$100 Find Cheap Flights from Knoxville 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 Knoxville to Illinois departing on 1/5. 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 Illinois

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

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Chicago
Chicago1 stop$181
Moline
Moline1 stop$321
Peoria
Peoria1 stop$309
Bloomington
Bloomington1 stop$453
St. Louis
St. Louis1 stop$163
Chicago
Chicago1 stop$181
Moline
Moline1 stop$321
Peoria
Peoria1 stop$309
Bloomington
Bloomington1 stop$453
St. Louis
St. Louis1 stop$163

Book Cheap Knoxville 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 Knoxville 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 Knoxville to Illinois

Thu, Jan 8 - Wed, Jan 14
Frontier Logo
4:23 pm - 10:02 am
TYS
-
STL
18h 39m1 stop
Frontier Logo
3:43 pm - 7:23 pm
STL
-
TYS
26h 40m1 stop
$163Frontier
Thu, Jan 8 - Sun, Jan 11
Multiple Airlines Logo
1:39 pm - 2:31 pm
TYS
-
ORD
25h 52m1 stop
Multiple Airlines Logo
8:27 pm - 10:10 am
ORD
-
TYS
12h 43m1 stop
$181Multiple Airlines
Thu, Feb 26 - Mon, Mar 2
American Airlines Logo
4:56 pm - 6:02 pm
TYS
-
ORD
2h 06mnonstop
American Airlines Logo
6:40 pm - 9:23 pm
ORD
-
TYS
1h 43mnonstop
$189American Airlines
Thu, Jan 8 - Sun, Jan 11
Delta Logo
1:00 pm - 5:34 pm
TYS
-
MDW
5h 34m1 stop
Delta Logo
1:28 pm - 8:47 pm
MDW
-
TYS
6h 19m1 stop
$209Delta
Thu, Jan 8 - Sun, Jan 11
Delta Logo
7:30 am - 1:08 pm
TYS
-
ORD
6h 38m1 stop
Delta Logo
1:55 pm - 8:47 pm
ORD
-
TYS
5h 52m1 stop
$209Delta
Sat, Dec 27 - Wed, Dec 31
United Airlines Logo
6:45 am - 7:52 am
TYS
-
ORD
2h 07mnonstop
United Airlines Logo
7:25 am - 10:17 am
ORD
-
TYS
1h 52mnonstop
$219United Airlines
Tue, Dec 30 - Sun, Jan 4
United Airlines Logo
6:45 am - 7:52 am
TYS
-
ORD
2h 07mnonstop
United Airlines Logo
7:48 pm - 10:39 pm
ORD
-
TYS
1h 51mnonstop
$223United Airlines
Fri, May 1 - Sat, May 9
American Airlines Logo
3:03 pm - 4:10 pm
TYS
-
ORD
2h 07mnonstop
American Airlines Logo
3:58 pm - 9:39 pm
ORD
-
TYS
4h 41m1 stop
$224American Airlines
Tue, Apr 7 - Sat, Apr 11
Southwest Logo
8:15 am - 3:50 pm
TYS
-
MDW
8h 35m2 stops
Southwest Logo
6:10 am - 1:20 pm
MDW
-
TYS
6h 10m1 stop
$239Southwest
Tue, Apr 7 - Sat, Apr 11
Southwest Logo
12:50 pm - 8:00 pm
TYS
-
MDW
8h 10m2 stops
Southwest Logo
7:25 am - 6:30 pm
MDW
-
TYS
10h 05m2 stops
$244Southwest
Booking Insights

KAYAK's insights & trends for Knoxville to Illinois flights

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

What is the cheapest Knoxville to Illinois flight route?

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

The cheapest ticket to Illinois from Knoxville found in the last 72 hours was to Belleville, at $131 round-trip. The most popular route is from Knoxville (TYS) to Chicago O'Hare Intl Airport (ORD), and the cheapest round-trip airline ticket found on this route in the last 72 hours was $223.

Can I save money by flying with a layover from Knoxville to Illinois?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $184, prices are generally cheapest when you fly direct.

What is the cheapest month to fly from Knoxville to Illinois?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Knoxville 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 Knoxville to Illinois is February, when tickets cost $214 (return) on average. On the other hand, the most expensive months are December and July, when the average cost of round-trip tickets is $336 and $335 respectively.

