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Islip

$310+ Cheap flights from Ontario to Islip (ONT - ISP)

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 10/24. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ISP
oct. 11 — oct. 181
sáb. 10/11
sáb. 10/18
1 adult, Economy
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Cheap flight deals from Ontario to Islip

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) 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 septiembre 11, 2025.

Round-trip from

$310
(Frontier)

Popular in

December

Cheapest in

January

Average price

$297
From Ontario to Islip Long Island
Search Deals
Highest demand for flights based on searches. 6% potential increase in price ($24 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($8 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 Ontario to Islip

Cheapest flights from Ontario to Islip
Explore the most affordable flight options available from Ontario to Islip. Find the lowest fares from popular airlines and budget airlines, with prices last updated on septiembre 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.
vie. 10/2412:32 pmONT - ISP
2 stops19h 05mFrontier
dom. 10/269:47 pmISP - ONT
2 stops21h 41mFrontier
Deal found 9/11$310
This Gotogate 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 10/176:53 amONT - ISP
2 stops24h 44mFrontier
sáb. 10/2512:38 pmISP - ONT
2 stops14h 12mFrontier
Deal found 9/10$336
This Booking.com 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 9/188:59 pmONT - ISP
2 stops40h 24mFrontier
mar. 9/2311:25 amISP - ONT
2 stops46h 58mFrontier
Deal found 9/11$376
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.
jue. 10/98:34 amONT - ISP
2 stops21h 30mFrontier
sáb. 10/1812:38 pmISP - ONT
2 stops14h 12mFrontier
Deal found 9/10$380
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.
dom. 9/147:15 pmONT - ISP
2 stops18h 12mFrontier
dom. 9/219:49 amISP - ONT
2 stops11h 46mFrontier
Deal found 9/11$387
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.
jue. 9/113:43 pmONT - ISP
2 stops14h 21mFrontier
jue. 9/1811:40 amISP - ONT
2 stops23h 13mFrontier
Deal found 9/10$650
This United 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 United is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 9/146:38 pmONT - ISP
2 stops15h 46mMultiple Airlines
mar. 9/1611:53 amISP - ONT
2 stops12h 32mMultiple Airlines
Deal found 9/10$957
This Cheapflightsfares 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/207:43 pmONT - ISP
2 stops12h 15mMultiple Airlines
mié. 11/122:19 pmISP - ONT
2 stops12h 37mMultiple Airlines
Deal found 9/9$1,030
This Cheapflightsfares 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 10/247:43 pmONT - ISP
2 stops12h 15mMultiple Airlines
sáb. 11/12:19 pmISP - ONT
2 stops12h 37mMultiple Airlines
Deal found 9/10$1,044
This Cheapflightsfares 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/207:43 pmONT - ISP
2 stops12h 15mMultiple Airlines
sáb. 10/252:19 pmISP - ONT
2 stops12h 30mMultiple Airlines
Deal found 9/11$1,105
This United 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 United is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 9/205:10 amONT - ISP
2 stops11h 51mMultiple Airlines
jue. 9/2511:53 amISP - ONT
2 stops12h 31mMultiple Airlines
Deal found 9/11$1,120
This Cheapflightsfares 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 10/227:43 pmONT - ISP
2 stops12h 15mMultiple Airlines
mié. 10/292:19 pmISP - ONT
2 stops12h 37mMultiple Airlines
Deal found 9/10$1,139

Cheapflights Fare Finder

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

Fly from

Ontario

Fly to

Islip

Route

Depart

Return

Price

OntarioIslip

ONT - ISP

ONTISP

Ontario

vie. 10/24

12:32 pm-10:37 am

2 stops19h 05m

Islip Long Island

dom. 10/26

9:47 pm-4:28 pm

2 stops21h 41m

$310

OntarioIslip

ONT - ISP

ONTISP

Ontario

vie. 10/17

6:53 am-10:37 am

2 stops24h 44m

Islip Long Island

sáb. 10/25

12:38 pm-11:50 pm

2 stops14h 12m

$336

OntarioIslip

ONT - ISP

ONTISP

Ontario

jue. 10/9

8:34 am-9:04 am

2 stops21h 30m

Islip Long Island

sáb. 10/18

12:38 pm-11:50 pm

2 stops14h 12m

$380

OntarioIslip

ONT - ISP

ONTISP

Ontario

lun. 10/20

7:43 pm-10:58 am

2 stops12h 15m

Islip Long Island

mié. 11/12

2:19 pm-11:56 pm

2 stops12h 37m

$1,030

OntarioIslip

ONT - ISP

ONTISP

Ontario

vie. 10/24

7:43 pm-10:58 am

2 stops12h 15m

Islip Long Island

sáb. 11/1

2:19 pm-11:56 pm

2 stops12h 37m

$1,044

OntarioIslip

ONT - ISP

ONTISP

Ontario

lun. 10/20

7:43 pm-10:58 am

2 stops12h 15m

Islip Long Island

sáb. 10/25

2:19 pm-11:49 pm

2 stops12h 30m

$1,105

OntarioIslip

ONT - ISP

ONTISP

Ontario

mié. 10/22

7:43 pm-10:58 am

2 stops12h 15m

Islip Long Island

mié. 10/29

2:19 pm-11:56 pm

2 stops12h 37m

$1,139

OntarioIslip

ONT - ISP

ONTISP

Ontario

lun. 10/20

7:43 pm-10:58 am

2 stops12h 15m

Islip Long Island

lun. 10/27

2:19 pm-11:56 pm

2 stops12h 37m

$1,318

OntarioIslip

ONT - ISP

ONTISP

Ontario

mar. 10/21

7:43 pm-10:58 am

2 stops12h 15m

$390

OntarioIslip

ONT - ISP

ONTISP

Ontario

lun. 10/20

7:43 pm-10:58 am

2 stops12h 15m

$425

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/11

Showing 1-10 of 18 results
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Best time to book a flight from Ontario to Islip

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

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

Currently, January is the cheapest month in which you can book a flight from Ontario to Islip (average of $108). Flying from Ontario 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.

Related info for your journey

Find useful and relevant information for your journey from Ontario 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 Ontario to Islip?

    For as low as $310, Frontier can have you in Islip from Ontario in 19h 05m. The distance from Ontario to Islip is about 2457 mi.

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

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

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

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

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

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

    Currently, January is the cheapest month in which you can book a flight from Ontario to Islip (average of $108). Flying from Ontario 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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