How many flights depart from Colorado to Illinois on average per day?

As of April 2026, 77 flights take off from Colorado and land in Illinois each day. The most common flight departure time for this route is 11:00AM, with 51% of daily flights taking off at noon.

How long is the flight from Colorado to Illinois?

The flight from Colorado to Illinois depends on which airports you’re departing and arriving from and whether or not you have a layover. If you fly from Denver (a popular airport in Colorado) to Chicago O'Hare Intl Airport (the most popular airport in Illinois), then the flight time is 2h 23m on average. If you fly from Colorado Springs (another popular airport in Colorado) to Chicago O'Hare Intl Airport, then the average flight time is 2h 34m.

What airlines fly to Illinois?

United Airlines, American Airlines and Frontier 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 37% 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.

What is the cheapest airline that flies from Colorado to Illinois?

Delta, Southwest, and Allegiant Air are the most popular carriers operating from Colorado to Illinois

How many flights depart from Colorado to Illinois on average per week?

The number of flights available between Colorado and Illinois is 543 per week as of April 2026. The most frequent departure day is Mon, with 17% of weekly flights leaving on this day.

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 April 2026, there are 6 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.

$53 Cheap Flights from Colorado to Illinois in 2026

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Find the cheapest flights from Colorado to Illinois

Round-trip

One-way

Last minute

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Cheap round-trip flights

Enter your travel dates to find the best prices.

