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$452+ 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 9/23. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LON
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
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 June 12, 2025.

Round-trip from

$708
(Delta)

One-way from

$452
(United Airlines)

Popular in

June

Cheapest in

October

Average price

$1,208
From Portland to London (LON)
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One-way flight from Portland to London (LON)
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Highest demand for flights based on searches. 18% potential increase in price ($190 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($33 potential savings vs. average RT price).
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Average for round-trip flights in June 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 June 12, 2025.

This Delta deal was found by Cheapflights users on 6/11. 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 8/122:36 pmPWM - LGW
1 stop14h 24mDelta
Wed 8/2012:00 pmLGW - PWM
1 stop17h 48mDelta
Deal found 6/11$708
This JetBlue deal was found by Cheapflights users on 6/10. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/126:10 amPWM - LHR
1 stop9h 35mJetBlue
Wed 8/2011:55 amLHR - PWM
1 stop16h 42mJetBlue
Deal found 6/10$722
This United Airlines deal was found by Cheapflights users on 6/10. 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 8/126:01 amPWM - LHR
1 stop9h 39mUnited Airlines
Wed 8/207:25 amLHR - PWM
2 stops20h 36mUnited Airlines
Deal found 6/10$735
This Delta deal was found by Cheapflights users on 6/10. 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 8/1212:53 pmPWM - LHR
2 stops16h 07mDelta
Wed 8/209:00 amLHR - PWM
2 stops20h 03mDelta
Deal found 6/10$747
This Air France deal was found by Cheapflights users on 6/10. 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 Air France is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/226:54 pmPWM - LHR
1 stop13h 36mMultiple Airlines
Tue 7/291:05 pmLHR - PWM
1 stop16h 33mMultiple Airlines
Deal found 6/10$792
This KLM deal was found by Cheapflights users on 6/10. 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.
Sun 9/142:35 pmPWM - LHR
1 stop13h 15mKLM
Sat 9/271:05 pmLHR - PWM
1 stop15h 58mKLM
Deal found 6/10$801
This Air Canada deal was found by Cheapflights users on 6/11. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/98:00 amPWM - LHR
3 stops17h 30mAir Canada
Wed 10/158:30 amLHR - PWM
3 stops19h 43mAir Canada
Deal found 6/11$814
This Scandinavian Airlines deal was found by Cheapflights users on 6/11. 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 Scandinavian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/192:35 pmPWM - LHR
3 stops23h 15mScandinavian Airlines
Mon 11/246:40 amLHR - PWM
2 stops21h 51mScandinavian Airlines
Deal found 6/11$831
This United Airlines deal was found by Cheapflights users on 6/11. 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.
Sat 11/223:00 pmPWM - LCY
2 stops16h 40mMultiple Airlines
Sun 11/307:20 pmLCY - PWM
2 stops27h 28mMultiple Airlines
Deal found 6/11$979
This Kiwi.com deal was found by Cheapflights users on 6/11. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/116:05 pmPWM - LGW
1 stop34h 55mMultiple Airlines
Fri 7/182:00 pmLGW - PWM
1 stop26h 53mMultiple Airlines
Deal found 6/11$987
This oojo deal was found by Cheapflights users on 6/11. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/97:09 amPWM - LGW
2 stops21h 46mTurkish Airlines
Wed 10/155:20 amLGW - PWM
2 stops21h 41mTurkish Airlines
Deal found 6/11$1,098
This FlightHub deal was found by Cheapflights users on 6/12. 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.
Thu 6/122:19 pmPWM - LHR
2 stops27h 06mTurkish Airlines
Mon 6/166:30 amLHR - PWM
2 stops22h 22mTurkish Airlines
Deal found 6/12$1,168

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 June 12, 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 - LGW

