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$248+ Cheap flights from Islip, NY to Philadelphia (ISP - PHL)

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 2/7. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — PHL
Feb 25 — Mar 41
Wed 2/25
Wed 3/4
1 adult, Economy
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Cheap flight deals from Islip to Philadelphia

Cheapest flights from Islip to Philadelphia
Explore the most affordable flight options available from Islip to Philadelphia. 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 1/24. 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.
Sat 2/711:50 am
ISP
-
PHL
1 stop6h 03m
Multiple Airlines
Mon 2/95:17 pm
PHL
-
ISP
1 stop18h 42m
Multiple Airlines
Deal found 1/24$248
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.
Fri 1/302:01 pm
ISP
-
PHL
2 stops24h 43m
Multiple Airlines
Mon 2/25:17 pm
PHL
-
ISP
1 stop18h 42m
Multiple Airlines
Deal found 1/26$280
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 1/309:43 pm
ISP
-
PHL
1 stop12h 54m
Frontier
Sun 2/110:45 pm
PHL
-
ISP
1 stop20h 03m
Frontier
Deal found 1/25$298
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/97:20 pm
ISP
-
PHL
1 stop27h 40m
Multiple Airlines
Fri 2/1310:59 pm
PHL
-
ISP
1 stop11h 47m
Multiple Airlines
Deal found 1/25$302
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.
Sat 1/3111:50 am
ISP
-
PHL
1 stop6h 03m
Multiple Airlines
Mon 2/25:17 pm
PHL
-
ISP
1 stop18h 42m
Multiple Airlines
Deal found 1/26$310
This Kiwi.com deal was found by Cheapflights users on 1/24. 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 2/57:26 pm
ISP
-
PHL
2 stops22h 45m
Multiple Airlines
Mon 2/95:17 pm
PHL
-
ISP
1 stop18h 42m
Multiple Airlines
Deal found 1/24$313
This Kiwi.com deal was found by Cheapflights users on 1/24. 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.
Fri 2/69:43 pm
ISP
-
PHL
1 stop12h 54m
Multiple Airlines
Mon 2/95:17 pm
PHL
-
ISP
1 stop18h 42m
Multiple Airlines
Deal found 1/24$331
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 1/309:43 pm
ISP
-
PHL
2 stops13h 35m
Multiple Airlines
Sun 2/18:43 pm
PHL
-
ISP
1 stop22h 05m
Multiple Airlines
Deal found 1/25$364

Find flight deals from Islip to Philadelphia

Discover tips and strategies to find the most affordable flight options for your journey from Islip (ISP) to Philadelphia (PHL). 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

$248
(Kiwi.com)

Popular in

October

Cheapest in

March

Average price

$377
Provider with most accurate pricing for Islip Long Island-Philadelphia flight deals.
Search Deals
Provider most trusted by Cheapflights users for Islip Long Island-Philadelphia flights.
Search Deals
From Islip Long Island to Philadelphia
Search Deals
Highest demand for flights based on searches. 14% potential increase in price ($73 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($25 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 Philadelphia 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 Philadelphia that are best for you.

Fly from

Islip

Fly to

Philadelphia

Route

Depart

Return

Price

IslipPhiladelphia

ISP - PHL

ISPPHL

Islip Long Island

Sat 2/7

11:50 am-5:53 pm

1 stop6h 03m

Philadelphia

Mon 2/9

5:17 pm-11:59 am

1 stop18h 42m

$248

IslipPhiladelphia

ISP - PHL

ISPPHL

Islip Long Island

Fri 2/6

2:31 pm-10:37 am

2 stops20h 06m

Philadelphia

Mon 2/9

5:17 pm-11:59 am

1 stop18h 42m

$281

IslipPhiladelphia

ISP - PHL

ISPPHL

Islip Long Island

Mon 2/9

7:20 pm-11:00 pm

1 stop27h 40m

Philadelphia

Fri 2/13

10:59 pm-10:46 am

1 stop11h 47m

$302

IslipPhiladelphia

ISP - PHL

ISPPHL

Islip Long Island

Thu 2/5

7:26 pm-6:11 pm

2 stops22h 45m

Philadelphia

Mon 2/9

5:17 pm-11:59 am

1 stop18h 42m

$313

IslipPhiladelphia

ISP - PHL

ISPPHL

Islip Long Island

Fri 3/27

1:42 pm-10:52 pm

1 stop9h 10m

Philadelphia

Sun 3/29

9:07 pm-10:13 am

1 stop13h 06m

$420

IslipPhiladelphia

ISP - PHL

ISPPHL

Islip Long Island

Fri 4/3

2:31 pm-11:36 pm

1 stop9h 05m

Philadelphia

Sun 4/5

8:18 am-12:41 am

2 stops16h 23m

$424

IslipPhiladelphia

ISP - PHL

ISPPHL

Islip Long Island

Sat 6/20

9:59 am-7:30 pm

1 stop9h 31m

Philadelphia

Sun 7/5

10:00 am-7:45 pm

1 stop9h 45m

$1,133

IslipPhiladelphia

ISP - PHL

ISPPHL

Islip Long Island

Wed 2/25

1:27 pm-11:44 pm

1 stop10h 17m

$465

IslipPhiladelphia

ISP - PHL

ISPPHL

Islip Long Island

Thu 2/26

1:27 pm-11:44 pm

1 stop10h 17m

$490

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/25

Compare providers for flights from Islip to Philadelphia

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Islip to Philadelphia in January.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Islip, New York-Philadelphia 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-Philadelphia flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Islip, New York-Philadelphia flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Islip, New York-Philadelphia 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-Philadelphia 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 Philadelphia

Have a flexible travel schedule? Discover the best time to fly to Philadelphia 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 Philadelphia

What is the cheapest month to book a flight from Islip, New York to Philadelphia?

Currently, April is the cheapest month in which you can book a flight from Islip, New York to Philadelphia (average of $114). Flying from Islip, New York to Philadelphia in January is currently the most expensive (average of $430). 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 Philadelphia. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Islip to Philadelphia 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 Philadelphia?

    Currently, April is the cheapest month in which you can book a flight from Islip, New York to Philadelphia (average of $114). Flying from Islip, New York to Philadelphia in January is currently the most expensive (average of $430). 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 Philadelphia?

Book flights to Philadelphia if you plan to visit one of these locations
Wildwood
Pottstown
Reading
Ocean City
King of Prussia
Cherry Hill
Lewes
Dewey Beach
Ephrata
Camden
Vineland
Milford
Dover
Elkton
Essington
Willow Grove
New Castle
Millville
Newark
Chester

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