2:17 pm - 5:24 pm

DEN

PIA

2h 07mnonstop

10:07 am - 11:26 am

PIA

DEN

2h 19mnonstop

$106Allegiant Air

jue., ago. 27 - dom., ago. 30

4:15 pm - 7:23 pm

DEN

STL

2h 08mnonstop

9:18 pm - 3:25 am

STL

DEN

7h 07m

1 stop

$113Frontier

sáb., may. 9 - lun., may. 11

6:35 am - 9:55 am

DEN

MDW

2h 20mnonstop

8:30 pm - 10:15 pm

MDW

DEN

2h 45mnonstop

$189Southwest

mié., jun. 3 - sáb., jun. 6

5:05 am - 2:05 pm

DEN

ORD

8h 00m

2 stops

9:37 pm - 11:44 pm

ORD

DEN

3h 07mnonstop

$191Multiple Airlines

mié., may. 20 - mié., may. 27

11:40 am - 5:15 pm

DEN

MDW

4h 35m

1 stop

8:50 pm - 10:35 pm

MDW

DEN

2h 45mnonstop

$196Southwest

sáb., may. 23 - mié., may. 27

5:13 pm - 10:59 pm

COS

STL

4h 46m

1 stop

6:11 pm - 11:32 pm

STL

COS

6h 21m

1 stop

$241American Airlines

jue., may. 7 - sáb., may. 9

3:45 pm - 11:59 pm

COS

STL

7h 14m

1 stop

5:25 am - 9:54 am

STL

COS

5h 29m

1 stop

$250American Airlines

mié., jun. 3 - mié., jun. 10

4:27 pm - 7:30 pm

DEN

PIA

2h 03mnonstop

4:23 pm - 11:01 pm

PIA

DEN

31h 38m

2 stops

$261Multiple Airlines

dom., may. 24 - dom., may. 31

5:38 pm - 8:54 pm

DEN

MLI

2h 16mnonstop

9:05 am - 10:35 am

MLI

DEN

2h 30mnonstop

$269United Airlines

mar., jun. 9 - dom., jun. 28

6:00 am - 12:39 pm

DEN

MLI

5h 39m

1 stop

9:05 am - 10:35 am

MLI

DEN

2h 30mnonstop

$279United Airlines

mar., jun. 9 - dom., jun. 28

American Airlines flights from Colorado to Illinois

Our best American Airlines deals on Colorado to Illinois flight tickets

American Airlines

May 20

DEN7:36 amDenver Intl

2h 36m

ORD11:12 amChicago O'Hare Intl

May 25

ORD9:52 amChicago O'Hare Intl

2h 44m

DEN11:36 amDenver Intl

$233

American Airlines

May 7

COS5:13 pmColorado Springs

4h 46m

1 stop

STL10:59 pmLambert-St Louis

May 9

STL6:11 pmLambert-St Louis

6h 21m

1 stop

COS11:32 pmColorado Springs

$241

American Airlines

Jun 3

COS3:45 pmColorado Springs

7h 14m

1 stop

STL11:59 pmLambert-St Louis

Jun 10

STL5:25 amLambert-St Louis

5h 29m

1 stop

COS9:54 amColorado Springs

$250

United Airlines flights from Colorado to Illinois

Our best United Airlines deals on Colorado to Illinois flight tickets

United Airlines

Jun 9

DEN5:38 pmDenver Intl

2h 16m

MLI8:54 pmMoline Quad-City

Jun 28

MLI9:05 amMoline Quad-City

2h 30m

DEN10:35 amDenver Intl

$269

United Airlines

Jun 9

DEN6:00 amDenver Intl

5h 39m

1 stop

MLI12:39 pmMoline Quad-City

Jun 28

MLI9:05 amMoline Quad-City

2h 30m

DEN10:35 amDenver Intl

$279

United Airlines

May 16

COS1:25 pmColorado Springs

4h 39m

1 stop

ORD7:04 pmChicago O'Hare Intl

May 19

ORD8:46 amChicago O'Hare Intl

3h 01m

COS10:47 amColorado Springs

$281

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Quickest round-trip

DenverPeoria

DEN - PIA

DENPIA

Denver Intl

jue. 8/27

2:17 pm-5:24 pm

Nonstop2h 07m

Greater Peoria

dom. 8/30

10:07 am-11:26 am

Nonstop2h 19m

$106

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

sáb. 5/9

4:15 pm-7:23 pm

Nonstop2h 08m

Lambert-St Louis

lun. 5/11

9:18 pm-3:25 am

1 stop7h 07m

$113

DenverChicago

DEN - MDW

DENMDW

Denver Intl

mié. 6/3

6:35 am-9:55 am

Nonstop2h 20m

Chicago Midway

sáb. 6/6

8:30 pm-10:15 pm

Nonstop2h 45m

$189

DenverChicago

DEN - ORD

DENORD

Denver Intl

mié. 5/20

5:05 am-2:05 pm

2 stops8h 00m

Chicago O'Hare Intl

mié. 5/27

9:37 pm-11:44 pm

Nonstop3h 07m

$191

DenverChicago

DEN - MDW

DENMDW

Denver Intl

sáb. 5/23

11:40 am-5:15 pm

1 stop4h 35m

Chicago Midway

mié. 5/27

8:50 pm-10:35 pm

Nonstop2h 45m

$196

Colorado SpringsSt. Louis

COS - STL

COSSTL

Colorado Springs

jue. 5/7

5:13 pm-10:59 pm

1 stop4h 46m

Lambert-St Louis

sáb. 5/9

6:11 pm-11:32 pm

1 stop6h 21m

$241

Colorado SpringsSt. Louis

COS - STL

COSSTL

Colorado Springs

mié. 6/3

3:45 pm-11:59 pm

1 stop7h 14m

Lambert-St Louis

mié. 6/10

5:25 am-9:54 am

1 stop5h 29m

$250

DenverPeoria

DEN - PIA

DENPIA

Denver Intl

dom. 5/24

4:27 pm-7:30 pm

Nonstop2h 03m

Greater Peoria

dom. 5/31

4:23 pm-11:01 pm

2 stops31h 38m

$261

DenverMoline

DEN - MLI

DENMLI

Denver Intl

mar. 6/9

5:38 pm-8:54 pm

Nonstop2h 16m

Moline Quad-City

dom. 6/28

9:05 am-10:35 am

Nonstop2h 30m

$269

DenverMoline

DEN - MLI

DENMLI

Denver Intl

mar. 6/9

6:00 am-12:39 pm

1 stop5h 39m

Moline Quad-City

dom. 6/28

9:05 am-10:35 am

Nonstop2h 30m

$279

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

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

Prices

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Other information

What is the cheapest month to fly to Illinois?