PWMLGW

Portland

Tue 8/12

2:36 pm-10:00 am

1 stop14h 24m

London Gatwick

Wed 8/20

12:00 pm-12:48 am

1 stop17h 48m

$708

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 8/12

6:10 am-8:45 pm

1 stop9h 35m

London Heathrow

Wed 8/20

11:55 am-11:37 pm

1 stop16h 42m

$722

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 8/12

6:01 am-8:40 pm

1 stop9h 39m

London Heathrow

Wed 8/20

7:25 am-11:01 pm

2 stops20h 36m

$735

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 8/12

12:53 pm-10:00 am

2 stops16h 07m

London Heathrow

Wed 8/20

9:00 am-12:03 am

2 stops20h 03m

$747

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 7/22

6:54 pm-1:30 pm

1 stop13h 36m

London Heathrow

Tue 7/29

1:05 pm-12:38 am

1 stop16h 33m

$792

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 9/14

2:35 pm-8:50 am

1 stop13h 15m

London Heathrow

Sat 9/27

1:05 pm-12:03 am

1 stop15h 58m

$801

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 10/9

8:00 am-6:30 am

3 stops17h 30m

London Heathrow

Wed 10/15

8:30 am-11:13 pm

3 stops19h 43m

$814

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 11/19

2:35 pm-6:50 pm

3 stops23h 15m

London Heathrow

Mon 11/24

6:40 am-11:31 pm

2 stops21h 51m

$831

PortlandLondon

PWM - LCY

PWMLCY

Portland

Sat 11/22

3:00 pm-12:40 pm

2 stops16h 40m

London City

Sun 11/30

7:20 pm-5:48 pm

2 stops27h 28m

$979

PortlandLondon

PWM - LGW

PWMLGW

Portland

Fri 7/11

6:05 pm-10:00 am

1 stop34h 55m

London Gatwick

Fri 7/18

2:00 pm-11:53 am

1 stop26h 53m

$987

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/10

Showing 1-10 of 23 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 $1,108). 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 June 12, 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.

Rainfall in London by month

Plan your trip to London by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in London 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 when rainfall is around 1.6 in.

Temperature in London by month

Plan your trip to London by taking into account the average temperature totals by month.

If weather is an important factor for your trip to London, 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).

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 June 12, 2025.
Read reviews from past customers who have flown Delta, KLM and Austrian Airlines from Portland to London. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,946 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Overall

8.0

Food

7.3

Crew

8.5

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
7,946 reviews
Delta
8.0
Very good
7,946 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Overall

8.0

Food

7.3

Crew

8.5

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!
KLM
7.8
Good
1,358 reviews
Delta
8.0
Very good
7,946 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Overall

8.0

Food

7.3

Crew

8.5

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!
Austrian Airlines
7.6
Good
802 reviews
Delta
8.0
Very good
7,946 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Overall

8.0

Food

7.3

Crew

8.5

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
8,790 reviews
Delta
8.0
Very good
7,946 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Overall

8.0

Food

7.3

Crew

8.5

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
7.3
Good
2,925 reviews
Delta
8.0
Very good
7,946 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Overall

8.0

Food

7.3

Crew

8.5

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.

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

    Flying on Delta is currently your cheapest option to London, with prices starting at $708. Additional round-trip tickets that might be worth considering are offered by JetBlue and United Airlines, with the lowest prices starting at $722 and $735, respectively. Delta is 16% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the cheapest airlines to fly from Portland, Maine to London one-way?

    To fly one-way, consider booking your trip with United Airlines, which is currently one of the cheapest options available, starting at $452. Scandinavian Airlines flights start at $2,236 while deals on JetBlue start at $2,488 one-way.

  • 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 $1,108). 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 Portland?

Book flights to Portland if you plan to visit one of these locations
Hayes
Hounslow
Thornton Heath
Luton
Canterbury
Harrow
Dover
Gatwick
Orpington
Watford
Croydon
Folkestone
Borehamwood
Sutton
Aylesbury
Chelmsford
Brentwood
Chichester
Wembley
Arundel

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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
JetBlueCheapest$586Average$678FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$665Average$886FlexibilityNo cancel feeOn-time69%
DeltaCheapest$825Average$963FlexibilityNo cancel feeOn-timeN/A

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