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Cheap flights from Portland, Maine to London from £248

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 10/12. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LON
17 Dec — 24 Dec1
1 adult
1 adult, Economy, 0 bags

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 17 November 2025.

Round-trip from

£467

One-way from

£248

Popular in

June

Cheapest in

October

Average price

£646
American Airlines
  • American Airlines
  • 1/12-9/12
  • 3 total stops
  • 27h 13m total
  • Portland to London
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10/12
  • 10/12
  • 3 total stops
  • 35h 37m total
  • Portland to London
Search Deals
Highest demand for flights based on searches. 17% potential increase in price (£106 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease (£20 potential savings vs. average return price).
Search Deals
Average for round-trip flights in November 2025
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Find flight deals from Portland to London

Enter your travel dates to find the best prices.

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 17 November 2025.

Mon 1/1217:37PWM - LHR
1 stop11h 48mAmerican Airlines
Tue 9/1207:50LHR - PWM
2 stops15h 25mAmerican Airlines
Deal found 15/11£467
Mon 1/1216:53PWM - LHR
2 stops15h 52mDelta
Tue 9/1208:40LHR - PWM
2 stops20h 19mDelta
Deal found 15/11£473
Sun 16/1106:00PWM - LHR
1 stop22h 00mVirgin Atlantic
Sun 23/1106:30LHR - PWM
2 stops20h 49mVirgin Atlantic
Deal found 15/11£508
Sun 16/1112:48PWM - LHR
2 stops17h 52mDelta
Sun 23/1108:40LHR - PWM
2 stops18h 39mDelta
Deal found 15/11£512
Sun 16/1116:53PWM - LHR
1 stop10h 52mKLM
Sun 23/1116:35LHR - PWM
1 stop12h 19mKLM
Deal found 15/11£530
Thu 11/1214:34PWM - LHR
1 stop11h 21mDelta
Fri 19/1213:05LHR - PWM
2 stops15h 16mDelta
Deal found 15/11£533
Thu 11/1206:00PWM - LHR
1 stop19h 35mAmerican Airlines
Mon 15/1207:50LHR - PWM
2 stops15h 25mAmerican Airlines
Deal found 16/11£544
Wed 31/1219:30PWM - LHR
1 stop10h 20mUnited Airlines
Wed 7/112:05LHR - PWM
2 stops16h 25mUnited Airlines
Deal found 16/11£546
Wed 31/1213:03PWM - LHR
1 stop14h 02mKLM
Wed 7/116:10LHR - PWM
1 stop13h 10mKLM
Deal found 16/11£560
Wed 31/1213:03PWM - LCY
2 stops15h 27mDelta
Wed 7/110:00LCY - PWM
2 stops19h 20mDelta
Deal found 16/11£686
Mon 1/1209:46PWM - LGW
1 stop19h 14mMultiple Airlines
Tue 9/1211:40LGW - PWM
2 stops52h 38mMultiple Airlines
Deal found 15/11£979
Thu 11/1211:58PWM - LGW
2 stops40h 47mMultiple Airlines
Thu 18/1214:00LGW - PWM
1 stop24h 06mMultiple Airlines
Deal found 15/11£1,305

Cheapflights Fare Finder

 
Customise 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 858,174 searches. Data last updated 17 November 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

Sat 7/2

14:35-08:05

1 stop12h 30m

London Heathrow

Sat 14/2

08:55-23:04

1 stop19h 09m

£496

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 7/2

12:48-09:00

2 stops15h 12m

London Heathrow

Sat 14/2

08:55-23:04

1 stop19h 09m

£500

PortlandLondon

PWM - LCY

PWMLCY

Portland

Fri 23/1

06:17-08:10

2 stops20h 53m

London City

Tue 27/1

08:40-00:20

2 stops20h 40m

£502

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 7/2

14:31-07:10

2 stops35h 39m

London Heathrow

Sat 14/2

11:05-18:56

2 stops36h 51m

£523

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 11/12

06:00-06:35

1 stop19h 35m

London Heathrow

Mon 15/12

07:50-18:15

2 stops15h 25m

£544

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 31/12

19:30-10:50

1 stop10h 20m

London Heathrow

Wed 7/1

12:05-23:30

2 stops16h 25m

£546

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 27/3

14:35-09:20

2 stops14h 45m

London Heathrow

Tue 31/3

10:35-23:49

2 stops42h 14m

£642

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 1/1

13:03-06:20

1 stop12h 17m

London Heathrow

Thu 8/1

08:55-22:27

1 stop18h 32m

£642

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 10/5

06:00-06:30

2 stops19h 30m

London Heathrow

Sat 16/5

16:25-10:44

2 stops47h 19m

£651

PortlandLondon

PWM - LCY

PWMLCY

Portland

Wed 31/12

13:03-09:30

2 stops15h 27m

London City

Wed 7/1

10:00-00:20

2 stops19h 20m

£686

Flights are sorted by cheapest return flights first.

Deals found on 16/11

Showing 1-10 of 26 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 return 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 £236). Flying from Portland, Maine to London in June is currently the most expensive (average of £426). 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’s the top stopover airport for flights from Portland, Maine to London?

Share of one-stop return flights from Portland, Maine to London chosen by Cheapflights users in the past 12 months, using the same stopover each way.

Newark (EWR) – chosen by Cheapflights users on 40% of one-stop itineraries from Portland, Maine to London on Cheapflights.

What’s the cheapest stopover airport for flights from Portland, Maine to London?

Average return fare for one-stop flights from Portland, Maine to London, chosen by Cheapflights users in the past 12 months, with the same stopover each way.

New York (JFK) is the most affordable one-stop option, with an average return flight price of £488.

What’s the fastest stopover option from Portland, Maine to London?

Shortest average travel time for one-stop one-way flights from Portland, Maine to London, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by stopover airport.

Flights via Newark (EWR) have the shortest average one-way travel time for one-stop routes: 9h 40m.

Which airport typically offers the quickest stopover for flights from Portland, Maine to London?

Average stopover duration for one-stop one-way flights from Portland, Maine to London, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Newark (EWR) offer the fastest connection on this route, with an average stopover time of 1h 35m.

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 0 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 10h 20m. Fly via Delta, American Airlines, or United Airlines to get the fastest option. The distance between Portland, Maine and London is about 3173 mi. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

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

    The most popular flight routes from Portland, Maine to London are Portland - London Heathrow, Portland - London Gatwick and Portland - London City.

  • 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 holiday 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 £236). Flying from Portland, Maine to London in June is currently the most expensive (average of £426). 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

Travelling to a place near London?

Book flights to London if you plan to visit one of these locations
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Why should you use Cheapflights to find cheap flight tickets from Portland to London?

Cheapflights helps you find that perfect flight to London from Portland by searching from hundreds of airlines and agencies you know and love. We are also free to use, in case you were wondering!

Can Cheapflights find flights from Portland to London with no change fees?

Certainly. Search results for flights to London from Portland shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

Can Cheapflights notify me if prices for flights from Portland to London become cheaper?

Yes, Cheapflights offers price alerts on Portland to London flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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