Find flights
When to book
FAQs

Cheap flights from Portland, Maine to London from £242

PWM — LON
3 Nov — 10 Nov1
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

Mon 16/1114:05 -
1 stop15h 45m
Wed 18/1109:00 -
2 stops19h 21m
Deal found 29/9£555
Mon 9/1108:49 -
2 stops41h 21m
Thu 12/1106:50 -
2 stops21h 31m
Deal found 30/9£558
Sun 1/1117:08 -
1 stop33h 47m
Wed 4/1106:50 -
2 stops21h 31m
Deal found 1/10£559
Wed 11/1115:40 -
2 stops34h 30m
Sat 14/1106:50 -
2 stops17h 12m
Deal found 2/10£562
Mon 16/1116:03 -
1 stop13h 27m
Mon 23/1108:40 -
2 stops20h 39m
Deal found 2/10£645
Wed 28/1014:05 -
1 stop16h 45m
Wed 4/1112:05 -
2 stops16h 16m
Deal found 30/9£650
Tue 6/1012:42 -
1 stop13h 28m
Tue 20/1011:45 -
2 stops17h 25m
Deal found 30/9£651
Sat 31/1014:33 -
1 stop12h 42m
Sat 7/1106:30 -
2 stops19h 30m
Deal found 3/10£652

Find flight deals from Portland to London

Round-trip from

£555

One-way from

£242

Popular in

July

Cheapest in

February

Average price

£708
United Airlines
  • United Airlines
  • 16/11-18/11
  • 3 total stops
  • 35h 06m total
  • Portland to London
Search Deals
JetBlue
  • JetBlue
  • 23/10-31/12
  • 1 total stop
  • 9h 45m total
  • Portland to London
Search Deals
Highest demand for flights based on searches. 17% potential increase in price (£104 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease (£25 potential savings vs. average return price).
Search Deals
Average for round-trip flights in October 2026
Search Deals

Cheapflights Fare Finder

 
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

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Sun 8/11

06:00-06:35

1 stop19h 35m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£248

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Sun 8/11

08:47-10:50

2 stops21h 03m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£248

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Fri 23/10

06:00-05:55

2 stops18h 55m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£248
Fastest return journey

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Mon 12/10

16:15-08:50

1 stop11h 35m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£251

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Fri 23/10

08:03-06:30

3 stops17h 27m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£313

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Mon 16/11

14:05-10:50

1 stop15h 45m

London Heathrow

Wed 18/11

09:00-23:21

2 stops19h 21m

£555

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Wed 18/11

17:08-12:00

1 stop13h 52m

London Heathrow

Wed 25/11

06:50-23:21

2 stops21h 31m

£652

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Sun 1/11

19:35-06:40

1 stop30h 05m

London Heathrow

Sun 8/11

12:05-23:21

2 stops16h 16m

£655

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Wed 14/10

10:43-07:15

1 stop15h 32m

London Heathrow

Mon 26/10

07:30-18:52

2 stops15h 22m

£659

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Sun 14/3

06:00-07:10

2 stops21h 10m

London Heathrow

Fri 19/3

06:35-22:57

2 stops20h 22m

£663

Flights are sorted by cheapest return flights first.

Deals found on 3/10

Showing 1-10 of 12 resultsSorted by cheapest first
1
2

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

Cheapflights Insights

Everything you need to know about your flight from Portland to London

No data available for this route at this time. Please check back soon.

Related info for your journey

  • 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 15h 45m. Fly via United Airlines to get the fastest option. The distance between Portland, Maine and London is about 3173 mi.

  • 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.

See more FAQs

Travelling to a place near London?

Book flights to London if you plan to visit one of these locations
Hounslow
Milton Keynes
Luton
Slough
Wembley
Gatwick
Ilford
Hayes
Croydon
Colchester
Eastbourne
Enfield
Brentford
Southend-on-Sea
Barnet
Southall
Watford
Kingston upon Thames
Dagenham
Dover

Browse thousands of different options on Cheapflights for your next trip

Fly with Cheapflights

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

Cheapflights helps you search for flights from Portland to London via 900+ travel sites so you don’t have to. After performing a flight search, users can also filter their flight selection by filtering for price, number of stops, airlines, and so on.

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.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.