How long is the flight from Illinois to Colorado?

Flight times from Illinois to Colorado vary, but if you’re flying out of Peoria and flying into Denver (one of the most popular routes), then the duration is 2h 19m on average. Another popular route from Illinois to Colorado is flying from Moline to Denver, which will take roughly 2h 29m. Keep in mind that layovers or delays could extend your travel time.

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

As of August 2026, there are 565 flights per week flying from Illinois to Colorado. The most common day of the week flights depart is Fri, with 18% of flights taking off on this day.

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

As of August 2026, 80 flights take off from Illinois and land in Colorado each day. The most common flight departure time for this route is 7:00PM, with 33% of daily flights taking off in the afternoon.

What airlines fly to Colorado?

United Airlines, American Airlines and Frontier are the top three most popular airlines that fly to Colorado from Illinois according to our data. United Airlines is the first choice among our users, with 48% of people opting to fly with this airline when traveling to Colorado. Keep in mind that there are 7 different airlines that fly to Colorado on a routine basis, so you have a few additional options to choose from.

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

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

When did momondo last update prices for flights from Illinois to Colorado?

Prices for flights from Illinois to Colorado were last updated today.

How many operators does momondo search for flights from Illinois to Colorado?

There are 7 operators available for flights from Illinois to Colorado as of August 2026.

How old do you have to be to fly from Illinois to Colorado?

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Illinois to Colorado.

What documentation or ID do you need to fly to Colorado?

The travel and health documents you'll need for your trip to Colorado may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Colorado. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

$85 Cheap Flights from Illinois to Colorado in 2026

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from Illinois to Colorado

Round-trip

One-way

Last minute

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Cheap round-trip flights

Enter your travel dates to find the best prices.

12:17 pm - 6:33 pmSTL Lambert-St Louis-DEN Denver Intl

7h 16m1 stop Las Vegas Harry Reid Intl

4:12 pm - 7:17 pmDEN Denver Intl-STL Lambert-St Louis

2h 05mnonstop

$121Frontier

Sat, Sep 26 - Wed, Oct 7

8:10 pm - 9:39 pmSTL Lambert-St Louis-DEN Denver Intl

2h 29mnonstop

6:38 pm - 11:32 amDEN Denver Intl-STL Lambert-St Louis

15h 54m1 stop Las Vegas Harry Reid Intl

$121Frontier

Mon, Sep 28 - Tue, Sep 29

5:24 pm - 6:44 pmPIA Greater Peoria-DEN Denver Intl

2h 20mnonstop

10:20 am - 1:19 pmDEN Denver Intl-PIA Greater Peoria

1h 59mnonstop

$159Allegiant Air

Sun, Oct 25 - Thu, Oct 29

5:24 pm - 6:44 pmPIA Greater Peoria-DEN Denver Intl

2h 20mnonstop

10:20 am - 1:19 pmDEN Denver Intl-PIA Greater Peoria

1h 59mnonstop

$165Allegiant Air

Sun, Oct 25 - Thu, Oct 29

6:30 am - 8:15 amORD Chicago O'Hare Intl-DEN Denver Intl

2h 45mnonstop

9:10 pm - 6:43 pmDEN Denver Intl-ORD Chicago O'Hare Intl

20h 33m1 stop Minneapolis St Paul

$166Multiple Airlines

Tue, Sep 29 - Wed, Sep 30

6:30 am - 8:15 amORD Chicago O'Hare Intl-DEN Denver Intl

2h 45mnonstop

9:10 pm - 4:44 pmDEN Denver Intl-ORD Chicago O'Hare Intl

18h 34m1 stop Minneapolis St Paul

$167Multiple Airlines

Sat, Oct 3 - Sat, Oct 10

4:49 pm - 6:20 pmSTL Lambert-St Louis-DEN Denver Intl

2h 31mnonstop

5:30 pm - 8:36 pmDEN Denver Intl-STL Lambert-St Louis

2h 06mnonstop

$177United Airlines

Sat, Sep 26 - Sat, Oct 10

4:30 pm - 5:50 pmSTL Lambert-St Louis-DEN Denver Intl

2h 20mnonstop

5:59 pm - 8:59 pmDEN Denver Intl-STL Lambert-St Louis

2h 00mnonstop

$177United Airlines

Thu, Feb 4 - Sat, Feb 6

9:50 pm - 11:10 pmSTL Lambert-St Louis-DEN Denver Intl

2h 20mnonstop

5:50 am - 8:50 amDEN Denver Intl-STL Lambert-St Louis

2h 00mnonstop

$177Southwest

Thu, Oct 1 - Mon, Oct 5

9:50 pm - 11:10 pmSTL Lambert-St Louis-DEN Denver Intl

2h 20mnonstop

5:50 am - 8:50 amDEN Denver Intl-STL Lambert-St Louis

2h 00mnonstop

$177Southwest

Thu, Oct 1 - Mon, Oct 5

Cheap last minute flights

Enter your travel dates to find the best prices.

