$1,083 Cheap Flights from London (LHR) to Islip (ISP)

View $1,083 flight on Sat, Jan 3, 2026Opens in a new window

Popular airlines from Heathrow Airport (LHR) to MacArthur Airport (ISP)

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Cheap Flights from London to Islip (LHR-ISP)

Prices were available within the past 7 days and start at $1,083 for one-way flights and $2,264 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Aer Lingus
Mon, Aug 11 - Sat, Aug 16
LHR
London
ISP
Islip
$2,264 Roundtrip, found 2 days ago
$2,264
Roundtrip
found 2 days ago
Select Aer Lingus flight, departing Mon, Aug 11 from London to Islip, returning Sat, Aug 16, priced at $2,264 found 2 days ago
Aer Lingus
Mon, Aug 11 - Sat, Aug 16
LHR
London
ISP
Islip
$2,340 Roundtrip, found 2 days ago
$2,340
Roundtrip
found 2 days ago
Select Aer Lingus flight, departing Mon, Aug 11 from London to Islip, returning Sat, Aug 16, priced at $2,340 found 2 days ago
Aer Lingus
Mon, Aug 11 - Sat, Aug 16
LHR
London
ISP
Islip
$2,421 Roundtrip, found 2 days ago
$2,421
Roundtrip
found 2 days ago
Select Aer Lingus flight, departing Mon, Aug 11 from London to Islip, returning Sat, Aug 16, priced at $2,421 found 2 days ago
Aer Lingus
Mon, Aug 11 - Sat, Aug 16
LHR
London
ISP
Islip
$2,496 Roundtrip, found 2 days ago
$2,496
Roundtrip
found 2 days ago
Select Aer Lingus flight, departing Mon, Aug 11 from London to Islip, returning Sat, Aug 16, priced at $2,496 found 2 days ago
Flights from London (LHR) to Islip (ISP)
Origin airport
Heathrow
Destination airport
MacArthur
Roundtrip price
$2,264
Distance
3408 mi

London to Islip Flights

The cheapest times to fly from London to Islip

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from London to Islip are during the month of August. You can find some of the cheapest flights from London to Islip with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from London to Islip

Sunday is one of the best days to book for cheap flights from London to Islip: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from London to Islip

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from London to Islip in 2025. You can also book with separate airlines for your outbound and return journeys, from $1,083 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap London to Islip flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your London to Islip airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from Heathrow Airport (LHR) to MacArthur Airport (ISP) cost?
Discover the latest flight deals from LHR to ISP by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from LHR to ISP?
The cheapest flights from LHR to ISP are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from LHR to ISP?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that'll take you from LHR to ISP. Sort your results by "Price (lowest to highest)" to snap up a great deal.
How many flights per day from Heathrow Airport (LHR) to MacArthur Airport (ISP)?
You'll need to book a flight with a layover if you're traveling from Heathrow Airport (LHR) to MacArthur Airport (ISP). Direct flights don't operate daily on this route. However, just filter your search to include one or more stops to find an option that works for you.
What day of the week has the most flights from LHR to ISP?
Friday is typically the busiest day for flights, while Tuesday tends to be the quietest.* Just remember that flight schedules can vary depending on a range of factors, such as the time of year and airline.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Heathrow Airport (LHR) to MacArthur Airport (ISP)?
To reach MacArthur Airport (ISP) on schedule, choose a flight that takes off from Heathrow Airport (LHR) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this hour.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports do you fly into for Islip from Heathrow Airport (LHR)?
Check out your flight options from Heathrow Airport (LHR) to John F. Kennedy Intl. Airport (JFK). This is the only Islip airport you can jet into if you're taking a direct flight.
Is it cheaper to buy a plane ticket from Heathrow Airport (LHR) to MacArthur Airport (ISP) last-minute?
Booking your flight from LHR to ISP right before your journey is typically more expensive. But if you're flexible with your departure dates and times, you could score a cheap last-minute fare.
Is it cheaper to book a LHR to ISP flight and hotel package?
You can save money by securing a LHR to ISP flight and hotel package compared to booking separately. In fact, travelers could save hundreds of dollars by bundling with Expedia. And it's simple to manage everything in one place. Once you've chosen your ideal flights and accommodations, you can add extras such as tours, car rentals and activities.
Can I cancel or change the date of my flight from Heathrow Airport (LHR) to MacArthur Airport (ISP)?
In most instances, you're able to reschedule or cancel your LHR to ISP flight. However, additional charges may apply, especially if you booked over 24 hours ago. Double-check your itinerary for the airline's rules and fees on flight changes, or if you'd like further information, head to our Customer Service portal.

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*Available to One Key members.