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Cheap flights from Portland, Maine to London Heathrow Airport from £255

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 23/7. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
23 Jun — 30 Jun1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Portland to Heathrow

Enter your travel dates to find the best prices.

Cheapest flights from Portland to Heathrow
Explore the most affordable flight options available from Portland to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 24 May 2026.

Wed 11/1119:22
PWM
-
LHR
1 stop10h 28m
United Airlines
Fri 13/1106:50
LHR
-
PWM
2 stops16h 23m
United Airlines
Deal found 19/5£565
Tue 10/1114:35
PWM
-
LHR
2 stops13h 45m
Scandinavian Airlines
Tue 17/1119:30
LHR
-
PWM
2 stops33h 19m
Scandinavian Airlines
Deal found 20/5£618
Tue 10/1106:30
PWM
-
LHR
1 stop18h 50m
Delta
Tue 17/1106:30
LHR
-
PWM
2 stops20h 53m
Delta
Deal found 19/5£645
Mon 2/1112:50
PWM
-
LHR
2 stops15h 30m
Delta
Sat 7/1106:30
LHR
-
PWM
2 stops20h 53m
Delta
Deal found 20/5£648
Tue 1/916:47
PWM
-
LHR
2 stops15h 28m
Delta
Sat 12/908:40
LHR
-
PWM
2 stops20h 19m
Delta
Deal found 23/5£650
Mon 2/1106:00
PWM
-
LHR
2 stops20h 10m
Multiple Airlines
Sat 7/1107:25
LHR
-
PWM
1 stop21h 18m
Multiple Airlines
Deal found 20/5£652
Tue 10/1111:17
PWM
-
LHR
1 stop16h 08m
Austrian Airlines
Tue 17/1108:00
LHR
-
PWM
1 stop15h 13m
Austrian Airlines
Deal found 23/5£658

Find flight deals from Portland to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from Portland (PWM) to Heathrow (LHR). 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 24 May 2026.

Round-trip from

£565

One-way from

£255

Popular in

July

Cheapest in

October

Average price

£544
United Airlines
  • United Airlines
  • 11/11-13/11
  • 3 total stops
  • 26h 51m total
  • Portland to London
Search Deals
Virgin Atlantic
  • Virgin Atlantic
  • 23/7
  • 1 total stop
  • 19h 25m total
  • Portland to London
Search Deals
Highest demand for flights based on searches. 22% potential increase in price (£132 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease (£30 potential savings vs. average return price).
Search Deals
Average for round-trip flights in May 2026
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Cheapflights Fare Finder

 
Customise your flight search to find flights from Portland to Heathrow 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 24 May 2026.
Use the filters below to find and compare flights from Portland to London Heathrow Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 11/11

19:22-10:50

1 stop10h 28m

London Heathrow

Fri 13/11

06:50-18:13

2 stops16h 23m

£565

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 10/11

06:30-06:20

1 stop18h 50m

London Heathrow

Tue 17/11

06:30-22:23

2 stops20h 53m

£645

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 10/11

14:35-08:05

1 stop12h 30m

London Heathrow

Tue 24/11

06:30-23:49

2 stops22h 19m

£645

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 17/11

06:00-06:25

1 stop19h 25m

London Heathrow

Sat 21/11

06:30-22:23

2 stops20h 53m

£645

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 1/9

16:47-13:15

2 stops15h 28m

London Heathrow

Sat 12/9

08:40-23:59

2 stops20h 19m

£650

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 1/9

14:53-10:20

1 stop14h 27m

London Heathrow

Sat 12/9

11:45-23:59

1 stop17h 14m

£667
Fastest return journey

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 10/11

14:35-08:05

1 stop12h 30m

London Heathrow

Tue 24/11

16:10-23:49

1 stop12h 39m

£667
Cheapest one-way
Fastest single journey

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 23/7

12:40-08:50

2 stops15h 10m

£255

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 6/6

14:37-10:20

2 stops38h 43m

£377

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 23/7

09:10-06:30

3 stops16h 20m

£389

Flights are sorted by cheapest return flights first.

Deals found on 22/5

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

Best time to book a flight from Portland to Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow 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 Heathrow Airport

What’s the top stopover airport for flights from Portland, Maine to London Heathrow Airport?

Share of one-stop return flights from Portland, Maine to London Heathrow Airport 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 Heathrow Airport on Cheapflights.

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

Average return fare for one-stop flights from Portland, Maine to London Heathrow Airport, 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 £428.

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

Shortest average travel time for one-stop one-way flights from Portland, Maine to London Heathrow Airport, 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 Heathrow Airport?

Average stopover duration for one-stop one-way flights from Portland, Maine to London Heathrow Airport, 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 Heathrow. 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 Heathrow?

    For a flight from Portland to London Heathrow, you will be flying from Portland. Portland (PWM) is just 2.9 mi from the center of the city. Portland is the only Portland airport and it handles 0 outbound flights to London Heathrow per day. 0 airlines have flights to London Heathrow from Portland on a regular basis.

  • How long is the flight from Portland, Maine to London Heathrow Airport?

    For as low as £565, United Airlines can have you in London Heathrow Airport from Portland, Maine in 10h 28m. The distance from Portland, Maine to London Heathrow Airport is about 3173 mi. This flight may include one or multiple stops.

  • Can I find deals for flights from Portland to Heathrow that include hotel bookings?

    Yes. In addition to deals on Portland to Heathrow flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Portland to Heathrow?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Portland to Heathrow.

  • Can I find deals for business class flights from Portland to Heathrow?

    Yes. Cheapflights offers flight deals from Portland to Heathrow 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 Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Hounslow
Milton Keynes
Croydon
Northampton
Wembley
Luton
Gatwick
Slough
Ilford
Hayes
Brentford
Colchester
Watford
Romford
Kingston upon Thames
Eastbourne
Ipswich
Swindon
Guildford
Southall

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Alternative routes for Portland to Heathrow

See prices for flight routes from nearby airports that may be better suited for you.
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Bangor to Heathrow flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

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

Deals for Portland to Heathrow flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from Portland to Heathrow?

It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from Portland to Heathrow.

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

Yes! Cheapflights helps users easily find flights from Portland to Heathrow with no change fees.

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

Yes, and it’s super simple to set up. Click the bell icon next to the flight deals above and provide a valid email address to enable Price Alerts. That’s it!

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