Cheap flights from Washington, D.C. to Illinois from $58

The cheapest month to fly to Illinois from Washington, D.C. is in January. Flight prices, which tend to average around $293, 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 February is also cheap. Prices for this month can be found on momondo for an average of $303.

The cheapest day to depart from Washington, D.C. to Illinois is on a Thursday when prices can be found for as low as $431. Flights from Washington, D.C. to Illinois on a Monday will generally be more expensive and average around $586. 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 evening. Flights from Washington, D.C. to Illinois during this time can be as low as $433. Flights in the afternoon are often more expensive with an average ticket price of $518.

Fly from Baltimore/Washington to Chicago O'Hare Intl for the best Washington, D.C. - Illinois flight prices

You are more likely to see cheaper flights to Illinois from Washington, D.C. when booking weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $402 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from Washington, D.C. for as low as $302 on momondo.

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

Frontier, Southwest, and United Airlines are the most popular carriers operating from Washington, D.C. to Illinois

United Airlines, American Airlines and Southwest are the top three most popular airlines that fly to Illinois from Washington, D.C. according to our data. United Airlines is the first choice among our users, with 57% of people opting to fly with this airline when traveling to Illinois. Keep in mind that there are 5 different airlines that fly to Illinois on a routine basis, so you have a few additional options to choose from.

91 flights are operational daily from Washington, D.C. to Illinois as of September 2026. The most popular departure time for this route is 5:00PM, with 45% of flights per day taking off at noon.

As of September 2026, 638 flights take off from Washington, D.C. and land in Illinois each week. The most common flight departure day for this route is Fri, with 24% of weekly flights taking off on this day.