The cheapest month to fly to Illinois from Colorado is in August. Flight prices, which tend to average around $195, 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 August, then flying in January is also cheap. Prices for this month can be found on momondo for an average of $198.

What is the cheapest day to depart on your flight to Illinois?

The cheapest day to depart from Colorado to Illinois is on a Thursday when prices can be found for as low as $296. Flights from Colorado to Illinois on a Sunday will generally be more expensive and average around $508. 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 $221. Flights at noon are often more expensive with an average ticket price of $536.

What is the cheapest Colorado to Illinois flight route?

Fly from Denver Intl to Greater Peoria 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 weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $263 when searching 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 $204 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.

Can stopping save me money on Colorado to Illinois flights?

No. A direct flight is the cheapest option for a flight between Colorado to Illinois.

Cheap Colorado to Illinois flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Colorado to Illinois

Best Price Found	$74
Fastest flight time	2h 00m
Direct flights	Every day
Airports in Illinois	98 airports

The best one-way flight to Illinois from Colorado in the past 72 hours is $74. The best round-trip flight deal from Colorado to Illinois found on momondo in the last 72 hours is $271.

The fastest flight from Colorado to Illinois takes 2h 00m

Direct flights go from Colorado to Illinois every day.

There are 98 airports in Illinois. From Colorado there are direct flights to Greater Peoria (PIA), Lambert-St Louis (STL), Moline Quad-City (MLI).

Search flight deals

Frequently asked questions about flying 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 April 2026, there are 6 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 (15.83% of total bookings). The next most popular plane models are Boeing 737-800 (13.55%), Airbus A319 (10.06%), and Boeing 737 MAX 8 (10.04%).

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
Allegiant Air	PriceFrom $54	Free Cancellation	Rating 7.3 706 reviews	Search Allegiant Air flights
Frontier	PriceFrom $74	Free Cancellation	Rating 5.6 2,982 reviews	Search Frontier flights
JetBlue	PriceFrom $126	Free Cancellation	Rating 7.2 2,948 reviews	Search JetBlue flights
Southwest	PriceFrom $157	Free Cancellation	Rating 8.0 4,331 reviews	Search Southwest flights
American Airlines	PriceFrom $159	Free Cancellation	Rating 7.1 11,646 reviews	Search American Airlines flights
United Airlines	PriceFrom $167	Free Cancellation	Rating 7.4 9,613 reviews	Search United Airlines flights

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.

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Flights to Las Vegasfrom $37

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Flights to Bostonfrom $75

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Flights to Dallasfrom $60

Flights to Fort Lauderdalefrom $56

Cheap flights from Colorado to Illinois from $53

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 5/17. 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

What is the cheapest month to fly to Illinois?

What is the cheapest day to depart on your flight to Illinois?

What is the cheapest time of day to depart on your flight to Illinois?

What is the cheapest Colorado to Illinois flight route?

How far in advance should I book a flight to Illinois?

What cabin class options are available on Colorado to Illinois flights?

Can stopping save me money on Colorado to Illinois flights?

What is the cheapest airline that flies from Colorado to Illinois?

What airlines fly to Illinois?

How many flights depart from Colorado to Illinois on average per day?

How many flights depart from Colorado to Illinois on average per week?

How long is the flight from Colorado to Illinois?

Cheap Colorado to Illinois flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Colorado to Illinois

Best Price Found

Fastest flight time

Direct flights

Airports in Illinois

Frequently asked questions about flying from Colorado to Illinois

Best airlines flying from Colorado to Illinois

Compare and see reviews for airlines that fly from Colorado to Illinois with momondo

Why use momondo?

An easier way to manage your Illinois trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to Illinois

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