Cheap flights from Colorado to Illinois from $63
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Colorado to Illinois departing on 7/4. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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How to get the cheapest flight ticket from Colorado to Illinois
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to Illinois?
The cheapest month to fly to Illinois from Colorado is in September. Flight prices, which tend to average around $148, 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 September, then flying in October is also cheap. Prices for this month can be found on momondo for an average of $157.
What is the cheapest day to depart on your flight to Illinois?
The cheapest day to depart from Colorado to Illinois is on a Friday when prices can be found for as low as $290. Flights from Colorado to Illinois on a Sunday will generally be more expensive and average around $511. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.
What is the cheapest time of day to depart on your flight to Illinois?
Our most recent data shows that the best time of day to fly to Illinois is in the evening. Flights from Colorado to Illinois during this time can be as low as $186. Flights at noon are often more expensive with an average ticket price of $649.
What is the cheapest Colorado to Illinois flight route?
Fly from Denver Intl to Chicago O'Hare Intl for the best Colorado - Illinois flight prices
How far in advance should I book a flight to Illinois?
You are more likely to see cheaper flights to Illinois from Colorado when booking 5 weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $225 when searching 5 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from Colorado for as low as $187 on momondo.
What cabin class options are available on Colorado to Illinois flights?
There are 4 cabin classes available to choose from on Colorado to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Colorado to Illinois?
Allegiant Air, Frontier, and American Airlines are the most popular carriers operating from Colorado to Illinois
What airlines fly to Illinois?
United Airlines, Frontier and American Airlines are the top three most popular airlines that fly to Illinois from Colorado according to our data. United Airlines is the first choice among our users, with 35% 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.
How many flights depart from Colorado to Illinois on average per day?
As of June 2025, 95 flights take off from Colorado and land in Illinois each day. The most common flight departure time for this route is 2:00PM, with 50% of daily flights taking off in the afternoon.
How many flights depart from Colorado to Illinois on average per week?
The number of flights available between Colorado and Illinois is 669 per week as of June 2025. The most frequent departure day is Mon, with 17% of weekly flights leaving on this day.
Cheap Colorado to Illinois flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Colorado to Illinois
When did momondo last update prices for flights from Colorado to Illinois?
Prices for flights from Colorado to Illinois are updated daily.
How many operators does momondo search for flights from Colorado to Illinois?
As of June 2025, there are 5 operators available to choose from for flights from Colorado to Illinois.
How old do you have to be to fly from Colorado 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 from Colorado to Illinois.
What documentation or ID do you need to fly to Illinois?
The required travel and health documents for your Illinois trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Illinois. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular plane model from Colorado to Illinois?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Colorado to Illinois is Airbus A321neo (11.83% of total bookings). The next most popular plane models are Boeing 737-800 (10.49%), Boeing 737-800 Passenger/BBJ2 (winglets) (10.33%), and Boeing 737 MAX 8 (9.39%).
Best airlines flying from Colorado to Illinois
Compare and see reviews for airlines that fly from Colorado to Illinois with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $54 | Free Cancellation | Rating 5.9 3,301 reviews | |||
| PriceFrom $82 | Free Cancellation | Rating 7.3 722 reviews | |||
| PriceFrom $150 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $155 | Free Cancellation | Rating 8.0 4,280 reviews | |||
| PriceFrom $158 | Free Cancellation | Rating 7.4 8,809 reviews |
Why use momondo?
Why should I use momondo to find a flight deal from Colorado to Illinois?
momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Colorado to Illinois. Millions of users trust and use momondo every year so you are in good hands.
Can I find flights from Colorado to Illinois with flexible booking policies on momondo?
Flights from Colorado to Illinois with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.
How can momondo help me find flights from Colorado to Illinois?
Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Illinois from Colorado.
I’m not ready to book a flight from Colorado to Illinois right now. Can momondo alert me if prices change?
If you are not ready to book a flight from Colorado to Illinois now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Illinois and let you know when they change.