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Cheap flights from Portland, Maine to London Heathrow Airport from £191

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 7/5. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
10 May — 17 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 10 April 2026.

Sat 24/1014:35
PWM
-
LHR
1 stop10h 45m
Delta
Sat 31/1011:15
LHR
-
PWM
2 stops16h 34m
Delta
Deal found 5/4£540
Sat 2/516:43
PWM
-
LHR
2 stops15h 32m
Delta
Sat 9/508:40
LHR
-
PWM
2 stops19h 29m
Delta
Deal found 7/4£543
Thu 7/516:48
PWM
-
LHR
2 stops14h 22m
Delta
Sun 10/511:45
LHR
-
PWM
2 stops17h 58m
Delta
Deal found 6/4£544
Sat 2/505:21
PWM
-
LHR
1 stop20h 04m
Virgin Atlantic
Sat 9/509:20
LHR
-
PWM
1 stop18h 49m
Virgin Atlantic
Deal found 7/4£545
Thu 7/514:38
PWM
-
LHR
1 stop16h 32m
Delta
Thu 14/509:55
LHR
-
PWM
2 stops19h 48m
Delta
Deal found 7/4£552
Sun 10/506:25
PWM
-
LHR
1 stop18h 55m
Delta
Sat 16/508:55
LHR
-
PWM
2 stops20h 48m
Delta
Deal found 7/4£555
Wed 6/516:43
PWM
-
LHR
2 stops14h 22m
Delta
Mon 11/508:55
LHR
-
PWM
2 stops20h 48m
Delta
Deal found 7/4£555
Thu 7/506:00
PWM
-
LHR
1 stop19h 25m
Virgin Atlantic
Sun 10/513:25
LHR
-
PWM
1 stop14h 44m
Virgin Atlantic
Deal found 8/4£557
Tue 22/916:50
PWM
-
LHR
2 stops15h 25m
Delta
Sun 4/1011:45
LHR
-
PWM
2 stops17h 14m
Delta
Deal found 8/4£558
Sun 10/514:38
PWM
-
LHR
1 stop14h 42m
KLM
Sat 16/511:20
LHR
-
PWM
1 stop18h 23m
KLM
Deal found 7/4£559

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 10 April 2026.

Round-trip from

£540

One-way from

£191

Popular in

July

Cheapest in

October

Average price

£638
Delta
  • Delta
  • 2/5-9/5
  • 3 total stops
  • 31h 32m total
  • Portland to London
Search Deals
KLM
  • KLM
  • 7/5
  • 1 total stop
  • 13h 12m total
  • Portland to London
Search Deals
Highest demand for flights based on searches. 21% potential increase in price (£128 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 10 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

Sun 10/5

14:38-06:45

1 stop11h 07m

London Heathrow

Sat 16/5

06:30-23:09

2 stops21h 39m

£540

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 6/5

16:43-12:05

2 stops14h 22m

London Heathrow

Mon 11/5

09:55-23:09

2 stops18h 14m

£543
Fastest return journey

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 23/8

14:35-07:15

1 stop11h 40m

London Heathrow

Mon 31/8

09:20-22:33

1 stop18h 13m

£545

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 7/5

12:50-08:50

2 stops15h 00m

London Heathrow

Thu 14/5

09:55-00:43

2 stops19h 48m

£555

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 7/5

14:05-13:15

1 stop18h 10m

London Heathrow

Thu 14/5

09:20-23:09

1 stop18h 49m

£557

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 12/9

16:50-12:05

2 stops14h 15m

London Heathrow

Wed 16/9

11:45-23:59

2 stops17h 14m

£558

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 10/5

14:38-10:20

1 stop14h 42m

London Heathrow

Sat 16/5

11:20-00:43

1 stop18h 23m

£559
Cheapest one-way

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 7/5

14:38-08:50

1 stop13h 12m

£191

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 26/9

12:50-13:15

2 stops19h 25m

£250

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 6/7

12:13-06:50

1 stop13h 37m

£273

Flights are sorted by cheapest return flights first.

Deals found on 8/4

Showing 1-10 of 17 resultsSorted by cheapest first
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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 is the cheapest month to book a flight from Portland, Maine to London Heathrow Airport?

Currently, October is the cheapest month in which you can book a flight from Portland, Maine to London Heathrow Airport (average of £324). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of £441). 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.

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 11h 07m. 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.

  • What is the cheapest month to book a flight from Portland, Maine to London Heathrow Airport?

    Currently, October is the cheapest month in which you can book a flight from Portland, Maine to London Heathrow Airport (average of £324). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of £441). 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 Heathrow Airport?

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

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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Boston to Southend flights

Fly with Cheapflights

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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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