6:45 pm - 9:41 pmSTL Lambert-St Louis-DEN Denver Intl

27h 56m1 stop Las Vegas Harry Reid Intl

4:12 pm - 7:17 pmDEN Denver Intl-STL Lambert-St Louis

2h 05mnonstop

$192Frontier

Wed, Sep 2 - Sat, Oct 3

2:41 pm - 4:45 pmORD Chicago O'Hare Intl-DEN Denver Intl

3h 04mnonstop

8:55 pm - 12:23 amDEN Denver Intl-ORD Chicago O'Hare Intl

2h 28mnonstop

$199Frontier

Tue, Sep 1 - Thu, Oct 1

10:07 am - 11:27 amPIA Greater Peoria-DEN Denver Intl

2h 20mnonstop

2:16 pm - 5:19 pmDEN Denver Intl-PIA Greater Peoria

2h 03mnonstop

$282Allegiant Air

Thu, Sep 3 - Thu, Sep 10

2:15 pm - 3:45 pmMDW Chicago Midway-DEN Denver Intl

2h 30mnonstop

5:50 am - 9:10 amDEN Denver Intl-MDW Chicago Midway

2h 20mnonstop

$335Southwest

Tue, Sep 1 - Thu, Oct 1

9:00 am - 12:55 pmMDW Chicago Midway-DEN Denver Intl

4h 55m1 stop Louisville Intl

5:50 am - 9:10 amDEN Denver Intl-MDW Chicago Midway

2h 20mnonstop

$341Southwest

Tue, Sep 1 - Thu, Oct 1

6:45 pm - 11:59 pmMLI Moline Quad-City-DEN Denver Intl

6h 14m1 stop Chicago O'Hare Intl

5:30 am - 11:38 amDEN Denver Intl-MLI Moline Quad-City

5h 08m1 stop Dallas/Fort Worth

$354American Airlines

Wed, Sep 2 - Wed, Sep 9

6:45 pm - 11:59 pmMLI Moline Quad-City-DEN Denver Intl

6h 14m1 stop Chicago O'Hare Intl

6:26 am - 4:27 pmDEN Denver Intl-MLI Moline Quad-City

9h 01m2 stops Dallas/Fort Worth Chicago O'Hare Intl

$359American Airlines

Wed, Sep 2 - Wed, Sep 9

10:48 am - 7:16 pmPIA Greater Peoria-DEN Denver Intl

57h 28m2 stops Orlando Sanford Intl Charlotte Douglas

2:16 pm - 5:19 pmDEN Denver Intl-PIA Greater Peoria

2h 03mnonstop

$382Multiple Airlines

Mon, Aug 31 - Thu, Sep 10

9:10 pm - 6:28 amORD Chicago O'Hare Intl-DEN Denver Intl

10h 18m1 stop Dallas/Fort Worth

5:05 am - 1:55 pmDEN Denver Intl-ORD Chicago O'Hare Intl

7h 50m2 stops Dallas/Fort Worth Kirksville Cannon Memorial

$423Multiple Airlines

Tue, Sep 1 - Sat, Sep 5

10:07 am - 11:27 amPIA Greater Peoria-DEN Denver Intl

2h 20mnonstop

10:36 am - 9:35 amDEN Denver Intl-PIA Greater Peoria

45h 59m2 stops Allentown-Bethlehem Orlando Sanford Intl

$572Allegiant Air

Thu, Sep 3 - Mon, Sep 7

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Frontier flights from Illinois to Colorado

