In terms of precipitation, rainfall in Islip, New York ranges from 3.3 - 4.4 inches per month. March is typically the wettest month, when rainfall can reach 4.4 in. February is typically the driest time to visit Islip, New York when rainfall is around 3.3 in.

If weather is an important factor for your trip to Islip, New York, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 30.2 F).

What are the most popular routes from Region of Ontario to Islip, New York?

The most popular flight routes from Region of Ontario to Islip, New York are Montreal Pierre Elliott Trudeau Intl - Islip Long Island, Ottawa - Islip Long Island and Toronto Pearson Intl - Islip Long Island.

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

When flying from Region of Ontario to Islip, New York, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

What airport do you fly into for flights to Islip from Ontario?

Most people fly into Islip Long Island (ISP) if they book a flight to Islip from Ontario. Long Island is conveniently located just 7.2 mi from Islip’s city center.

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.

$417+ Flights from Ontario to Islip, NY

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Cheap 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 décembre 15, 2025.

sam. 12/207:10 amYYZ - ISP

1 stop29h 59mMultiple Airlines

dim. 1/118:40 pmISP - YYZ

1 stop27h 31mMultiple Airlines

Deal found 12/12

$506

sam. 12/207:10 amYYZ - ISP

1 stop29h 59mMultiple Airlines

mar. 12/238:22 pmISP - YYZ

2 stops22h 34mMultiple Airlines

Deal found 12/13

$630

Last-minute flights from Ontario to Islip
Discover last-minute flight deals from Ontario to Islip. Data last updated décembre 15, 2025 and is based on user searches.

sam. 12/207:10 amYYZ - ISP

1 stop29h 59mMultiple Airlines

dim. 1/118:40 pmISP - YYZ

1 stop27h 31mMultiple Airlines

Deal found 12/12

$506

sam. 12/207:10 amYYZ - ISP

1 stop29h 59mMultiple Airlines

mar. 12/238:22 pmISP - YYZ

2 stops22h 34mMultiple Airlines

Deal found 12/13

$630

One-way flights from Ontario to Islip
Search for one-way flight options from Ontario to Islip. Find affordable one-way fares based on user searches. Data last updated décembre 15, 2025.

mer. 12/3110:15 amYUL - ISP

3 stops28h 55mMultiple Airlines

Deal found 12/14

$417

Find flight deals from Ontario to Islip

Most accurate provider	Justfly.com 3 stars
Most trusted provider	Justfly.com 3 stars
Popular in	December
Cheapest in	May
Average price	$271

Provider with most accurate pricing for Toronto (YTO)-New York (NYC) flight deals.

Search Deals

Provider most trusted by Cheapflights users for Toronto (YTO)-New York (NYC) flights.

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Highest demand for flights based on searches. 9% potential increase in price ($23 potential increase over avg. RT price).

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Cheapest flight prices on average. 2% potential price decrease ($5 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in December 2025

Search Deals

Fly from

Fly to

Route

Depart

Return

Price

MontrealIslip

YUL - ISP

YULISP

Montreal Pierre Elliott Trudeau Intl

mer. 12/31

10:15 am-3:10 pm

3 stops28h 55m

$417

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/14

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 Region of Ontario to Islip, New York?

Currently, May is the cheapest month in which you can book a flight from Region of Ontario to Islip, New York (average of $83). Flying from Region of Ontario to Islip, New York in December is currently the most expensive (average of $176). 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

What airport do you fly into for flights to Islip from Ontario?
Most people fly into Islip Long Island (ISP) if they book a flight to Islip from Ontario. Long Island is conveniently located just 7.2 mi from Islip’s city center.
What are the most popular routes from Region of Ontario to Islip, New York?
The most popular flight routes from Region of Ontario to Islip, New York are Montreal Pierre Elliott Trudeau Intl - Islip Long Island, Ottawa - Islip Long Island and Toronto Pearson Intl - Islip Long Island.
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 Region of Ontario to Islip, New York?
Currently, May is the cheapest month in which you can book a flight from Region of Ontario to Islip, New York (average of $83). Flying from Region of Ontario to Islip, New York in December is currently the most expensive (average of $176). 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.

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$417+ Cheap flights from Ontario to Islip, NY (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 12/31. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Ontario to Islip with Cheapflights

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Cheap flight deals from Ontario to Islip

Cheapest flights from Ontario to IslipExplore 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 décembre 15, 2025.

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 décembre 15, 2025.

Find flight deals from Ontario to Islip

Keep the following information in mind while searching for Ontario to Islip flight deals. Data was last updated décembre 15, 2025.

Most accurate provider

Most trusted provider

Popular in

Cheapest in

Average price

Cheapflights Fare Finder

Use the filters below to find and compare flights from Ontario to Islip that are best for you.

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.

Cheapflights Insights

Everything you need to know about your flight from Ontario to Islip

What is the cheapest month to book a flight from Region of Ontario to Islip, New York?

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.

What airport do you fly into for flights to Islip from Ontario?

What are the most popular routes from Region of Ontario to Islip, New York?

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

How can I find direct flights from Ontario to Islip?

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

What is the cheapest month to book a flight from Region of Ontario to Islip, New York?

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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 décembre 15, 2025.