Cheap flights from Portland, Maine to London from £244

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 17/8. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LON
11 Jun — 18 Jun1
1 adult
1 adult, Economy, 0 bags

Cheap 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 12 May 2026.

Sun 10/514:38
PWM
-
LHR
1 stop11h 37m
Delta
Sat 16/508:40
LHR
-
PWM
2 stops21h 03m
Delta
Deal found 7/5£641
Tue 10/1113:35
PWM
-
LHR
1 stop11h 50m
Delta
Tue 17/1106:30
LHR
-
PWM
2 stops20h 53m
Delta
Deal found 11/5£642
Wed 12/814:53
PWM
-
LHR
1 stop16h 12m
Delta
Thu 20/808:55
LHR
-
PWM
2 stops21h 04m
Delta
Deal found 8/5£647
Thu 3/914:35
PWM
-
LHR
2 stops18h 15m
Delta
Mon 7/909:55
LHR
-
PWM
2 stops17h 38m
Delta
Deal found 11/5£649
Tue 27/1013:35
PWM
-
LHR
2 stops15h 25m
Virgin Atlantic
Mon 2/1106:30
LHR
-
PWM
2 stops20h 53m
Virgin Atlantic
Deal found 11/5£650
Sun 10/507:20
PWM
-
LHR
1 stop21h 10m
JetBlue
Sat 16/508:15
LHR
-
PWM
1 stop19h 48m
JetBlue
Deal found 7/5£661
Sat 9/507:20
PWM
-
LHR
1 stop21h 10m
JetBlue
Wed 20/511:55
LHR
-
PWM
1 stop16h 08m
JetBlue
Deal found 8/5£662
Tue 10/1115:15
PWM
-
LHR
2 stops13h 50m
United Airlines
Tue 17/1106:50
LHR
-
PWM
2 stops14h 19m
United Airlines
Deal found 11/5£664
Tue 18/806:00
PWM
-
LHR
2 stops19h 30m
Air Canada
Fri 21/814:05
LHR
-
PWM
2 stops33h 24m
Air Canada
Deal found 8/5£667
Thu 3/914:35
PWM
-
LCY
2 stops13h 55m
Delta
Mon 7/908:25
LCY
-
PWM
2 stops19h 08m
Delta
Deal found 11/5£701
Sat 6/617:01
PWM
-
LGW
2 stops35h 59m
Multiple Airlines
Fri 12/614:00
LGW
-
PWM
1 stop24h 12m
Multiple Airlines
Deal found 8/5£709
Fri 3/714:59
PWM
-
LGW
2 stops13h 26m
Delta
Wed 8/710:25
LGW
-
PWM
2 stops17h 49m
Delta
Deal found 11/5£791

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 12 May 2026.

Round-trip from

£642

One-way from

£244

Popular in

July

Cheapest in

October

Average price

£540
Virgin Atlantic
  • Virgin Atlantic
  • 27/10-2/11
  • 3 total stops
  • 43h 53m total
  • Portland to London
American Airlines
  • American Airlines
  • 17/8
  • 1 total stop
  • 14h 54m total
  • Portland to London
Highest demand for flights based on searches. 22% potential increase in price (£130 potential increase over avg. return price).
Cheapest flight prices on average. 6% potential price decrease (£29 potential savings vs. average return price).
Average for round-trip flights in May 2026

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 12 May 2026.
Use the filters below to find and compare flights from Portland to London that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight
Fastest return journey

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 27/10

13:35-07:50

1 stop14h 15m

London Heathrow

Mon 2/11

16:10-23:49

1 stop12h 39m

£664

PortlandLondon

PWM - LCY

PWMLCY

Portland

Thu 3/9

14:35-09:30

2 stops13h 55m

London City

Mon 7/9

08:25-22:33

2 stops19h 08m

£701

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 25/6

18:57-13:15

1 stop13h 18m

London Heathrow

Mon 29/6

11:45-00:52

2 stops18h 07m

£782

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 22/6

12:40-07:10

1 stop13h 30m

London Heathrow

Mon 29/6

11:45-00:52

2 stops18h 07m

£782

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 9/6

14:59-10:20

1 stop14h 21m

London Heathrow

Tue 16/6

09:55-00:52

2 stops19h 57m

£785

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 28/5

14:38-10:20

1 stop14h 42m

London Heathrow

Sun 31/5

08:40-23:09

2 stops19h 29m

£785

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 3/7

16:45-13:05

2 stops15h 20m

London Heathrow

Wed 8/7

11:45-00:59

2 stops18h 14m

£786

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 6/6

06:00-21:25

1 stop10h 25m

London Heathrow

Fri 12/6

06:50-19:27

2 stops17h 37m

£787

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 4/7

06:00-20:40

1 stop9h 40m

London Heathrow

Fri 10/7

06:50-23:30

2 stops21h 40m

£787

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 11/6

14:59-13:45

2 stops17h 46m

London Heathrow

Tue 16/6

09:55-23:05

2 stops18h 10m

£789

Flights are sorted by cheapest return flights first.

Deals found on 9/5

Showing 1-10 of 55 resultsSorted by cheapest first
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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

How much does it cost for a return flight from Portland, Maine to London?

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 33% 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 £425.

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 24m.

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 13h 55m. Fly via KLM or Delta to get the fastest option. The distance between Portland, Maine and London is about 3193 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?

  • 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.

See more FAQs

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How does Cheapflights help users find flights from Portland to London?

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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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