$55 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 5/14. 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.
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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$200

Good to know

Low season

April

High season

July

Cheapest flight

$55
Best time to beat the crowds with an average 78% drop in price.
Most popular time to fly and prices are also 38% 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 tips for finding cheap flights to Illinois

  • High season is considered to be January, November and December. The cheapest month to fly from Islip is April.
  • Morning departure is around 13% more expensive than an evening flight, on average*.
*Average of the lowest prices shown in KAYAK’s search results for departures within the next 30 days

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.
6.0
FrontierOverall score based on 3352 reviews
5.7Comfort
6.3Boarding
4.8Food
6.9Crew
4.6Entertainment
Airline reviews

food not having to pay for it, reclining seat would be nice, more leg room, HEAT!!!!!!!

4.0 OkayAnonymous, Feb 2025LAS - JFK
Read more Frontier reviews

food not having to pay for it, reclining seat would be nice, more leg room, HEAT!!!!!!!

An absolutely fraudulent experience. Extremely unprofessional. Terrible in all ways possible. Rude staff, flight attendants, and deceptive "policies."

The worst service , the agents from the counter are really bad . Poor customer service . They didnt help me to get in the flight . I was on line when they close the flight without telling and I couldn’t board the plane . I will like to get my money back ey back because it was their fault. Really bad management , bad manners, bad additud

The check in process was a mess for no reason. I spent an hour waiting in line trying to get them to print my boarding pass and as a result I missed my flight.

The airline used deceptive tactics to charge us more for our trip. Search Frontier Class Action Lawsuit to find out more or read the hundreds of reviews that have nearly identical stories.. don't fly this airline.. you've been warned.

Check in at Philadelphia international was absolutely terrible! I fly 2 to 3 times a month and avoid frontier at all cost and will never fly Frontier again! The night before travel, I tried checking in however, the app was giving me an error, so I went to the desktop, which instructed you that you need to use the app. The next day I presented at the check-in gate after trying at least a half dozen times prior to getting into the airport and continuing to getting the error in the app. I actually had rebooted my phone numerous times and reinstall the app just in case. My phone is only one generation older than the current model. It has no problems completing a frontier flight purchase or any other app issues. There was only three frontier employees working at check-in and a huge line while I was in line I continued to try and check in via the app. As I approach the desk, I was dreading dealing with the agent. He was extremely unprofessional, anti-semantic & very ignorant, and mean to the people in front of me, as well as the people who ended up being behind me. He literally told people “Man I don’t care bout y’all” in his native dialect! Maintaining my composure I approached and explained the situation. To which he replied, you’re gonna have to pay then! I don’t understand. It’s an issue with their app not allowing me to check in! Not my issue! He told me if I pay cash it would be $15, $25 if I pay credit card. I don’t understand a $10 difference for paying with a credit card? I am completely cashless so I continued to try using the app to avoid the $25 fee, Which I still don’t believe that I should be responsible for since it was Frontier’s technical issue!!! I continued to check in via the app a couple more times after he verified I was doing everything right he proceeded to continue to belittle the people behind me. Yelling at them saying I don’t care about you people! I cannot believe that this is the way that businesses would treat its customers! Unfortunately, the black mail with dreadlocks did not have a name tag all he had was a frontier sweater on! For the $25 fee that I ended up getting charged on my credit card. I should’ve just booked originally with Spirit or any other carrier! I have no problem paying fees that I should be responsible for, but when it’s due to a technical failure of a company, the customer should not be responsible for it! I cannot believe that it’s not frontier going out of business!

they delayed my flight which ended up, causing my layover flight to leave without me, resulting in me missing a flight and having to stay overnight in Houston international. I got no compensation other than a flight to my original location only a day later. i’ve never experienced such a unprofessional situation

The flight left over two hours late. They charged me $180 to bring a carry on. There was an error with the spelling of my name and Frontair agent lied that I would need to pay $200 for her to fix the spelling, and pressured me that if I don't do it quick I would lose the flight. I called back and another agent said it costs $75 to fix. All in all, this company is a complete scam.

Very easy with the app to board and staff skills

I took my first and last flight with FRONTIER. The seats are not able to be reclined so it’s not a very comfortable experience when you take a flight of 3 hours or longer. You must pay for your luggage either carry on or check in, so taking all this in consideration at the end what you think you’re saving your paying in services that should be included. Not a beverage in sight. . You’re seriously better off getting on a proper airline such as Delta, AA, United, etc.

