Cheap flights from Knoxville to Illinois from $66

The cheapest month to fly to Illinois from Knoxville is in January. Flight prices, which tend to average around $236, are often lower during this time because this is during the off-season. If you aren’t able to travel to Illinois during the month of January, then flying in April is also cheap. Prices for this month can be found on momondo for an average of $263.

The cheapest day to depart from Knoxville to Illinois is on a Friday when prices can be found for as low as $394. Flights from Knoxville to Illinois on a Sunday will generally be more expensive and average around $767. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

Our most recent data shows that the best time of day to fly to Illinois is in the morning. Flights from Knoxville to Illinois during this time can be as low as $488. Flights at noon are often more expensive with an average ticket price of $693.

Fly from Knoxville McGhee Tyson to Chicago Midway for the best Knoxville McGhee Tyson - Illinois flight prices

You are more likely to see cheaper flights to Illinois from Knoxville when booking weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $318 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from Knoxville for as low as $236 on momondo.

There are 4 cabin classes available to choose from on Knoxville to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Allegiant Air, United Airlines, and Southwest are the most popular carriers operating from Knoxville McGhee Tyson to Illinois

American Airlines, United Airlines and Delta are the top three most popular airlines that fly to Illinois from Knoxville according to our data. American Airlines is the first choice among our users, with 46% of people opting to fly with this airline when traveling to Illinois. Keep in mind that there are 4 different airlines that fly to Illinois on a routine basis, so you have a few additional options to choose from.

As of September 2026, there are 25 flights per day flying from Knoxville to Illinois. The most common time of day flights depart is 1:00PM, with 38% of flights taking off in the afternoon.

As of September 2026, 180 flights take off from Knoxville and land in Illinois each week. The most common flight departure day for this route is Fri, with 19% of weekly flights taking off on this day.