Our best Frontier deals on Illinois to Colorado flight tickets

Frontier

Sep 17

STL5:19 pmLambert-St Louis

15h 18m

1 stop

DEN7:37 amDenver Intl

Sep 19

DEN4:12 pmDenver Intl

2h 05m

STL7:17 pmLambert-St Louis

$121

Frontier

Sep 21

STL5:19 pmLambert-St Louis

15h 33m

1 stop

DEN7:52 amDenver Intl

Sep 26

DEN4:12 pmDenver Intl

2h 05m

STL7:17 pmLambert-St Louis

$122

Frontier

Sep 16

STL8:10 pmLambert-St Louis

2h 29m

DEN9:39 pmDenver Intl

Sep 19

DEN4:12 pmDenver Intl

2h 05m

STL7:17 pmLambert-St Louis

$123

Allegiant Air flights from Illinois to Colorado

Our best Allegiant Air deals on Illinois to Colorado flight tickets

Allegiant Air

Sep 6

PIA10:07 amGreater Peoria

2h 20m

DEN11:27 amDenver Intl

Sep 10

DEN2:16 pmDenver Intl

2h 03m

PIA5:19 pmGreater Peoria

$156

Allegiant Air

Oct 25

PIA5:24 pmGreater Peoria

2h 20m

DEN6:44 pmDenver Intl

Oct 29

DEN10:20 amDenver Intl

1h 59m

PIA1:19 pmGreater Peoria

$159

Allegiant Air

Oct 25

PIA5:24 pmGreater Peoria

2h 20m

DEN6:44 pmDenver Intl

Oct 29

DEN10:20 amDenver Intl

1h 59m

PIA1:19 pmGreater Peoria

$165

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisDenver

STL Lambert-St Louis - DEN Denver Intl

STLDEN

Lambert-St Louis

Sat 9/26

12:17 pm-6:33 pm

1 stop7h 16m

Denver Intl

Wed 10/7

4:12 pm-7:17 pm

Nonstop2h 05m

$121

St. LouisDenver

STL Lambert-St Louis - DEN Denver Intl

STLDEN

Lambert-St Louis

Mon 9/28

8:10 pm-9:39 pm

Nonstop2h 29m

Denver Intl

Tue 9/29

6:38 pm-11:32 am

1 stop15h 54m

$121

Quickest round-trip

PeoriaDenver

PIA Greater Peoria - DEN Denver Intl

PIADEN

Greater Peoria

Sun 10/25

5:24 pm-6:44 pm

Nonstop2h 20m

Denver Intl

Thu 10/29

10:20 am-1:19 pm

Nonstop1h 59m

$159

PeoriaDenver

PIA Greater Peoria - DEN Denver Intl

PIADEN

Greater Peoria

Sun 10/25

5:24 pm-6:44 pm

Nonstop2h 20m

Denver Intl

Thu 10/29

10:20 am-1:19 pm

Nonstop1h 59m

$165

ChicagoDenver

ORD Chicago O'Hare Intl - DEN Denver Intl

ORDDEN

Chicago O'Hare Intl

Tue 9/29

6:30 am-8:15 am

Nonstop2h 45m

Denver Intl

Wed 9/30

9:10 pm-6:43 pm

1 stop20h 33m

$166

ChicagoDenver

ORD Chicago O'Hare Intl - DEN Denver Intl

ORDDEN

Chicago O'Hare Intl

Sat 10/3

6:30 am-8:15 am

Nonstop2h 45m

Denver Intl

Sat 10/10

9:10 pm-4:44 pm

1 stop18h 34m

$167

St. LouisDenver

STL Lambert-St Louis - DEN Denver Intl

STLDEN

Lambert-St Louis

Sat 9/26

4:49 pm-6:20 pm

Nonstop2h 31m

Denver Intl

Sat 10/10

5:30 pm-8:36 pm

Nonstop2h 06m

$177

St. LouisDenver

STL Lambert-St Louis - DEN Denver Intl

STLDEN

Lambert-St Louis

Thu 2/4

4:30 pm-5:50 pm

Nonstop2h 20m

Denver Intl

Sat 2/6

5:59 pm-8:59 pm

Nonstop2h 00m

$177

St. LouisDenver

STL Lambert-St Louis - DEN Denver Intl

STLDEN

Lambert-St Louis

Thu 10/1

9:50 pm-11:10 pm

Nonstop2h 20m

Denver Intl

Mon 10/5

5:50 am-8:50 am

Nonstop2h 00m

$177

St. LouisDenver

STL Lambert-St Louis - DEN Denver Intl

STLDEN

Lambert-St Louis

Thu 10/1

9:50 pm-11:10 pm

Nonstop2h 20m

Denver Intl

Mon 10/5

5:50 am-8:50 am

Nonstop2h 00m

$177

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 Illinois to Colorado

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

Airlines

Other information

What is the cheapest month to fly to Colorado?

