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Cheap flights from Portland, Maine to London Heathrow Airport from £341

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 17/4. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
12 Jan — 19 Jan1
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 13 December 2025.

Fri 12/1206:00PWM - LHR
1 stop9h 35mUnited Airlines
Fri 19/1207:25LHR - PWM
1 stop19h 04mUnited Airlines
Deal found 11/12£646
Fri 26/1207:17PWM - LHR
1 stop20h 58mMultiple Airlines
Mon 29/1211:45LHR - PWM
1 stop16h 06mMultiple Airlines
Deal found 12/12£744
Fri 12/1206:00PWM - LHR
1 stop20h 50mMultiple Airlines
Fri 19/1216:25LHR - PWM
1 stop24h 24mMultiple Airlines
Deal found 11/12£923
Fri 26/1207:17PWM - LHR
1 stop19h 03mAmerican Airlines
Mon 29/1213:10LHR - PWM
2 stops15h 35mAmerican Airlines
Deal found 12/12£963
Fri 26/1206:00PWM - LHR
2 stops19h 30mUnited Airlines
Mon 29/1209:30LHR - PWM
2 stops19h 29mUnited Airlines
Deal found 12/12£984
Fri 26/1206:00PWM - LHR
3 stops20h 10mAir Canada
Mon 29/1209:00LHR - PWM
3 stops19h 22mAir Canada
Deal found 12/12£1,070

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 13 December 2025.

Round-trip from

£437

One-way from

£341

Popular in

December

Cheapest in

October

Average price

£1,100
Delta
  • Delta
  • 13/3-15/3
  • 3 total stops
  • 41h 45m total
  • Portland to London
Search Deals
KLM
  • KLM
  • 17/4
  • 1 total stop
  • 14h 40m total
  • Portland to London
Search Deals
Highest demand for flights based on searches. 4% potential increase in price (£26 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease (£26 potential savings vs. average return price).
Search Deals
Average for round-trip flights in December 2025
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 13 December 2025.
Use the filters below to find and compare flights from Portland to London Heathrow Airport that are best for you.

Fly from

Portland

Fly to

Heathrow

Route

Depart

Return

Price

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 13/3

06:25-06:20

1 stop19h 55m

London Heathrow

Sun 15/3

06:20-00:10

2 stops21h 50m

£437

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 14/2

06:00-21:20

1 stop10h 20m

London Heathrow

Wed 18/2

09:00-23:20

2 stops19h 20m

£470

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 25/1

14:35-10:15

1 stop14h 40m

London Heathrow

Sun 1/2

11:45-00:20

2 stops17h 35m

£470

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 13/2

06:00-21:20

1 stop10h 20m

London Heathrow

Wed 18/2

09:00-23:20

2 stops19h 20m

£470

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 13/3

06:25-06:20

1 stop19h 55m

London Heathrow

Mon 16/3

10:00-00:10

2 stops18h 10m

£470

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 21/1

14:31-06:40

1 stop11h 09m

London Heathrow

Sun 25/1

13:25-14:31

2 stops30h 06m

£475

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 10/1

14:31-10:50

1 stop15h 19m

London Heathrow

Sat 17/1

13:25-14:31

2 stops30h 06m

£476

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 13/2

06:00-20:35

2 stops33h 35m

London Heathrow

Thu 19/2

09:00-23:20

2 stops19h 20m

£481

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 10/1

06:00-07:10

2 stops20h 10m

London Heathrow

Sat 17/1

11:10-13:56

2 stops31h 46m

£481

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 31/3

06:00-20:45

1 stop9h 45m

London Heathrow

Tue 14/4

11:55-23:36

1 stop16h 41m

£489

Flights are sorted by cheapest return flights first.

Deals found on 12/12

Showing 1-10 of 15 results
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 is the cheapest month to book a flight from Portland, Maine to London Heathrow Airport?

Currently, January is the cheapest month in which you can book a flight from Portland, Maine to London Heathrow Airport (average of £290). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of £444). 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 £470, Delta can have you in London Heathrow Airport from Portland, Maine in 10h 20m. 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, January is the cheapest month in which you can book a flight from Portland, Maine to London Heathrow Airport (average of £290). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of £444). 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
Croydon
Slough
Hounslow
Northampton
Luton
Gatwick
Wembley
Ilford
Brentford
Colchester
Hayes
Watford
Crawley
Swindon
Winchester
Bedford
Romford
Chichester
Eastbourne

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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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