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

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

If your flying dates are flexible, you should consider flying to Illinois on a Friday, as we generally find the cheapest rates on that day for this route. On the other hand, Sunday is the most expensive day to fly from Knoxville to Illinois. For your return ticket, we recommend flying on a Saturday and avoiding Mondays for the best deals.

How far in advance should I book a flight from Knoxville to Illinois?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Knoxville to Illinois, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Knoxville to Illinois, you should book around 4 weeks before departure, which saves you about 28% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 21 weeks before departure.

Good to know

Low seasonJune
Cheapest flight$100
Best time to beat the crowds with an average 9% drop in price.
Most popular time to fly and prices are also 20% lower on average.
Flight from Knoxville to Chicago O'Hare Airport

FAQs - booking Illinois flights

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

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Knoxville 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 Knoxville 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 Knoxville 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 Knoxville 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 Knoxville 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 $489 on average. Morning departures are around 10% cheaper than evening flights, on average. The most expensive time of day to fly to Illinois is generally at night, which is peak travel time and where the average cost of a ticket is $842.

Top tips for finding cheap flights to Illinois

  • Looking for a cheap flight? 25% of our users found tickets from Knoxville to the following destinations at these prices or less: Chicago $267 one-way - $337 round-trip

Reviews of the top 4 airlines serving from Knoxville to Illinois

 
See real verified KAYAK customer reviews for airlines flying from Knoxville 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 Knoxville 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.
7.9
DeltaOverall score based on 8008 reviews
8.5Crew
7.9Entertainment
7.9Comfort
8.1Boarding
7.3Food
Airline reviews

Original flight was cancelled and when i was rebooked by the airline, they couldn't seat me in the same type of seat as I had originally booked (went from window/aisle to middle/middle and one was a bulkhead seat, and other wasn't in the same class)

6.0 GoodJeff, Dec 2025
JFK - MIA
Read more Delta reviews

Original flight was cancelled and when i was rebooked by the airline, they couldn't seat me in the same type of seat as I had originally booked (went from window/aisle to middle/middle and one was a bulkhead seat, and other wasn't in the same class)

Lady Pilot was perfect in every way wheels up to wheels down communication, professionalism, excellent on time departure and on time arrival, excellent communication! Fantastic job with Superb attitude!!

The food is terrible. The staff is wonderful. Comfort is good.

Left on time, a bit delayed due to headwinds most of the trip.

I fly Delta all the time, have Platinum Medallion status. But this route seems to have major problems with delays and seems to never leave on time! Have only taken it twice in the last two weeks, and each time it had delays of more than 1 hour... very disappointed!!!!

Good seats in Main cabin, excellent service and excellent landing

My flight was cancelled with no explanation after I had already cleared security. I was given 4 options to rebook, only one being non-stop like I had paid for. I grabbed it. It was 4 plus hours later and then took off even later. Biggest complaint is that I booked early and had an aisle seat. They gave me a "window" seat in front of the exit row, so the seat did not decline. I weigh all of 103 #s and it was tight for me! For what I paid, I feel I was kind of ripped off. I think they should have given me the empty comfort seat for the inconvenience. There was no apology nor any explanation as to why the flight was cancelled. My guess is it benefitted Delta in some way.

Very smooth, on-time, and pleasantly uneventful flight. The team at the gate and on board were professional and genuinely courteous. The pilot kept us well updated throughout, and both takeoff and landing were steady and enjoyable without any drama. Just a good, solid flight. Thank you! 💗

Staff was exceptional! Everyone was kind, professional and friendly making the trip very pleasant. Thank you!

No lunch on a x-country flight scheduled for 10:50 am departure, arrived 5+ hrs later. That requires a black box label before you pay for the tickets. Worst, when I checked in online, it's specifically said that lunch was served on his flight for economy Plus passengers.

It was nice to have gotten up upgraded to first class with a meal on a three hour flight

Very bad! They kept delaying my flight and wouldn’t do anything about it

Door to door, the crew and staff were amazing. It was a stressful travel day with delays, but they were focused on customers and doing what they could to get us to our destinations.

Even though we were delayed, we were able to make our connection

Flight was delayed only slightly before takeoff due to traffic control. However, the flight arrived early to ORD. Good flight. United has been very reliable for me.

Another delayed flight. When the delays exceed the duration of the flight, it’s a problem.

