$98 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 5/1. 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

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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Best Illinois Flight Deals from Islip

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours

St. Louis
St. Louis1 stop$268

Cheap Flight Deals from Islip to Illinois (ISP-USIL)

 
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.

Recent round-trip flight deals from Islip to Illinois

Recommended round-trip deals departing in the coming months from the most popular airlines that fly from Islip to Illinois.
Discover the best prices for you by selecting your travel dates on KAYAK.
Choose your dates
Frontier Logo
6:48 pm - 12:06 amISP-STL
6h 18m1 stop
Frontier Logo
5:45 pm - 10:12 amSTL-ISP
15h 27m1 stop
$268Frontier
Find Deal
Mon, May 5 - Thu, May 8
Southwest Logo
5:05 am - 11:50 amISP-ORD
7h 45m1 stop
Southwest Logo
1:50 pm - 10:55 pmORD-ISP
8h 05m1 stop
$292Southwest
Find Deal
Mon, Jun 9 - Tue, Jun 10
Frontier Logo
9:00 am - 4:18 pmISP-ORD
8h 18m1 stop
Frontier Logo
7:30 am - 6:15 pmORD-ISP
9h 45m1 stop
$298Frontier
Find Deal
Thu, Apr 17 - Sat, Apr 19
Frontier Logo
9:04 pm - 10:20 amISP-ORD
14h 16m1 stop
Frontier Logo
9:44 am - 8:44 amORD-ISP
22h 00m1 stop
$305Frontier
Find Deal
Sat, Apr 12 - Tue, Apr 15
Frontier Logo
4:31 pm - 12:36 amISP-ORD
9h 05m1 stop
Frontier Logo
7:30 am - 6:15 pmORD-ISP
9h 45m1 stop
$308Frontier
Find Deal
Fri, Apr 11 - Sat, Apr 12
Southwest Logo
6:05 am - 5:55 pmISP-ORD
12h 50m2 stops
Southwest Logo
1:50 pm - 10:45 pmORD-ISP
7h 55m1 stop
$314Southwest
Find Deal
Wed, Aug 6 - Mon, Aug 11
Frontier Logo
9:40 pm - 8:05 amISP-ORD
11h 25m1 stop
Frontier Logo
6:55 am - 3:33 pmORD-ISP
7h 38m1 stop
$318Frontier
Find Deal
Thu, May 15 - Mon, May 19
Southwest Logo
5:40 am - 11:45 amISP-STL
7h 05m2 stops
Southwest Logo
6:00 pm - 11:05 pmSTL-ISP
4h 05m1 stop
$324Southwest
Find Deal
Mon, May 5 - Thu, May 8
Frontier Logo
8:26 pm - 12:36 amISP-ORD
29h 10m1 stop
Frontier Logo
9:13 am - 7:41 pmORD-ISP
9h 28m1 stop
$328Frontier
Find Deal
Fri, Jun 6 - Sun, Jun 8
 Logo
10:44 am - 5:15 pmISP-STL
31h 31m2 stops
 Logo
10:10 am - 3:19 pmSTL-ISP
28h 09m3 stops
Mon, May 5 - Thu, May 8

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.

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

The average price for all round-trip flights from Islip to Illinois depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.
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.

Good to know

Low season

April

High season

July

Cheapest flight

$98
Best time to beat the crowds with an average 9% drop in price.
Most popular time to fly and prices are also 39% lower on average.
Flight from Islip to St. Louis

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.

See more FAQs

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 4277 reviews
8.0Comfort
7.6Entertainment
8.2Boarding
8.7Crew
7.1Food
Airline reviews

Boarding process, crew were good. But the seats were so uncomfortable that was all I could focus on. I literally had to sit forward so that all 3 of us could fit in row. I will try to avoid Southwest in the future for any flights over 60 minutes.

6.0 GoodCarolynn, Mar 2025KOA - SMF
Read more Southwest reviews

Boarding process, crew were good. But the seats were so uncomfortable that was all I could focus on. I literally had to sit forward so that all 3 of us could fit in row. I will try to avoid Southwest in the future for any flights over 60 minutes.

1.5 hour delay, poor service, no compassion from the crew. Terrible experience

Great flight, 47 passengers on a 180 seat plane. Stewardess was pleasant and cheerful.

Short flight with plenty of open seats. Drinks and snacks were still provided even on such a short flight. <1 hr

I liked the crew member who gave flight instructions on "in case of a problem:. The seats are so small that only a young teenager could sit in middle seat.

Great experience flying Southwest. The crew was really kind and helpful, and very friendly with our toddler.

Very good. Sad to learn Southwest is going start to charge for bags

Our flight was diverted from being a non-stop to getting within 150 miles and requiring another plane. We heard 4 or 5 different versions from SW as to why we had to stop, then wait for a replacement plane. Five hour delay, weather did not come up as a single excuse.... communication was not clear and well explained. No one really took charge!

My flight to Chicago left and landed early. My return flight left two minutes late and arrived 2 minutes late. My seat selections were ideal! There were no snacks going to Chicago and no snacks on the return trip. There are no charging outlets on board.

WiFi on the flight was not working. Thus, entertainment options were limited.

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

Information on your arrival and departure airports

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