Cheap flights from Portland to London Heathrow

Compare Portland to London Heathrow flight deals

Find the cheapest month or even day of the year to fly to London Heathrow

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Flight deals from Portland to London Heathrow

Looking for a cheap last-minute deal or the best return flight from Portland to London Heathrow? Find the lowest prices on one-way and return tickets right here.

Find the cheapest month to fly from Portland to London Heathrow

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like Portland to London Heathrow flights are currently cheapest in October.

Portland to London: Flight information

The things to know before you go.
Cheapest flight found$277
Cheapest month to flyOctober

Finding cheap flights from Portland to London Heathrow: Frequently asked questions

The best price we found for a return flight from Portland to London Heathrow is $815. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.
Currently, there are no airlines that fly direct from Portland to London Heathrow. But we found flights with one or more stops from $815.
As of February 2026, there are no flights flying from Portland to London Heathrow.
The cheapest month to fly from Portland to London Heathrow is usually April.
After crunching the numbers on our flight calendar, we found that it's currently cheapest to fly from Portland Airport to London Heathrow Airport on Wednesday, 1 April 2026.
No airlines currently offer direct flights between Portland Airport and London Heathrow Airport. Most routes have one or more stops.
We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to London Heathrow but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.
We crunched all the numbers in our flight calendar and it looks like the cheapest time to book a flight to London is around 40 days in advance, so don’t leave your flight to the last minute.
Currently, Delta offers the cheapest flight tickets to London Heathrow.

Travelling from Portland International Jetport Airport (PWM) to London Heathrow Airport (LHR): what you need to know

  • London is four hours ahead of Portland and observes the UTC+0 timezone.

  • To ensure you catch your PWM to LHR flight, leave plenty of time for things like check-in and baggage drop. Arriving two hours ahead of international departures and an hour before domestic flights is the general travel rule.

  • During popular months such as August, you'll want to get to the airport earlier than normal. Plan to arrive two hours before domestic departures and four hours ahead for international flights when you fly during a peak period in general.

  • If you want to add a stop to your trip, just deselect 'Direct flights only' when searching for your ticket from Portland International Jetport Airport to London Heathrow Airport. These are the most popular stopovers between PWM and LHR:

    • John F. Kennedy International Airport

    • Washington Dulles International Airport

    • Newark Liberty International Airport

How to find the cheapest flights from Portland International Jetport Airport (PWM) to London Heathrow Airport (LHR)

  • $277 is the lowest price for a one-way Portland International Jetport Airport to London Heathrow Airport flight. Return flights start from $815. These prices may change depending on demand and availability.

  • It's usually smart to book as early as possible if you want to find cheap tickets from PWM to LHR. That's because flight prices are based on demand, which tends to increase closer to departure.

  • The 'Whole month' search function shows you the cheapest flights from Portland International Jetport Airport to London Heathrow Airport across every month. It's a great way to find a bargain if your dates are flexible.

  • You don't need to check every day to find out if fares have dropped when you set up a Price Alert. We'll notify you as soon as there's a change in price on cheap flights from PWM to LHR.

  • Tailor your trip with filters. Pick your ideal arrival and departure times, airlines and total journey duration. You can also sort the results by 'Cheapest,' 'Fastest' or 'Best' flights from Portland International Jetport Airport to London Heathrow Airport.

Handy information about Portland International Jetport Airport (PWM)

  • PWM is located at 1001 Westbrook Street.

  • Portland International Jetport Airport maintains a solid on-time record, so you're unlikely to face delays. Departures from PWM arrive at their destination as scheduled 82.15% of the time.

  • Portland International Jetport Airport is about 8 kilometres from central Portland. If you're catching a cab, ride-sharing or driving from the centre, it'll take you 15 minutes or so to get there, depending on the traffic.

  • The trip when using public transport takes about 40 minutes.

  • Get your journey off to a stress-free start by staying near PWM. Whether you have an early flight from Portland International Jetport Airport to London Heathrow Airport or just don't want to be rushed, these hotels are the answer:

Arriving at London Heathrow Airport (LHR)

Getting from London Heathrow Airport (LHR) to central London

  • London Heathrow Airport is roughly 31 kilometres from central London. The drive time takes around 55 minutes.

  • Getting to the centre by public transport takes around 1 hour.

When to fly to London Heathrow Airport (LHR)

  • It's time to choose your travel dates for your flight from Portland International Jetport Airport to London Heathrow Airport. July is the busiest month to visit London. If you prefer a quieter vibe, go in February.

  • The warmest month in London is July, with the temperature ranging between 11ºC (52ºF) and 26ºC (79ºF). Lock in your flights from Portland International Jetport Airport to London Heathrow Airport in this month if you like this kind of weather.

  • If you'd rather travel in cooler conditions, look for a cheap ticket from PWM to LHR in January. Temperatures average between 0ºC (32ºF) and 9ºC (48ºF) then.

Explore more of United Kingdom

  • London is easy to fall in love with, but there are so many other parts of United Kingdom just waiting to be explored. Around 161 kilometres north-west of London, a visit to Birmingham will keep you on the go. Check out popular attractions like Cadbury World, The Library of Birmingham and National Sea Life Centre.

  • Bristol is another sought-after destination in United Kingdom and is around 177 kilometres west of London. No trip is complete without a visit to Clifton Suspension Bridge, Cabot Tower and Brandon Hill Nature Park.

Prices shown on this page are estimated lowest prices only. Found in the last 45 days.