After boarding the plane in Chicago, the passengers were told that there was a technical problem with the plane. Passengers remained on the plane as they tried to fix the problem. After what was probably an hour passengers were told that there was a need to change planes as the problem was not solved. Passengers disembarked and boarded another plane. After taxing to the runway and waiting for takeoff, passengers were told that owing to the thunderstorm the flight was unable to take off but would try and reroute. After some time passengers were told there wasn't enough fuel for the new route and the plane had to return to the gate for additional fuel. after another log delay the flight got underway. On the plane there was food, drinks, ice or entertainment. We were a glass of water, which appeared rationed. Flight arrived about 5 hours late. The pilot was fantastic and communicated with the passengers throughout the ordeal.

Better WiFi. I cannot understand that in 2025, United is so behind on a technology that is now a necessity and still painfully unreliable, slow and keeps disconnecting.

Trip was great. A wild landing in Ottawa with the wind and rain, but the pilot did a great job. Always love flying United.👍

Excellent experience. Starting with the agent at the Premier bag drop who noticed I was very early for my scheduled flight and offered to rebook me on an earlier flight with my seat preference. She would not let me leave the counter until she knew that all of the changes and new boarding pass showed up on my United app. At the gate, the flight boarded quickly such that we departed early and the flight was smooth. We arrived 20 minutes early at ORD and I was able to be home in time for dinner. One of the best flights I've had.

Awful. They won’t help me with anything. I booked on American but they abdicated to Iberia. The ticket was overpriced. Everything negative

I enjoyed the extra leg room compared to other airlines. The first stewards made my daughter’s birthday special by giving her an extra snack. Then the last one coming home from Chicago to Appleton made our night really enjoyable Thanks for making our trip enjoyable

Did not get any refreshments. Crew was very nice but limited. Small seats

Wish a flight with more than 2 hours with some snack rather than just cookie/biscuit.

It was good..clean, comfy seat. Friendly warm welcoming crew. Was able to check my cabin luggage at the gate which I was able to pickup in a decent time from baggage claim. The app gave all updates from delays to baggage claim info. Overall smooth flight.

It was a typical flight. We had a delay which seems to be the normality now. And we had no in flight service due to conditions.

After we landed we sat on the tarmac for 1.5 hours waiting to get to our gate. Ridiculous.

Terrible. Flight delayed for more than 8 hours with only a $12 meal voucher provided for the inconvenience. The airplane did not have breaks on arrival yet they still made us go through the motions and board on time knowing we could not take off then sit for 40+ minutes before having to get of the time. A complete waste of my time. I cannot believe they can stay business with these shenanigans. I’ll avoid this company like the plague moving forward as the lack of accountability is disgraceful.

This was the best 2 flights I have had with American out of SGF. Great crew both flights.

Excellent - explanations were clear staff was nice and flight was comfortable

Clean, friendly, roomy. But check-in from the phone link was terrible. Repeated attempts wouldn’t save at the final step. Just kept spinning! It was very frustrating. Finally, I used the app (vs website link) to check-in which worked very smoothly on the first attempt.

Check in on the web portal was cumbersome! After several attempts I finally got the boarding pass.

Excellent flight and even arrived 23 min early. No entertainment , or wi fi on board, but I downloaded a couple of movies beforehand which kept me entertained. Really like flying Allegiant airlines.

WE were delayed about an hour and never any communications from the employees working the gate. We also were moved to a total of three gates.

I love how they show love to their customers and care about them too.

I liked how when I got on board how fast we ended up taking off but what I truly disliked was how uncomfortable the seats were. There was truly never a time that I could ever get comfortable during both of my flights. The seats could get away during shorter flights but flights 3 hour plus makes it hard to enjoy.

The crew was great and the flight was very smooth. Can’t really judge food since I did not get any because it costs money. The seat was comfortable for what we bought. Thanks!

Crew was great. No entertainment and food and beverage was for purchase only, even water

It was canceled. The flight wasn’t rescheduled, everyone had to figure out their own new arrangements. They said we would get refunded our original fare and receive an additional $150. We received links for $100 only and they expired before we could activate them.

The plane had originated in Las Vegas at 6:30 in the morning and flew to Moline where we boarded. The flight left around 12:30 PM and there were no boxed snacks available and many of the alcoholic beverages were unavailable. I would find it hard to believe that that many of the passengers coming from Las Vegas at 6:30 in the morning, drank and ate that much of the items. I can only come to the conclusion that someone failed to stock the plane for the round-trip. This is a huge revenue failure for the airline and disappointment for the passengers. The flight crew did not seem happy to be there and did not engage with passengers. Allegiant you can do better.

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

Information on your arrival and departure airports