$99 Cheap flights to Illinois

Chicago is about 99% more popular to visit than any other city in Illinois, according to momondo users. When visiting Chicago, it is recommended to fly into Chicago O'Hare Intl Airport, where you can typically get the cheapest prices and the most convenient travel options into the city.

The closest airport to Magnificent Mile is Chicago O'Hare Intl Airport, and would make for the quickest drive. For those interested in a secondary airport to fly into, consider looking at flights heading to Chicago Midway Airport.

Many visitors who travel to Illinois find themselves making a stop at popular landmarks such as Magnificent Mile, Grant Park, and River North.

Temperatures in Illinois can vary between 23 °F and 73.4 °F based on the time of year. Typically, the coldest month in Illinois will be January, and the warmest month will be July. It is also worth noting that those looking to avoid rain and/or snow should consider traveling to Illinois in January, February, and December, as that is when precipitation is least likely.

United Airlines, American Airlines and Frontier are the top three most popular airlines that fly to Illinois according to our data. United Airlines is the first choice among our users, with 40% of people opting to fly with this airline when traveling to Illinois. Keep in mind that there are 11 different airlines that fly to Illinois on a routine basis, so you have a few additional options to choose from.

The cheapest flight to Illinois recently found on momondo was $29. If you’re unable to find a flight deal this cheap, keep in mind that anything less than $700 is considered a good price for flights to Illinois. $1,066 is the average cost to fly to Illinois, while $32,985 is the most expensive.

Flying to Illinois on a Wednesday or Thursday is your best option since this is when flight prices tend to be at their lowest for the week. The most expensive day of the week to fly to Illinois is on a Sunday.

If you're headed to Illinois, consider flying into Chicago O'Hare Intl airport in Chicago for the best deals, with an average airfare of $29. Alternatively, Quincy Regional airport in Quincy is a close second for cheapest flights to Illinois with an average airfare of $47.

Prices for flights to Illinois are updated daily.

As of July 2026, there are 61 operators available to choose from for flights to Illinois.

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel to Illinois.

The travel and health documents you'll need for your trip to Illinois may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Illinois. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.