ONT - ISP

$203 Find Cheap Flights from Ontario to Islip

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ontario to Islip departing on 9/29. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Islip

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Islip, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Islip, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$405
Southwest
Tue 9/29Wed 10/7
ONT - ISP • 2 stops
Cheapest one-way
$203
Southwest
Tue 9/29
ONT - ISP • 2 stops
Nonstop flights
Not available
There are currently no direct flights between Ontario and Islip. You'll need at least 1 connection.
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Flight Deals

Cheap Flights from Ontario to Islip (ONT-ISP)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to Islip that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Ontario to Islip

Tue, Sep 29 - Wed, Oct 7
Southwest Logo
7:40 am - 9:05 pm
ONT
-
ISP
10h 25m
2 stops
Southwest Logo
6:10 am - 2:30 pm
ISP
-
ONT
11h 20m
2 stops
$405Southwest
Fri, Jun 5 - Tue, Jun 9
Southwest Logo
9:40 pm - 11:35 am
ONT
-
ISP
10h 55m
1 stop
Southwest Logo
6:00 am - 12:05 pm
ISP
-
ONT
9h 05m
1 stop
$592Southwest
Fri, Jun 5 - Tue, Jun 9
Southwest Logo
11:55 pm - 2:50 pm
ONT
-
ISP
11h 55m
2 stops
Southwest Logo
4:40 pm - 11:00 pm
ISP
-
ONT
9h 20m
2 stops
$597Southwest
Booking Insights

Good to know

Cheapest flight$203
Flight from Ontario to Islip

When to book flights from Ontario to Islip

Are your dates flexible? Find out the best times to travel from Ontario to Islip based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Ontario to Islip

  • What is the cheapest flight from Ontario to Islip?

    In the last 3 days, the lowest price for a flight from Ontario to Islip was $203 for a one-way ticket and $405 for a round-trip.

  • Do I need a passport to fly between Ontario and Islip?

    No

  • Which aircraft models fly most regularly from Ontario to Islip?

    We unfortunately don’t have that data for this specific route.

  • How does KAYAK find such low prices on flights from Ontario to Islip?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to Islip.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to Islip?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Islip from Ontario is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Ontario to Islip?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Islip with an airline and back to Ontario with another airline. Booking your flights between Ontario and ISP can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to Islip?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Islip from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airline flying from Ontario to Islip

 
See real verified KAYAK customer reviews for airlines flying from Ontario to Islip. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Ontario to Islip? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.9
SouthwestOverall score based on 4277 reviews
7.0Food
8.0Comfort
8.6Crew
8.1Boarding
7.5Entertainment
Airline reviews

The entire experience from boarding to landing was amazing! The crew were very friendly. Will definitely be back.

10.0 Excellentlarry, Apr 2026
LGB - PHX
Read more Southwest reviews

The entire experience from boarding to landing was amazing! The crew were very friendly. Will definitely be back.

Delayed flight, lack of information, boarding process is a mess as is the carryon luggage causing issues when leaving the plane….just a poor experience.

Comfortable. Easy. No problems. Just wish they had gf options for snacks.

The crew was very kind and made going to Hawaii relaxing and fun to look forward to! Thank you Southwest for a pleasant flight!

Terrible. Even though there’s assigned seating now, they are still the slowest boarding airline of anyone.

It was good from LAX to Phoenix, But the connection in Phoenix to Tulsa was not that great. The staff on both flights were great. The choice of free entertainment was ok nothing to brag about. The 45 min delay because of some electrical issue wasn't great from Phoenix to Tulsa. We sat there with hardly any air, The seat I had was between windows so the side of the plane pushed in on you. My being a bigger man it then made the seating area uncomfortable. The seats on the plane had no power to connect to recharge your phone or anything. I would recommend that they should look into a slot or clamp to hold your phone to enjoy while watching the entertainment choices hands-free. Also make it possible to raise the inner seat by the window be able to raise the arm rest up to make more room for larger people to set more comfortably. I would also say other then that stop price gouging the airfare or nickel and diming everything. Not fair for people having to fly for emergencies and be paying for higher prices due to the season or holidays. Your making your money either way and the cost of flying is still going to be the same regardless if there's 100 people or 200 people.

Had a great flight. Delayed takeoff, but comfortable. Snacks were good.

Southwest was greaat! The most expensive but the least upsetting for those we were flying to see.

Boarding was easy. The seats are small and fairly uncomfortable

The problem with the seat assignments is that there were a lot of rows in the front that were empty but my row at the back was full. Just not so pleasant.

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

Information on your arrival and departure airports

Ontario (ONT)
Islip (ISP)