Cheap flights from San José to Illinois from $140

The cheapest month to fly to Illinois from San José is in January. Flight prices, which tend to average around $369, 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 October is also cheap. Prices for this month can be found on momondo for an average of $412.

The cheapest day to depart from San José to Illinois is on a Tuesday when prices can be found for as low as $429. Flights from San José to Illinois on a Sunday will generally be more expensive and average around $579. 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 at noon. Flights from San José to Illinois during this time can be as low as $465. Flights in the morning are often more expensive with an average ticket price of $468.

Fly from San José Juan Santamaria Intl to Chicago O'Hare Intl for the best San José Juan Santamaria Intl - Illinois flight prices

You are more likely to see cheaper flights to Illinois from San José when booking weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $454 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from San José for as low as $374 on momondo.

There are 3 cabin classes available to choose from on San José Juan Santamaria Intl to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Frontier, Spirit Airlines, and Southwest are the most popular carriers operating from San José Juan Santamaria Intl to Illinois

American Airlines, United Airlines and Copa Airlines are the top three most popular airlines that fly to Illinois from San José according to our data. American Airlines is the first choice among our users, with 45% of people opting to fly with this airline when traveling to Illinois. Keep in mind that there are 6 different airlines that fly to Illinois on a routine basis, so you have a few additional options to choose from.

As of March 2026, there are 1 flights per day flying from San José to Illinois. The most common time of day flights depart is 6:00AM, with 50% of flights taking off at noon.

The number of flights available between San José and Illinois is 7 per week as of March 2026. The most frequent departure day is Mon, with 14% of weekly flights leaving on this day.