Cheap flights from Illinois to Denver from $95

The cheapest month to fly to Denver from Illinois is in January. Flight prices, which tend to average around $231, are often lower during this time because this is during the off-season. If you don’t want to visit Denver in January, then you should wait until February to fly from Illinois, when ticket prices are also cheap, with an average price of $257.

The cheapest day to depart on your flight to Denver is on a Friday when prices can be found for as low as $296. This is often the case because there is less demand to fly during this day of the week. The most expensive day to fly to Denver is Monday, with ticket prices averaging around $390.

The cheapest time of day to fly to Denver is in the evening when flights can be purchased for as low as $254. Flights in the afternoon are often more expensive with an average ticket price of $362.

Fly from Chicago O'Hare Intl to Denver Intl for the best Illinois - Denver Intl flight prices

You are more likely to see cheaper flights to Denver from Illinois when booking weeks ahead of your departure date. In general, you can expect to find flights to Denver for around $280 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Denver from Illinois for as low as $238 on momondo.

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

Southwest, United Airlines, and Delta are the most popular carriers operating from Illinois to Denver Intl

United Airlines, American Airlines and Frontier are the top three most popular airlines that fly to Denver from Illinois according to our data. United Airlines is the first choice among our users, with 49% of people opting to fly with this airline when traveling to Denver. Keep in mind that there are 7 different airlines that fly to Denver on a routine basis, so you have a few additional options to choose from.

As of November 2026, 56 flights take off from Illinois and land in Denver each day. The most common flight departure time for this route is 8:00PM, with 33% of daily flights taking off in the afternoon.

As of November 2026, there are 393 flights per week flying from Illinois to Denver. The most common day of the week flights depart is Mon, with 21% of flights taking off on this day.