25m

London Heathrow

Thu 11/20

9:00 am-10:19 pm

2 stops18h 19m

$524

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/11

2:30 pm-9:35 am

1 stop14h 05m

London Heathrow

Wed 11/19

8:55 am-10:19 pm

2 stops18h 24m

$524

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 11/10

6:35 am-10:15 am

1 stop22h 40m

London Heathrow

Wed 11/19

9:00 am-11:54 pm

2 stops19h 54m

$525

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 11/10

2:30 pm-10:15 am

1 stop14h 45m

London Heathrow

Thu 11/20

6:20 am-11:54 pm

2 stops22h 34m

$525

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 11/12

2:30 pm-8:05 am

1 stop12h 35m

London Heathrow

Fri 11/21

11:45 am-11:54 pm

2 stops17h 09m

$525

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 11/10

2:30 pm-10:15 am

1 stop14h 45m

London Heathrow

Fri 11/21

6:20 am-11:54 pm

2 stops22h 34m

$525

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 10/15

2:38 pm-11:25 am

1 stop15h 47m

London Heathrow

Fri 10/24

6:30 am-12:05 am

2 stops22h 35m

$525

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/11

12:48 pm-9:20 am

2 stops15h 32m

London Heathrow

Fri 11/21

11:45 am-11:54 pm

2 stops17h 09m

$530

PortlandLondon

PWM - LCY

PWMLCY

Portland

Wed 11/12

2:30 pm-7:15 am

2 stops11h 45m

London City

Fri 11/21

9:20 am-11:54 pm

2 stops19h 34m

$582

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 31 results
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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, November is the cheapest month in which you can book a flight from Portland, Maine to London (average of $661). Flying from Portland, Maine to London in June is currently the most expensive (average of $1,097). 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 September 17, 2025.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 5% on flights from Portland, Maine to London by exploring options for tickets at noon.

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 September 17, 2025.
Get a feel of what it's like to fly with Delta, United Airlines, and American Airlines 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
8.0
Very good
7,961 reviews

Entertainment

7.9

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

Food

7.3

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
7,961 reviews
Delta
8.0
Very good
7,961 reviews

Entertainment

7.9

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

Food

7.3

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
8,926 reviews
Delta
8.0
Very good
7,961 reviews

Entertainment

7.9

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

Food

7.3

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!
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,961 reviews

Entertainment

7.9

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

Food

7.3

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!
JetBlue
7.2
Good
2,914 reviews
Delta
8.0
Very good
7,961 reviews

Entertainment

7.9

Overall

8.0

Boarding

8.2

Comfort

7.9

Crew

8.5

Food

7.3

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

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 3 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 13h 25m. Fly via Delta or Virgin Atlantic to get the fastest option. There are 3173 mi between Portland, Maine and London.

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

    Flying on JetBlue is currently your cheapest option to London, with prices starting at $586. Additional round-trip tickets that might be worth considering are offered by United Airlines and Delta, with the lowest prices starting at $648 and $825, respectively. JetBlue is 33% 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, November is the cheapest month in which you can book a flight from Portland, Maine to London (average of $661). Flying from Portland, Maine to London in June is currently the most expensive (average of $1,097). 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
Hounslow
Hayes
Southend-on-Sea
Harrow
Canterbury
Croydon
Eastleigh
Dartford
Dover
Winchester
Orpington
Gatwick
Borehamwood
Aylesbury
Bedford
Wembley
Folkestone
Chichester
Eastbourne
Sutton

Browse thousands of different options on Cheapflights for your next trip

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Top 3 airlines flying from Portland to London

Discover the top 3 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 September 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
JetBlueCheapest$586Average$678FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$648Average$853FlexibilityNo cancel feeOn-time69%
DeltaCheapest$825Average$963FlexibilityNo cancel feeOn-timeN/A

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