$166 Find Cheap Flights from Sioux City 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 Sioux City to Illinois departing on 10/4. 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 Sioux City 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 Sioux City to Illinois, as well as popular online travel agencies
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Flight Deals

Book Cheap Sioux City 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 Sioux City 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 Sioux City to Illinois

Fri, Dec 26 - Tue, Dec 30
United Airlines Logo
7:50 am - 9:45 amSUX-ORD
1h 55mnonstop
United Airlines Logo
9:18 pm - 11:15 pmORD-SUX
1h 57mnonstop
$265United Airlines
Find Deal
Tue, Oct 14 - Wed, Oct 15
United Airlines Logo
7:50 am - 9:41 amSUX-ORD
1h 51mnonstop
United Airlines Logo
9:08 pm - 11:00 pmORD-SUX
1h 52mnonstop
$326United Airlines
Find Deal
Fri, Sep 19 - Mon, Sep 22
United Airlines Logo
6:48 pm - 4:45 pmSUX-ORD
21h 57m2 stops
United Airlines Logo
9:05 pm - 10:57 pmORD-SUX
1h 52mnonstop
$383United Airlines
Find Deal
Fri, Sep 19 - Mon, Sep 22
United Airlines Logo
6:48 pm - 2:55 pmSUX-ORD
20h 07m1 stop
United Airlines Logo
9:05 pm - 10:57 pmORD-SUX
1h 52mnonstop
$401United Airlines
Find Deal
Sun, Aug 31 - Thu, Sep 4
United Airlines Logo
7:49 am - 9:40 amSUX-ORD
1h 51mnonstop
United Airlines Logo
9:05 pm - 10:57 pmORD-SUX
1h 52mnonstop
$416United Airlines
Find Deal
Tue, Oct 14 - Wed, Oct 15
United Airlines Logo
7:50 am - 9:41 amSUX-ORD
1h 51mnonstop
United Airlines Logo
7:25 am - 6:14 pmORD-SUX
10h 49m2 stops
$417United Airlines
Find Deal
Fri, Sep 19 - Mon, Sep 22
United Airlines Logo
6:48 pm - 6:55 pmSUX-ORD
24h 07m2 stops
United Airlines Logo
9:50 pm - 6:13 pmORD-SUX
20h 23m2 stops
$430United Airlines
Find Deal
Sat, Aug 30 - Mon, Sep 1
United Airlines Logo
6:48 pm - 8:10 pmSUX-ORD
25h 22m2 stops
United Airlines Logo
9:05 pm - 10:57 pmORD-SUX
1h 52mnonstop
$444United Airlines
Find Deal
Tue, Oct 14 - Wed, Oct 15
United Airlines Logo
7:50 am - 9:41 amSUX-ORD
1h 51mnonstop
United Airlines Logo
9:44 pm - 6:14 pmORD-SUX
20h 30m1 stop
$446United Airlines
Find Deal
Fri, Sep 19 - Mon, Sep 22
United Airlines Logo
6:48 pm - 7:57 pmSUX-ORD
25h 09m1 stop
United Airlines Logo
7:19 am - 6:13 pmORD-SUX
10h 54m2 stops
$453United Airlines
Find Deal
Booking Insights

KAYAK's insights & trends for Sioux City to Illinois flights

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

What is the cheapest Sioux City to Illinois flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Illinois from Sioux City found in the last 72 hours was to Chicago, at $253 round-trip. The most popular route is from Sioux City (SUX) to Chicago O'Hare Intl Airport (ORD), and the cheapest round-trip airline ticket found on this route in the last 72 hours was $253.

What is the cheapest month to fly from Sioux City to Illinois?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Sioux City to Illinois, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Sioux City to Illinois is September, when tickets cost $260 (return) on average. On the other hand, the most expensive months are May and August, when the average cost of round-trip tickets is $441 and $397 respectively.

What’s the cheapest day of the week to fly from Sioux City to Illinois?

The average price of all round-trip flights from Sioux City to Illinois clicked on KAYAK for each day over the last 12 months.

For Sioux City to Illinois, Thursday is the cheapest day to fly on average and Sunday is the most expensive. Flying from Illinois back to Sioux City, the best deals are generally found on Friday, with Monday being the most expensive.

Good to know

Low seasonSeptember
Cheapest flight$166
Best time to beat the crowds with an average 18% drop in price.
Most popular time to fly and prices are also 17% lower on average.
Flight from Sioux City to Chicago

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from Sioux City 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 Sioux City to Illinois.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Sioux City 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 Sioux City 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 Sioux City 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 Sioux City 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 Sioux City 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 morning, when round-trip flights cost $469 on average. The most expensive time of day to fly to Illinois is generally in the morning, which is peak travel time and where the average cost of a ticket is $469.

Top tips for finding cheap flights to Illinois

  • Looking for a cheap flight? 25% of our users found tickets from Sioux City to the following destinations at these prices or less: Chicago $223 one-way - $354 round-trip

Reviews of the top airline flying from Sioux City to Illinois

 
See real verified KAYAK customer reviews for airlines flying from Sioux City 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 Sioux City 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.
7.4
United AirlinesOverall score based on 8925 reviews
6.6Food
7.7Boarding
7.3Comfort
8.1Crew
7.1Entertainment
Airline reviews

Flight attendant in first class gave poor service (like he didn't want to be there) and food was awful. We sat waiting for gate upon arrival over 45 mins.

2.0 MediocreAnonymous, Aug 2025RSW - ORD
Read more United Airlines reviews

Flight attendant in first class gave poor service (like he didn't want to be there) and food was awful. We sat waiting for gate upon arrival over 45 mins.

Weather delay in Chicago?. No sense of urgency to make connection in Chicago for our connecting flight that wasn't delayed. Connection was missed.

Overall it was good. I missed my connection but I was put on another flight.

Overall a very poor experience - booked premium economy tickets but due to last minute flight delays , all my itinery went for a toss and had to fly economy class with no access to lounge or any compensation by united airlines to make up for the flight delays . i had expected better experience than that from united.

It was fine, definitely older planes with no charging or anything. There’s no entertainment set up on board, but it is nice that they allow you to access the in flight entertainment from your phone without having to pay for the Wi-Fi and they do offer free texting.

I liked that the flight was nonstop from ORD to CIU for $200 round trip.

The schedule to Moline changed 5 times. The gate changed 6 times. That is a pathetic way to run an airline. No wonder that no one in our company flies on United Express to or from Moline. Changes happen most of the time. I learned my lesson on this trip…never again!

While the staff was pleasant and helpful, the following observations are for your awareness. There was some delay on the tarmac on take off and landing. The paid lunch/food offerings were limited. Entertainment was only available on WiFi at a cost.

The first flight was better in terms of the aircraft.

Smooth flight. Boarding was chaotic. Could not hear the gate agent over the intercom. People were lined up in the wrong lines. Groups one and two were told to board through line one and group 3 through line 2. All very confusing. Once in the air, the flight was smooth. There was no entertainment option on this aircraft, even though it was a larger aircraft.

Everything you need to know for your flight from Sioux City to Illinois

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