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Cheap flights from Portland, Maine to London Heathrow Airport from £249

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 2/9. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
22 May — 29 May1
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 22 April 2026.

Tue 10/1113:35
PWM
-
LHR
1 stop11h 50m
Delta
Tue 17/1106:30
LHR
-
PWM
2 stops20h 53m
Delta
Deal found 20/4£540
Sun 26/414:51
PWM
-
LHR
1 stop14h 29m
Delta
Sun 3/511:45
LHR
-
PWM
2 stops18h 01m
Delta
Deal found 19/4£540
Wed 6/512:46
PWM
-
LHR
2 stops15h 04m
Delta
Mon 11/508:40
LHR
-
PWM
2 stops19h 29m
Delta
Deal found 19/4£543
Tue 10/1113:35
PWM
-
LHR
1 stop14h 25m
KLM
Tue 24/1110:45
LHR
-
PWM
1 stop16h 38m
KLM
Deal found 20/4£545
Fri 8/514:05
PWM
-
LHR
2 stops18h 40m
Virgin Atlantic
Fri 15/506:30
LHR
-
PWM
2 stops21h 39m
Virgin Atlantic
Deal found 20/4£555
Thu 3/914:35
PWM
-
LHR
2 stops18h 15m
Delta
Mon 7/908:40
LHR
-
PWM
2 stops18h 53m
Delta
Deal found 18/4£563
Wed 29/718:57
PWM
-
LHR
1 stop13h 18m
Virgin Atlantic
Fri 28/806:30
LHR
-
PWM
2 stops21h 03m
Virgin Atlantic
Deal found 20/4£576
Tue 18/813:35
PWM
-
LHR
1 stop18h 40m
Virgin Atlantic
Tue 1/906:15
LHR
-
PWM
2 stops21h 18m
Virgin Atlantic
Deal found 22/4£579
Mon 12/1006:00
PWM
-
LHR
1 stop20h 15m
Delta
Sat 24/1009:20
LHR
-
PWM
1 stop18h 03m
Delta
Deal found 19/4£581
Mon 4/505:21
PWM
-
LHR
1 stop20h 04m
Virgin Atlantic
Thu 28/506:30
LHR
-
PWM
2 stops21h 39m
Virgin Atlantic
Deal found 20/4£591
Mon 4/512:46
PWM
-
LHR
1 stop13h 24m
KLM
Thu 28/515:50
LHR
-
PWM
1 stop13h 53m
KLM
Deal found 20/4£596

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 22 April 2026.

Round-trip from

£540

One-way from

£249

Popular in

July

Cheapest in

October

Average price

£634
Delta
  • Delta
  • 8/5-13/5
  • 3 total stops
  • 38h 07m total
  • Portland to London
Search Deals
Delta
  • Delta
  • 2/9
  • 2 total stops
  • 16h 30m total
  • Portland to London
Search Deals
Highest demand for flights based on searches. 23% potential increase in price (£140 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 10% potential price decrease (£44 potential savings vs. average return price).
Search Deals
Average for round-trip flights in April 2026
Search Deals

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 22 April 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 6/5

14:51-06:20

1 stop10h 29m

London Heathrow

Mon 11/5

09:55-23:09

2 stops18h 14m

£540

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 10/5

14:38-08:50

1 stop13h 12m

London Heathrow

Sat 16/5

08:40-00:43

2 stops21h 03m

£540

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 1/9

14:35-07:15

1 stop11h 40m

London Heathrow

Sun 6/9

08:40-22:33

2 stops18h 53m

£540

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 4/5

14:51-08:50

1 stop12h 59m

London Heathrow

Mon 18/5

11:45-00:43

1 stop17h 58m

£545

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 18/8

13:35-13:15

1 stop18h 40m

London Heathrow

Tue 1/9

09:20-22:33

1 stop18h 13m

£545

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 10/5

12:50-07:10

1 stop13h 20m

London Heathrow

Sat 16/5

11:15-23:09

1 stop16h 54m

£545
Fastest return journey

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 4/5

12:46-07:10

1 stop13h 24m

London Heathrow

Thu 28/5

15:50-00:43

1 stop13h 53m

£596
Cheapest one-way

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 4/9

14:35-10:20

1 stop14h 45m

£249
Fastest single journey

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 3/9

14:35-08:50

1 stop13h 15m

£249

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 4/9

16:50-12:05

2 stops14h 15m

£249

Flights are sorted by cheapest return flights first.

Deals found on 18/4

Showing 1-10 of 15 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.

New York (JFK) – chosen by Cheapflights users on 50% 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 £476.

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 £540, Delta can have you in London Heathrow Airport from Portland, Maine in 10h 29m. The distance from Portland, Maine to London Heathrow Airport is about 3173 mi.

  • 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
Milton Keynes
Wembley
Croydon
Hounslow
Northampton
Luton
Gatwick
Ilford
Slough
Hayes
Brentford
Colchester
Watford
Kingston upon Thames
Romford
Eastbourne
Swindon
Ipswich
Southend-on-Sea
Guildford

Browse thousands of different options on Cheapflights for your next trip

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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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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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