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$113+ Cheap flights from Philadelphia to Islip (PHL - ISP)

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 9/16. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — ISP
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheap flight deals from Philadelphia to Islip

Discover tips and strategies to find the most affordable flight options for your journey from Philadelphia (PHL) to Islip (ISP). 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 September 11, 2025.

Round-trip from

$231
(Frontier)

One-way from

$113
(Trip.com)

Popular in

November

Cheapest in

August

Average price

$271
From Philadelphia to Islip Long Island
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One-way flight from Philadelphia to Islip Long Island
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Highest demand for flights based on searches. 18% potential increase in price ($83 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($10 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find flight deals from Philadelphia to Islip

Cheapest flights from Philadelphia to Islip
Explore the most affordable flight options available from Philadelphia to Islip. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

This Frontier deal was found by Cheapflights users on 9/11. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/2210:16 pmPHL - ISP
1 stop12h 24mFrontier
Fri 10/1011:22 amISP - PHL
1 stop6h 10mFrontier
Deal found 9/11$231
This Kiwi.com deal was found by Cheapflights users on 9/10. 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.
Wed 10/89:14 pmPHL - ISP
1 stop23h 28mFrontier
Wed 10/154:58 pmISP - PHL
1 stop18h 28mFrontier
Deal found 9/10$243
This Frontier deal was found by Cheapflights users on 9/10. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/2610:16 pmPHL - ISP
1 stop12h 39mFrontier
Sun 9/289:49 amISP - PHL
1 stop8h 14mFrontier
Deal found 9/10$260
This Frontier deal was found by Cheapflights users on 9/9. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/911:16 amPHL - ISP
1 stop9h 26mFrontier
Thu 10/169:49 amISP - PHL
1 stop8h 20mFrontier
Deal found 9/9$263
This Frontier deal was found by Cheapflights users on 9/10. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/145:01 amPHL - ISP
1 stop11h 26mFrontier
Tue 9/1611:25 amISP - PHL
1 stop9h 46mFrontier
Deal found 9/10$284
This Kiwi.com deal was found by Cheapflights users on 9/10. 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 9/255:15 amPHL - ISP
1 stop29h 25mMultiple Airlines
Mon 9/295:05 pmISP - PHL
1 stop19h 57mMultiple Airlines
Deal found 9/10$288
This Kiwi.com deal was found by Cheapflights users on 9/10. 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.
Wed 10/89:14 pmPHL - ISP
1 stop23h 28mMultiple Airlines
Wed 10/154:58 pmISP - PHL
2 stops22h 56mMultiple Airlines
Deal found 9/10$313
This Kiwi.com deal was found by Cheapflights users on 9/9. 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.
Wed 9/102:07 pmPHL - ISP
1 stop20h 33mMultiple Airlines
Wed 9/1711:35 amISP - PHL
1 stop25h 27mMultiple Airlines
Deal found 9/9$424
This Kiwi.com deal was found by Cheapflights users on 9/9. 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 9/268:43 pmPHL - ISP
1 stop14h 12mMultiple Airlines
Sun 9/285:12 pmISP - PHL
2 stops16h 34mMultiple Airlines
Deal found 9/9$431

Cheapflights Fare Finder

 
Customize your flight search to find flights from Philadelphia to Islip 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 September 11, 2025.
Use the filters below to find and compare flights from Philadelphia to Islip that are best for you.

Fly from

Philadelphia

Fly to

Islip

Route

Depart

Return

Price

PhiladelphiaIslip

PHL - ISP

PHLISP

Philadelphia

Mon 9/22

10:16 pm-10:40 am

1 stop12h 24m

Islip Long Island

Fri 10/10

11:22 am-5:32 pm

1 stop6h 10m

$231

PhiladelphiaIslip

PHL - ISP

PHLISP

Philadelphia

Wed 10/8

9:14 pm-8:42 pm

1 stop23h 28m

Islip Long Island

Wed 10/15

4:58 pm-11:26 am

1 stop18h 28m

$243

PhiladelphiaIslip

PHL - ISP

PHLISP

Philadelphia

Fri 9/26

10:16 pm-10:55 am

1 stop12h 39m

Islip Long Island

Sun 9/28

9:49 am-6:03 pm

1 stop8h 14m

$260

PhiladelphiaIslip

PHL - ISP

PHLISP

Philadelphia

Thu 10/9

11:16 am-8:42 pm

1 stop9h 26m

Islip Long Island

Thu 10/16

9:49 am-6:09 pm

1 stop8h 20m

$263

PhiladelphiaIslip

PHL - ISP

PHLISP

Philadelphia

Thu 9/25

5:15 am-10:40 am

1 stop29h 25m

Islip Long Island

Mon 9/29

5:05 pm-1:02 pm

1 stop19h 57m

$288

PhiladelphiaIslip

PHL - ISP

PHLISP

Philadelphia

Wed 10/8

9:14 pm-8:42 pm

1 stop23h 28m

Islip Long Island

Wed 10/15

4:58 pm-3:54 pm

2 stops22h 56m

$313

PhiladelphiaIslip

PHL - ISP

PHLISP

Philadelphia

Fri 9/26

8:43 pm-10:55 am

1 stop14h 12m

Islip Long Island

Sun 9/28

5:12 pm-9:46 am

2 stops16h 34m

$431

PhiladelphiaIslip

PHL - ISP

PHLISP

Philadelphia

Tue 9/16

2:30 pm-10:40 am

1 stop20h 10m

$113

PhiladelphiaIslip

PHL - ISP

PHLISP

Philadelphia

Fri 10/17

9:53 pm-10:37 am

1 stop12h 44m

$135

PhiladelphiaIslip

PHL - ISP

PHLISP

Philadelphia

Fri 9/19

6:00 am-10:55 am

2 stops28h 55m

$169

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/10

Showing 1-10 of 15 results
1
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Best time to book a flight from Philadelphia to Islip

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

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

Currently, January is the cheapest month in which you can book a flight from Philadelphia to Islip (average of $108). Flying from Philadelphia to Islip in November is currently the most expensive (average of $213). 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.

What is the cheapest time of day to fly from PHL to ISP?

Find hourly flight availability from Philadelphia to Islip. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 11, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Philadelphia to Islip as you normally would.

Related info for your journey

Find useful and relevant information for your journey from Philadelphia to Islip. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Philadelphia to Islip?

    There are many flights that can get you from Philadelphia to Islip in 12h 24m. Fly via Frontier to get the fastest option. There are 129 mi between Philadelphia and Islip.

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

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

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

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

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

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

    Currently, January is the cheapest month in which you can book a flight from Philadelphia to Islip (average of $108). Flying from Philadelphia to Islip in November is currently the most expensive (average of $213). 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 Islip?

Book flights to Islip if you plan to visit one of these locations
Riverhead
Southampton

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Alternative routes for Philadelphia to Islip

See prices for flight routes from nearby airports that may be better suited for you.
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