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Cheap flights from Portland, Maine to London Heathrow Airport from £204

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 3/5. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
29 Apr — 6 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 30 March 2026.

Tue 10/1113:35
PWM
-
LHR
1 stop13h 15m
Virgin Atlantic
Wed 18/1112:30
LHR
-
PWM
1 stop14h 53m
Virgin Atlantic
Deal found 27/3£529
Tue 10/1114:35
PWM
-
LHR
1 stop12h 30m
KLM
Wed 18/1106:30
LHR
-
PWM
2 stops14h 40m
KLM
Deal found 27/3£531
Sun 19/405:21
PWM
-
LHR
1 stop20h 04m
Multiple Airlines
Mon 4/520:05
LHR
-
PWM
1 stop23h 06m
Multiple Airlines
Deal found 29/3£544
Sun 19/405:21
PWM
-
LHR
1 stop20h 04m
KLM
Mon 4/511:45
LHR
-
PWM
1 stop18h 01m
KLM
Deal found 28/3£545
Wed 6/514:51
PWM
-
LHR
1 stop16h 14m
Delta
Mon 11/508:40
LHR
-
PWM
2 stops19h 29m
Delta
Deal found 28/3£547
Sun 19/414:51
PWM
-
LHR
1 stop10h 29m
Delta
Mon 4/509:55
LHR
-
PWM
2 stops18h 28m
Delta
Deal found 28/3£548
Fri 24/405:21
PWM
-
LHR
1 stop20h 04m
Virgin Atlantic
Fri 1/509:20
LHR
-
PWM
1 stop19h 03m
Virgin Atlantic
Deal found 27/3£550
Wed 6/514:51
PWM
-
LHR
1 stop12h 59m
KLM
Mon 11/508:20
LHR
-
PWM
1 stop21h 23m
KLM
Deal found 28/3£553

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 30 March 2026.

Round-trip from

£544

One-way from

£204

Popular in

December

Cheapest in

October

Average price

£804
Air France
  • Air France
  • 19/4-4/5
  • 2 total stops
  • 43h 10m total
  • Portland to London
Search Deals
KLM
  • KLM
  • 3/5
  • 1 total stop
  • 13h 24m total
  • Portland to London
Search Deals
Highest demand for flights based on searches. 8% potential increase in price (£46 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease (£31 potential savings vs. average return price).
Search Deals
Average for round-trip flights in March 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 30 March 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 19/4

05:21-06:25

1 stop20h 04m

London Heathrow

Mon 4/5

20:05-14:11

1 stop23h 06m

£544

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 10/5

06:25-06:20

1 stop18h 55m

London Heathrow

Sat 16/5

08:40-00:43

2 stops21h 03m

£545

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 19/4

14:51-06:20

1 stop10h 29m

London Heathrow

Mon 4/5

09:55-23:23

2 stops18h 28m

£547

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 6/5

16:43-13:05

2 stops15h 22m

London Heathrow

Mon 11/5

08:40-23:09

2 stops19h 29m

£551

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 6/5

14:51-08:50

1 stop12h 59m

London Heathrow

Mon 11/5

08:20-00:43

1 stop21h 23m

£553
Fastest return journey

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 13/5

14:38-08:50

1 stop13h 12m

London Heathrow

Wed 20/5

16:05-00:43

1 stop13h 38m

£553

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 30/8

14:35-06:20

1 stop10h 45m

London Heathrow

Tue 8/9

12:50-23:59

1 stop16h 09m

£575

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 29/8

16:50-12:05

2 stops14h 15m

London Heathrow

Mon 7/9

08:40-22:33

2 stops18h 53m

£576
Cheapest one-way

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 3/5

12:46-07:10

1 stop13h 24m

£204

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 3/5

12:46-10:30

2 stops16h 44m

£219

Flights are sorted by cheapest return flights first.

Deals found on 28/3

Showing 1-10 of 18 resultsSorted by cheapest first
1
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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 £328). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of £446). 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.

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

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 £545, Delta can have you in London Heathrow Airport from Portland, Maine in 18h 55m. 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.

  • 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 £328). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of £446). 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
Slough
Ilford
Luton
Hayes
Brentford
Colchester
Guildford
Watford
Kingston upon Thames
Romford
Eastbourne
Swindon
Bedford
Chelmsford

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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
Bangor to Heathrow 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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