Book cheap flights from Islip to Illinois

Recent round-trip flight deals

 
These are the cheapest round-trip flights from Islip to Illinois found on KAYAK in the last 72 hours.
4/7Mon
1 stopFrontier
8h 42mISP-ORD
4/14Mon
1 stopFrontier
9h 49mORD-ISP
$130
4/2Wed
1 stopFrontier
23h 05mISP-ORD
4/5Sat
1 stopFrontier
23h 50mORD-ISP
$135
3/24Mon
1 stopFrontier
22h 50mISP-ORD
3/31Mon
1 stopFrontier
16h 06mORD-ISP
$150
3/22Sat
1 stopFrontier
10h 47mISP-ORD
3/29Sat
1 stopFrontier
12h 06mORD-ISP
$175
5/2Fri
1 stopFrontier
6h 18mISP-STL
5/5Mon
1 stopFrontier
15h 25mSTL-ISP
$200
3/18Tue
1 stopFrontier
13h 01mISP-ORD
3/25Tue
1 stopFrontier
9h 39mORD-ISP
$200
5/5Mon
2 stops
14h 37mISP-ORD
5/8Thu
3 stops
32h 15mORD-ISP
$281
3/24Mon
1 stopSouthwest
4h 30mISP-ORD
3/31Mon
2 stopsSouthwest
15h 00mORD-ISP
$314
5/5Mon
1 stopSouthwest
9h 05mISP-ORD
5/8Thu
2 stopsSouthwest
10h 40mORD-ISP
$328
3/8Sat
1 stopSouthwest
8h 10mISP-ORD
3/10Mon
2 stopsSouthwest
15h 00mORD-ISP
$339

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Recent one-way flight deals

 
Only flying one-way? Below are some of the best one-way flight deals from Islip to Illinois found on KAYAK in the last 72 hours.
5/14Wed
1 stopFrontier
6h 18mISP-STL
$55
3/5Wed
1 stopFrontier
21h 15mISP-ORD
$57
3/3Mon
1 stopFrontier
7h 56mISP-ORD
$67
3/1Sat
1 stopFrontier
10h 25mISP-ORD
$72
4/7Mon
1 stopFrontier
8h 43mISP-ORD
$76
3/13Thu
1 stopFrontier
12h 51mISP-ORD
$81
6/8Sun
1 stopFrontier
10h 35mISP-ORD
$84
3/16Sun
1 stopFrontier
11h 53mISP-ORD
$91
3/3Mon
2 stops
28h 33mISP-ORD
$122
3/5Wed
2 stopsSouthwest
11h 35mISP-ORD
$329

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Last minute flights from Islip to Illinois

Last minute flight, train and bus deals

 
These last-minute flight deals are the cheapest flights found on KAYAK in the last 72 hours for flights from Islip to Illinois that are departing in the next 10 days.
2/25Tue
multi-stopFrontier
12h 54mISP-ORD
2/28Fri
multi-stopFrontier
11h 29mORD-ISP
$144
2/26Wed
multi-stopFrontier
11h 05mISP-ORD
3/4Tue
multi-stopFrontier
6h 49mORD-ISP
$197
2/26Wed
multi-stopFrontier
11h 05mISP-ORD
2/28Fri
multi-stopFrontier
11h 29mORD-ISP
$207
2/25Tue
multi-stopFrontier
12h 54mISP-ORD
2/27Thu
multi-stopFrontier
9h 50mORD-ISP
$227
2/25Tue
multi-stopFrontier
12h 54mISP-ORD
2/27Thu
multi-stopFrontier
9h 50mORD-ISP
$235
2/23Sun
multi-stopFrontier
28h 49mISP-STL
2/26Wed
multi-stopFrontier
17h 51mSTL-ISP
$322
2/24Mon
multi-stopFrontier
7h 56mISP-ORD
2/28Fri
multi-stopFrontier
11h 29mORD-ISP
$420
2/24Mon
multi-stopFrontier
7h 56mISP-ORD
2/27Thu
multi-stopFrontier
6h 33mORD-ISP
$522
2/25Tue
multi-stopSouthwest
7h 30mISP-ORD
2/27Thu
multi-stopSouthwest
8h 45mORD-ISP
$892
2/25Tue
multi-stopSouthwest
11h 35mISP-ORD
2/27Thu
multi-stopSouthwest
11h 00mORD-ISP
$897

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

Information on your arrival and departure airports

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