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Cheap flights from Portland, Maine to London Heathrow Airport from £279

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 6/12. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
1 Dec — 8 Dec1
1 adult
1 adult, Economy, 0 bags

Cheap 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 1 November 2025.

Round-trip from

£514

One-way from

£279

Popular in

June

Cheapest in

May

Average price

£624
Air Canada
  • Air Canada
  • 30/11-7/12
  • 4 total stops
  • 56h 37m total
  • Portland to London
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6/12
  • 6/12
  • 3 total stops
  • 42h 34m total
  • Portland to London
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Highest demand for flights based on searches. 10% potential increase in price (£68 potential increase over avg. return price).
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Cheapest flight prices on average. 4% potential price decrease (£26 potential savings vs. average return price).
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Average for round-trip flights in November 2025
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Find 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 1 November 2025.

Sun 30/1106:00PWM - LHR
2 stops22h 20mAir Canada
Sun 7/1213:25LHR - PWM
2 stops34h 17mAir Canada
Deal found 31/10£514
Sun 30/1105:30PWM - LHR
1 stop20h 10mUnited Airlines
Sun 7/1206:50LHR - PWM
2 stops16h 52mUnited Airlines
Deal found 31/10£547
Mon 15/1216:53PWM - LHR
1 stop10h 52mAir France
Mon 22/1208:55LHR - PWM
1 stop18h 48mAir France
Deal found 30/10£571
Mon 15/1214:34PWM - LHR
2 stops18h 11mDelta
Mon 22/1208:55LHR - PWM
1 stop18h 48mDelta
Deal found 30/10£574
Sun 14/1215:20PWM - LHR
1 stop10h 00mUnited Airlines
Sun 21/1216:00LHR - PWM
1 stop12h 22mUnited Airlines
Deal found 31/10£626
Sun 14/1206:08PWM - LHR
1 stop21h 52mVirgin Atlantic
Sun 21/1210:45LHR - PWM
1 stop16h 58mVirgin Atlantic
Deal found 30/10£647
Sun 14/1206:08PWM - LHR
2 stops19h 57mDelta
Sun 21/1220:00LHR - PWM
1 stop21h 20mDelta
Deal found 30/10£650
Sun 9/1106:35PWM - LHR
2 stops34h 05mScandinavian Airlines
Wed 12/1106:40LHR - PWM
2 stops22h 14mScandinavian Airlines
Deal found 30/10£683
Sun 14/1210:35PWM - LHR
2 stops39h 35mAir Canada
Sun 21/1213:25LHR - PWM
2 stops38h 57mAir Canada
Deal found 30/10£744
Mon 15/1215:00PWM - LHR
2 stops14h 50mUnited Airlines
Mon 22/1207:55LHR - PWM
2 stops20h 27mUnited Airlines
Deal found 30/10£764

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 1 November 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

Tue 11/11

12:48-08:45

1 stop14h 57m

London Heathrow

Tue 18/11

11:45-23:54

2 stops17h 09m

£451

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 12/11

11:25-06:55

1 stop14h 30m

London Heathrow

Tue 18/11

10:00-23:19

2 stops18h 19m

£451

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 10/11

11:25-06:55

1 stop14h 30m

London Heathrow

Tue 18/11

10:00-23:54

2 stops18h 54m

£451

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/11

13:25-07:50

1 stop13h 25m

London Heathrow

Tue 18/11

14:30-23:54

1 stop14h 24m

£456

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/11

13:25-06:25

1 stop12h 00m

London Heathrow

Sun 16/11

12:30-22:19

1 stop14h 49m

£494

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 12/11

14:30-06:20

1 stop10h 50m

London Heathrow

Mon 17/11

16:35-23:54

1 stop12h 19m

£494

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 12/11

13:25-06:25

1 stop12h 00m

London Heathrow

Sun 16/11

12:30-22:19

1 stop14h 49m

£494

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 6/12

11:16-10:50

3 stops42h 34m

£279

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 6/12

06:00-20:35

2 stops33h 35m

£297

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 6/12

16:25-07:55

1 stop34h 30m

£314

Flights are sorted by cheapest return flights first.

Deals found on 31/10

Showing 1-10 of 11 results
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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, February is the cheapest month in which you can book a flight from Portland, Maine to London Heathrow Airport (average of £272). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of £453). 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 £451, Delta can have you in London Heathrow Airport from Portland, Maine in 14h 57m. 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, February is the cheapest month in which you can book a flight from Portland, Maine to London Heathrow Airport (average of £272). Flying from Portland, Maine to London Heathrow Airport in June is currently the most expensive (average of £453). 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
Gatwick
Hounslow
Northampton
Luton
Ilford
Wembley
Deal
Hayes
Colchester
Watford
Winchester
Chichester
Swindon
Crawley
Romford
Brentford
Ipswich

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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

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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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