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Islip

$239+ Cheap flights from Ontario to Islip, NY (ONT - 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 12/19. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ISP
Nov 27 — Dec 41
Thu 11/27
Thu 12/4
1 adult, Economy
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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 October 28, 2025.

This Southwest deal was found by Cheapflights users on 10/27. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/610:50 amONT - ISP
1 stop10h 00mSouthwest
Sun 11/911:05 amISP - ONT
1 stop9h 10mSouthwest
Deal found 10/27$872
This Expedia deal was found by Cheapflights users on 10/27. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/106:11 pmONT - ISP
2 stops13h 53mMultiple Airlines
Thu 11/1312:40 pmISP - ONT
2 stops14h 16mMultiple Airlines
Deal found 10/27$1,255
This United deal was found by Cheapflights users on 10/27. 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.
Thu 10/307:00 amONT - ISP
2 stops9h 45mMultiple Airlines
Sun 11/212:40 pmISP - ONT
2 stops26h 53mMultiple Airlines
Deal found 10/27$1,520

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 October 28, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$1,255
(Expedia)

One-way from

$239
(Southwest)

Popular in

December

Cheapest in

January

Average price

$365
Provider with most accurate pricing for Ontario-Islip Long Island flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Islip Long Island flights.
Search Deals
From Ontario to Islip Long Island
Search Deals
One-way flight from Ontario to Islip Long Island
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($16 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($7 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals

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 October 28, 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

Mon 11/10

6:11 pm-11:04 am

2 stops13h 53m

Islip Long Island

Thu 11/13

12:40 pm-11:56 pm

2 stops14h 16m

$1,255

OntarioIslip

ONT - ISP

ONTISP

Ontario

Fri 12/19

10:10 am-11:55 pm

2 stops10h 45m

$239

OntarioIslip

ONT - ISP

ONTISP

Ontario

Fri 12/19

6:00 am-5:55 pm

3 stops32h 55m

$362

OntarioIslip

ONT - ISP

ONTISP

Ontario

Mon 12/15

7:33 pm-11:04 am

2 stops12h 31m

$460

OntarioIslip

ONT - ISP

ONTISP

Ontario

Thu 12/4

7:33 pm-11:04 am

2 stops12h 31m

$460

OntarioIslip

ONT - ISP

ONTISP

Ontario

Thu 12/11

7:33 pm-11:04 am

2 stops12h 31m

$460

OntarioIslip

ONT - ISP

ONTISP

Ontario

Tue 1/6

7:19 pm-11:04 am

2 stops12h 45m

$474

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/26

Compare providers for flights from Ontario to Islip

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 Ontario to Islip in October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice 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 Ontario-Islip, New York flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Ontario-Islip, New York flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Ontario-Islip, New York flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Ontario-Islip, New York flights, Cheapflights users trust eDreams the most. eDreams 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 Ontario-Islip, New York 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 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, New York?

Currently, June is the cheapest month in which you can book a flight from Ontario to Islip, New York (average of $78). Flying from Ontario to Islip, New York in December is currently the most expensive (average of $177). 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.

  • 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, New York?

    Currently, June is the cheapest month in which you can book a flight from Ontario to Islip, New York (average of $78). Flying from Ontario to Islip, New York in December is currently the most expensive (average of $177). 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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