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Cheap flights from Portland, Maine to London Heathrow Airport from £239

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 15/5. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
1 Jan — 8 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 2 December 2025.

Sun 14/1206:00PWM - LHR
1 stop9h 35mUnited Airlines
Mon 22/1216:20LHR - PWM
1 stop12h 39mUnited Airlines
Deal found 30/11£572
Mon 15/1210:35PWM - LHR
1 stop19h 30mAustrian Airlines
Mon 22/1218:00LHR - PWM
1 stop29h 11mAustrian Airlines
Deal found 30/11£574
Sat 13/1216:25PWM - LHR
1 stop32h 30mUnited Airlines
Mon 22/1216:20LHR - PWM
1 stop12h 39mUnited Airlines
Deal found 30/11£577
Sun 14/1216:53PWM - LHR
1 stop10h 52mDelta
Sun 21/1212:40LHR - PWM
1 stop15h 10mDelta
Deal found 30/11£597
Sun 14/1216:43PWM - LHR
2 stops13h 42mDelta
Mon 22/1212:40LHR - PWM
1 stop15h 10mDelta
Deal found 30/11£645
Sat 13/1210:15PWM - LHR
2 stops42h 05mAir Canada
Mon 22/1213:25LHR - PWM
2 stops38h 57mAir Canada
Deal found 30/11£652
Sun 14/1206:00PWM - LHR
2 stops24h 15mUnited Airlines
Sun 21/1209:00LHR - PWM
2 stops34h 40mUnited Airlines
Deal found 30/11£767
Sat 13/1219:46PWM - LHR
1 stop10h 19mUnited Airlines
Sun 21/1215:10LHR - PWM
1 stop13h 12mUnited Airlines
Deal found 30/11£800
Mon 15/1206:00PWM - LHR
2 stops20h 10mAir Canada
Mon 22/1209:00LHR - PWM
2 stops19h 22mAir Canada
Deal found 30/11£875
Mon 15/1214:34PWM - LHR
2 stops18h 11mDelta
Mon 22/1220:00LHR - PWM
1 stop21h 23mDelta
Deal found 30/11£881
Wed 17/1207:02PWM - LHR
1 stop19h 18mMultiple Airlines
Sun 21/1212:10LHR - PWM
1 stop16h 32mMultiple Airlines
Deal found 30/11£898

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 2 December 2025.

Round-trip from

£452

Popular in

June

Cheapest in

October

Average price

£1,090
Delta
  • Delta
  • 14/1-21/1
  • 3 total stops
  • 31h 40m total
  • Portland to London
Search Deals
Highest demand for flights based on searches. 13% potential increase in price (£86 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease (£25 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 2 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

Wed 14/1

14:35-06:55

1 stop11h 20m

London Heathrow

Wed 21/1

09:00-00:20

2 stops20h 20m

£452

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 14/1

14:35-08:05

1 stop12h 30m

London Heathrow

Wed 21/1

10:45-22:27

1 stop16h 42m

£457

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 16/1

05:30-06:25

1 stop19h 55m

London Heathrow

Fri 23/1

06:20-22:27

2 stops21h 07m

£471

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 7/2

05:30-09:00

1 stop22h 30m

London Heathrow

Sun 15/2

06:30-23:06

2 stops21h 36m

£474

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 6/2

05:30-09:00

1 stop22h 30m

London Heathrow

Sun 15/2

06:30-23:06

2 stops21h 36m

£474

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 23/1

14:35-07:50

2 stops12h 15m

London Heathrow

Tue 27/1

11:45-00:20

2 stops17h 35m

£475

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 16/1

14:35-10:15

1 stop14h 40m

London Heathrow

Fri 23/1

12:40-00:20

1 stop16h 40m

£476

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 15/5

16:12-06:50

1 stop9h 38m

£239

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 15/5

15:15-21:00

2 stops48h 45m

£336

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 15/5

14:18-18:15

3 stops22h 57m

£593

Flights are sorted by cheapest return flights first.

Deals found on 2/12

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 £293). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of £450). 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 £452, Delta can have you in London Heathrow Airport from Portland, Maine in 11h 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 £293). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of £450). 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
Northampton
Hounslow
Slough
Gatwick
Luton
Ilford
Wembley
Colchester
Brentford
Watford
Hayes
Crawley
Deal
Winchester
Swindon
Romford
Bedford
Chichester

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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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