$84 Find Cheap Flights from Islip to Illinois

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Islip to Illinois departing on 9/4. 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

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

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Islip to Illinois, 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 Islip to Illinois, as well as popular online travel agencies
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Cheap Flights from Islip to Illinois

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
St. Louis
St. Louis1 stop$162
St. Louis
St. Louis1 stop$162

Book Cheap Islip to Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Islip to Illinois 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 Islip to Illinois

Sat, Sep 13 - Fri, Sep 19
Frontier Logo
5:05 pm - 1:07 pmISP-STL
21h 02m1 stop
Frontier Logo
1:57 pm - 10:55 amSTL-ISP
19h 58m1 stop
$162Frontier
Find Deal
Thu, Sep 25 - Sun, Sep 28
Frontier Logo
11:40 am - 7:44 pmISP-ORD
9h 04m1 stop
Frontier Logo
8:05 am - 4:27 pmORD-ISP
7h 22m1 stop
$168Frontier
Find Deal
Fri, Sep 26 - Mon, Sep 29
Frontier Logo
5:05 pm - 3:17 pmISP-ORD
23h 12m1 stop
Frontier Logo
8:49 pm - 10:40 amORD-ISP
12h 51m1 stop
$175Frontier
Find Deal
Thu, Sep 18 - Fri, Sep 26
Frontier Logo
11:40 am - 7:44 pmISP-ORD
9h 04m1 stop
Frontier Logo
8:49 pm - 10:55 amORD-ISP
13h 06m1 stop
$184Frontier
Find Deal
Thu, Sep 25 - Sun, Sep 28
Frontier Logo
11:40 am - 7:44 pmISP-ORD
9h 04m1 stop
Frontier Logo
8:05 am - 4:27 pmORD-ISP
7h 22m1 stop
$190Frontier
Find Deal
Tue, Sep 9 - Sat, Sep 13
 Logo
11:25 am - 4:12 pmISP-ORD
29h 47m1 stop
 Logo
5:17 pm - 10:40 amORD-ISP
16h 23m1 stop
Fri, Oct 3 - Mon, Oct 6
Southwest Logo
5:55 am - 4:25 pmISP-STL
11h 30m1 stop
Southwest Logo
4:55 pm - 11:45 pmSTL-ISP
5h 50m1 stop
$299Southwest
Find Deal
Tue, Oct 7 - Sat, Oct 18
Southwest Logo
11:40 am - 4:55 pmISP-STL
6h 15m1 stop
Southwest Logo
7:00 am - 12:10 pmSTL-ISP
4h 10m1 stop
$305Southwest
Find Deal
Tue, Oct 7 - Sat, Oct 18
Southwest Logo
6:00 am - 1:50 pmISP-STL
8h 50m2 stops
Southwest Logo
7:00 am - 12:10 pmSTL-ISP
4h 10m1 stop
$310Southwest
Find Deal
Fri, Oct 3 - Mon, Oct 6
Southwest Logo
11:35 am - 8:35 pmISP-STL
10h 00m2 stops
Southwest Logo
4:55 pm - 11:45 pmSTL-ISP
5h 50m1 stop
$319Southwest
Find Deal
Booking Insights

KAYAK's insights & trends for Islip to Illinois flights

Get data-powered insights and trends into flights from Islip to Illinois to help you find the cheapest flights, the best time to fly and much more.

Which airlines provide the cheapest flights from Islip to Illinois?

The cheapest round-trip price for the route for each airline clicked by KAYAK users in the last 72 hours.

In the past 3 days, the cheapest round-trip tickets from Islip to Illinois were found on Frontier ($162) and Southwest ($299).

Good to know

Low seasonJuly
Cheapest flight$84
Best time to beat the crowds with an average 6% drop in price.
Most popular time to fly with an average 26% increase in price.
Flight from Islip to Chicago

FAQs - booking Illinois flights

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

    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 Islip to Illinois.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Islip to Illinois 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 Islip to Illinois?

    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 from Islip to Illinois with an airline and back with another airline.

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

    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 from Islip to Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • What is the cheapest time of day to fly to Illinois?

    The cheapest time of day to fly to Illinois is generally in the afternoon, when round-trip flights cost $259 on average. Morning departures are around 100% cheaper than evening flights, on average. The most expensive time of day to fly to Illinois is generally in the evening, which is peak travel time and where the average cost of a ticket is $305.

Reviews of the top airline flying from Islip to Illinois

 
See real verified KAYAK customer reviews for airlines flying from Islip to Illinois. 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 Islip to Illinois? 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.
8.0
SouthwestOverall score based on 4241 reviews
8.0Comfort
8.6Crew
8.1Boarding
7.0Food
7.5Entertainment
Airline reviews

AC sub par. WiFi not working correctly. Ac sucked. Seats very narrow.

2.0 MediocreMike, Aug 2025AUS - BWI
Read more Southwest reviews

AC sub par. WiFi not working correctly. Ac sucked. Seats very narrow.

Near 4 hour flight with only 1 service. Had to use call button to request water. Internet and power not working until into flight. Internet would stop working during flight.

Southwest's seats are the least comfortable I have ever sat in.

The cabin was quiet for the redeye flight. The area was clean. The staff was great. The 787 Max was in good condition. Drawbacks were that the seat widths were tight for some passengers. The seat padding was at best average and for a long flight uncomfortable.

Southwest like most American domestic airlines, is a mediocre airline. But it is among the cheapest. Oh well.

My flight was delayed 50 minutes and we were rushed to board to then sit for 15 minutes until the pilot arrived. Unacceptable since we could have waited to board. Also the delayed flight was updated AFTER we boarded to more than the 10 minutes as originally stated.

Other than a bit of a delay, everything was good. Again, the boarding process and picking seats is the only thing I don't enjoy.

If we are going to have to pay for luggage, make it easier to do. Put something on the app during check-in so I don't need to do it at the kiosk. I've done it twice recently and I ended up having to pay at the desk because something went wrong at the kiosk in Tampa.

southwest just starting charging for luggage. hadnt realized it until it was too late. now out $70 when i couldve bought a carry on if i wouldve known. free bags was one of the only reasons i chose southwest over another airline (the other being no assigned seats, which is apparently also being changed). stupid business decision. wont be flying southwest anymore.

The quality of Southwest Airlines continues to degrade each time I fly with them. If it were not for the free luggage, I would probably choose another airline. Their prices are a little bit competitive, but way too high for the quality of the service. Southwest is not unique in this way. Domestic flight in the United States of America has continued to be a lower and lower quality product. Very sad when you compare the quality of domestic airlines to that of many international airlines around the world.

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

Information on your arrival and departure airports

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