HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Heathrow

$1,121+ Cheap flights from Islip, NY (ISP) to Heathrow (LHR)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/12. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — LHR
Feb 25 — Mar 41
Wed 2/25
Wed 3/4
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Islip to Heathrow with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheap flight deals from Islip to Heathrow

Cheapest flights from Islip to Heathrow
Explore the most affordable flight options available from Islip to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 26, 2026.

This Kiwi.com deal was found by Cheapflights users on 1/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/129:59 am
ISP
-
LHR
1 stop17h 51m
Multiple Airlines
Thu 3/198:45 am
LHR
-
ISP
2 stops32h 02m
Multiple Airlines
Deal found 1/26$1,121
This Mytrip deal was found by Cheapflights users on 1/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/119:59 am
ISP
-
LHR
2 stops17h 11m
Multiple Airlines
Wed 3/188:35 pm
LHR
-
ISP
2 stops26h 09m
Multiple Airlines
Deal found 1/25$1,226
This Icelandair deal was found by Cheapflights users on 1/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/204:05 pm
ISP
-
LHR
2 stops14h 50m
Multiple Airlines
Fri 9/111:05 pm
LHR
-
ISP
2 stops14h 00m
Multiple Airlines
Deal found 1/25$1,230
This Ovago deal was found by Cheapflights users on 1/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/59:59 am
ISP
-
LHR
1 stop17h 01m
Multiple Airlines
Sun 7/128:10 pm
LHR
-
ISP
1 stop19h 55m
Multiple Airlines
Deal found 1/25$1,722

Find flight deals from Islip to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from Islip (ISP) 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 January 26, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$1,121
(Kiwi.com)

Popular in

December

Cheapest in

September

Average price

$561
Provider with most accurate pricing for Islip Long Island-London Heathrow flight deals.
Search Deals
Provider most trusted by Cheapflights users for Islip Long Island-London Heathrow flights.
Search Deals
From Islip Long Island to London Heathrow
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($28 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($12 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Islip 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 2,558,603 searches. Data last updated January 26, 2026.
Use the filters below to find and compare flights from Islip to London Heathrow Airport that are best for you.

Fly from

Islip

Fly to

Heathrow

Route

Depart

Return

Price

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Wed 3/11

9:59 am-7:10 am

2 stops17h 11m

London Heathrow

Wed 3/18

8:35 pm-6:44 pm

2 stops26h 09m

$1,226

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Thu 3/12

9:59 am-7:50 am

1 stop17h 51m

London Heathrow

Thu 3/19

9:40 am-6:44 pm

1 stop13h 04m

$1,262

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sun 7/5

9:59 am-8:00 am

1 stop17h 01m

London Heathrow

Sun 7/12

8:10 pm-11:05 am

1 stop19h 55m

$1,722

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/25

  • Most accurate provider: When it comes to deals on Islip, New York-London Heathrow Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Islip, New York-London Heathrow Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Islip, New York-London Heathrow Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Islip, New York-London Heathrow Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Islip, New York-London Heathrow Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Islip to Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow from Islip with our price prediction graph.
Estimated round-trip 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 Islip to London Heathrow Airport

What is the cheapest month to book a flight from Islip, New York to London Heathrow Airport?

Currently, November is the cheapest month in which you can book a flight from Islip, New York to London Heathrow Airport (average of $392). Flying from Islip, New York to London Heathrow Airport in June is currently the most expensive (average of $578). 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 Islip 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 Islip to London Heathrow?

    Islip Long Island (ISP), located 7.2 mi from the city center, is the airport you fly out of when you book flights from Islip to London Heathrow. 0 airlines have flights from Long Island to London Heathrow on a regular basis. Booking flights from Islip Long Island to London Heathrow should not be difficult; the airport handles an average of 0 outbound flights to London Heathrow per day.

  • Can I find deals for flights from Islip to Heathrow that include hotel bookings?

    Yes. In addition to deals on Islip to Heathrow flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Islip to Heathrow?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Islip to Heathrow.

  • Can I find deals for business class flights from Islip to Heathrow?

    Yes. Cheapflights offers flight deals from Islip 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 Islip, New York to London Heathrow Airport?

    Currently, November is the cheapest month in which you can book a flight from Islip, New York to London Heathrow Airport (average of $392). Flying from Islip, New York to London Heathrow Airport in June is currently the most expensive (average of $578). 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

Traveling to a place near London Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Ilford
Hounslow
Southend-on-Sea
Harrow
Croydon
Eastleigh
Gatwick
Dartford
Dover
Winchester
Orpington
Watford
Northampton
Hayes
Borehamwood
Broadway
Aylesbury
Chipping Norton
Horley
Kingston upon Thames

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Islip to Heathrow

See prices for flight routes from nearby airports that may be better suited for you.
John F Kennedy Intl to Heathrow flights
Newark to Heathrow flights
LaGuardia to Heathrow flights
John F Kennedy Intl to London City flights
Newark to Gatwick flights
John F Kennedy Intl to Gatwick flights
John F Kennedy Intl to Stansted flights
LaGuardia to Gatwick flights
John F Kennedy Intl to Luton flights
Newark to London City flights
Newark to Stansted flights
Newark to Luton flights
LaGuardia to Stansted flights
LaGuardia to Luton flights
Syracuse to Heathrow flights
Rochester to Heathrow flights
Buffalo to Heathrow flights
White Plains to Heathrow flights
LaGuardia to London City flights
Buffalo to Gatwick flights
Albany to Heathrow flights
Syracuse to Gatwick flights
Syracuse to London City flights
Rochester to Gatwick flights
Albany to London City flights
John F Kennedy Intl to Southend flights
Buffalo to London City flights
Rochester to London City flights
Syracuse to Stansted flights
Ithaca to Heathrow flights
Rochester to Stansted flights
Buffalo to Stansted flights
Albany to Gatwick flights
Watertown to Heathrow flights
Newark to Southend flights
Rutland to Heathrow flights
Elmira to London City flights
Elmira to Heathrow flights
White Plains to Gatwick flights
Binghamton to Heathrow flights
Stewart to London City flights
Stewart to Gatwick flights
Stewart to Heathrow flights
Stewart to Luton flights

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.