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Islip

$224+ 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 8/26. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ISP
ago. 3 — ago. 101
dom. 8/3
dom. 8/10
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 julio 29, 2025.

Round-trip from

$449
(Southwest)

One-way from

$224
(Southwest)

Popular in

December

Cheapest in

January

Average price

$358
From Ontario to Islip Long Island
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One-way flight from Ontario to Islip Long Island
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Highest demand for flights based on searches. 5% potential increase in price ($21 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 July 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 julio 29, 2025.

This Southwest deal was found by Cheapflights users on 7/27. 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.
mié. 8/2710:55 amONT - ISP
1 stop8h 10mSouthwest
sáb. 8/3012:15 pmISP - ONT
1 stop9h 00mSouthwest
Deal found 7/27$449
This Trip.com deal was found by Cheapflights users on 7/28. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/1912:59 amONT - ISP
2 stops19h 42mFrontier
mar. 8/266:05 amISP - ONT
2 stops20h 45mFrontier
Deal found 7/28$602
This United deal was found by Cheapflights users on 7/27. 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.
mié. 8/276:38 pmONT - ISP
2 stops17h 43mMultiple Airlines
sáb. 8/307:30 amISP - ONT
3 stops16h 13mMultiple Airlines
Deal found 7/27$988

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 julio 29, 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

mié. 8/27

10:55 am-10:05 pm

1 stop8h 10m

Islip Long Island

sáb. 8/30

12:15 pm-6:15 pm

1 stop9h 00m

$449

OntarioIslip

ONT - ISP

ONTISP

Ontario

mar. 8/19

12:59 am-11:41 pm

2 stops19h 42m

Islip Long Island

mar. 8/26

6:05 am-11:50 pm

2 stops20h 45m

$602

OntarioIslip

ONT - ISP

ONTISP

Ontario

mié. 8/27

6:38 pm-3:21 pm

2 stops17h 43m

Islip Long Island

sáb. 8/30

7:30 am-8:43 pm

3 stops16h 13m

$988

OntarioIslip

ONT - ISP

ONTISP

Ontario

mar. 8/26

10:55 am-10:05 pm

1 stop8h 10m

$224

OntarioIslip

ONT - ISP

ONTISP

Ontario

mar. 9/9

6:50 pm-1:24 pm

2 stops15h 34m

$428

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/27

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

Reviews of airlines servicing Islip

Get insights into the airlines that provide service to Islip. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Islip. Reviews last updated julio 29, 2025.
Read reviews from past customers who have flown Southwest and Frontier from Ontario to Islip. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,238 reviews

Boarding

8.1

Overall

8.0

Entertainment

7.5

Comfort

8.0

Crew

8.6

Food

7.0

Reviews

1 / 20
10.0
Excellent

Merlyn,Feb 2025

LAX - SMF

New Terminal is neat, lost of stores and places to catch a bite.
Southwest
8.0
Very good
4,238 reviews
Southwest
8.0
Very good
4,238 reviews

Boarding

8.1

Overall

8.0

Entertainment

7.5

Comfort

8.0

Crew

8.6

Food

7.0

Reviews

1 / 20
10.0
Excellent

Merlyn,Feb 2025

LAX - SMF

New Terminal is neat, lost of stores and places to catch a bite.
Frontier
5.9
Fair
3,238 reviews
Southwest
8.0
Very good
4,238 reviews

Boarding

8.1

Overall

8.0

Entertainment

7.5

Comfort

8.0

Crew

8.6

Food

7.0

Reviews

1 / 20
10.0
Excellent

Merlyn,Feb 2025

LAX - SMF

New Terminal is neat, lost of stores and places to catch a bite.

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