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Cheap flights from Portland, Maine to London Heathrow Airport from £282

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 3/4. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
11 Apr — 18 Apr1
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 12 March 2026.

Tue 11/809:15
PWM
-
LHR
2 stops18h 25m
United Airlines
Wed 12/814:10
LHR
-
PWM
2 stops14h 49m
United Airlines
Deal found 10/3£526
Wed 9/905:15
PWM
-
LHR
2 stops22h 20m
United Airlines
Tue 15/906:50
LHR
-
PWM
2 stops22h 09m
United Airlines
Deal found 7/3£534
Wed 7/1011:30
PWM
-
LHR
1 stop20h 35m
Delta
Tue 13/1006:30
LHR
-
PWM
2 stops22h 19m
Delta
Deal found 7/3£535
Thu 17/914:35
PWM
-
LHR
2 stops22h 05m
Scandinavian Airlines
Mon 28/906:40
LHR
-
PWM
2 stops22h 19m
Scandinavian Airlines
Deal found 9/3£540
Mon 9/1111:17
PWM
-
LHR
2 stops28h 18m
Air Canada
Fri 13/1113:25
LHR
-
PWM
2 stops31h 44m
Air Canada
Deal found 8/3£541
Wed 6/506:00
PWM
-
LHR
1 stop9h 45m
JetBlue
Mon 11/511:55
LHR
-
PWM
1 stop16h 41m
JetBlue
Deal found 8/3£550
Wed 13/506:00
PWM
-
LHR
1 stop9h 45m
JetBlue
Tue 19/511:55
LHR
-
PWM
1 stop16h 41m
JetBlue
Deal found 10/3£550
Fri 8/506:00
PWM
-
LHR
1 stop22h 30m
JetBlue
Wed 13/511:55
LHR
-
PWM
1 stop16h 41m
JetBlue
Deal found 9/3£553
Mon 9/1106:00
PWM
-
LHR
1 stop10h 20m
United Airlines
Fri 13/1116:00
LHR
-
PWM
1 stop11h 57m
United Airlines
Deal found 8/3£556
Fri 1/506:00
PWM
-
LHR
1 stop9h 45m
JetBlue
Wed 13/511:55
LHR
-
PWM
1 stop16h 41m
JetBlue
Deal found 8/3£561
Sat 4/406:00
PWM
-
LHR
1 stop9h 45m
JetBlue
Mon 13/411:55
LHR
-
PWM
1 stop17h 04m
JetBlue
Deal found 8/3£563

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 12 March 2026.

Round-trip from

£526

One-way from

£282

Popular in

December

Cheapest in

October

Average price

£794
United Airlines
  • United Airlines
  • 11/8-12/8
  • 4 total stops
  • 33h 14m total
  • Portland to London
Search Deals
JetBlue
  • JetBlue
  • 3/4
  • 1 total stop
  • 9h 45m 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 12 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

Tue 21/4

19:33-10:40

1 stop10h 07m

London Heathrow

Tue 28/4

06:50-10:22

2 stops32h 32m

£583

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/8

19:35-14:40

2 stops14h 05m

London Heathrow

Wed 12/8

16:40-23:59

1 stop12h 19m

£588

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 1/9

14:35-06:55

1 stop11h 20m

London Heathrow

Thu 3/9

12:15-23:59

1 stop16h 44m

£593

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/8

12:00-06:45

1 stop13h 45m

London Heathrow

Tue 18/8

07:25-19:19

2 stops16h 54m

£600

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 21/4

18:01-11:15

1 stop12h 14m

London Heathrow

Tue 28/4

11:10-00:13

1 stop18h 03m

£600

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 12/8

09:15-06:45

1 stop16h 30m

London Heathrow

Mon 17/8

06:50-23:59

2 stops22h 09m

£606

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 5/5

16:43-13:15

2 stops15h 32m

London Heathrow

Fri 29/5

06:30-00:43

2 stops23h 13m

£609

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 12/5

14:08-10:40

1 stop15h 32m

London Heathrow

Wed 20/5

06:55-21:19

2 stops19h 24m

£617

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 7/4

15:22-08:20

1 stop11h 58m

London Heathrow

Tue 14/4

06:50-18:58

2 stops17h 08m

£617

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 6/5

16:43-12:05

2 stops14h 22m

London Heathrow

Mon 11/5

11:45-00:43

2 stops17h 58m

£620

Flights are sorted by cheapest return flights first.

Deals found on 8/3

Showing 1-10 of 13 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.

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 £583, United Airlines can have you in London Heathrow Airport from Portland, Maine in 10h 07m. 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 £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
Luton
Hounslow
Slough
Gatwick
Ilford
Hayes
Brentford
Colchester
Guildford
Watford
Kingston upon Thames
Chelmsford
Eastbourne
Ipswich
Swindon
Bedford

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 London City flights
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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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