The month of November is, on average, the cheapest month to fly to Colorado from Illinois, with most prices found around $247. The month of October is another great option to travel to Colorado, with average flight prices from Illinois averaging around $249.

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

The cheapest day to depart from Illinois to Colorado is on a Wednesday when prices can be found for as low as $271. On the other hand, Monday is the most expensive day to depart from Illinois because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $365.

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

The cheapest time of day to fly to Colorado is in the evening when flights can be purchased for as low as $246. In the afternoon is when there is more demand to fly to Colorado, so prices are often more expensive at around $332 per ticket.

What is the cheapest Illinois to Colorado flight route?

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

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

You are more likely to see cheaper flights to Colorado from Illinois when booking weeks ahead of your departure date. In general, you can expect to find flights to Colorado for around $260 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Colorado from Illinois for as low as $224 on momondo.

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

There are 4 cabin classes available to choose from on Illinois to Colorado 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 Illinois to Colorado flights?

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

Cheap Illinois to Colorado flight deals and tips

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

Best Price Found	$85
Fastest flight time	2h 15m
Direct flights	Every day
Airports in Colorado	87 airports

The best one-way flight to Colorado from Illinois in the past 72 hours is $85. The best round-trip flight deal from Illinois to Colorado found on momondo in the last 72 hours is $121.

The fastest flight from Illinois to Colorado takes 2h 15m

Direct flights go from Illinois to Colorado every day.

There are 87 airports in Colorado. From Illinois there are direct flights to Colorado Springs (COS), Denver Intl (DEN).

Search flight deals

Frequently asked questions about flying from Illinois to Colorado

When did momondo last update prices for flights from Illinois to Colorado?
Prices for flights from Illinois to Colorado were last updated today.
How many operators does momondo search for flights from Illinois to Colorado?
There are 7 operators available for flights from Illinois to Colorado as of August 2026.
How old do you have to be to fly from Illinois to Colorado?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Illinois to Colorado.
What documentation or ID do you need to fly to Colorado?
The travel and health documents you'll need for your trip to Colorado may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Colorado. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from Illinois to Colorado?
Based on momondo bookings for flights between Illinois and Colorado, the leading plane model is Airbus A321neo, making up 15.55% of the total bookings. Other popular models include Airbus A321-100/200 with 12.76%, Boeing 737-800 with 12.04%, and Airbus A319 with 9.41%.

Best airlines flying from Illinois to Colorado

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

Airline	Rating	Free Cancellation	Price
Frontier	PriceFrom $70	Free Cancellation	Rating 5.6 2,637 reviews	Search Frontier flights
Allegiant Air	PriceFrom $74	Free Cancellation	Rating 7.3 676 reviews	Search Allegiant Air flights
Delta	PriceFrom $105	Free Cancellation	Rating 7.8 8,541 reviews	Search Delta flights
JetBlue	PriceFrom $145	Free Cancellation	Rating 7.1 3,033 reviews	Search JetBlue flights
Southwest	PriceFrom $151	Free Cancellation	Rating 8.0 4,199 reviews	Search Southwest flights
American Airlines	PriceFrom $156	Free Cancellation	Rating 7.1 12,022 reviews	Search American Airlines flights
United Airlines	PriceFrom $171	Free Cancellation	Rating 7.4 10,139 reviews	Search United Airlines flights

Why use momondo?

Why should I use momondo to find a flight deal from Illinois to Colorado?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Illinois to Colorado. momondo saves you time and could save you money on your trip.

Can I find flights from Illinois to Colorado with flexible booking policies on momondo?

Yes. momondo enables you to select and highlight flights to Colorado from Illinois with this policy.

How can momondo help me find flights from Illinois to Colorado?

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Illinois to Colorado.

I’m not ready to book a flight from Illinois to Colorado right now. Can momondo alert me if prices change?

Yes momondo offers price alerts on flights to Colorado from Illinois. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

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Popular cities in Colorado

Flights to New Yorkfrom $70

Flights to Los Angelesfrom $44

Flights to Orlandofrom $58

Flights to Miamifrom $74

Flights to San Franciscofrom $38

Flights to Chicagofrom $50

Flights to Las Vegasfrom $45

Flights to Washington, D.C.from $57

Flights to Bostonfrom $80

Flights to Fort Lauderdalefrom $50

Flights to Atlantafrom $43

Flights to Dallasfrom $51

Cheap flights from Illinois to Colorado from $85

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Illinois to Colorado departing on 9/24. 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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Frontier flights from Illinois to Colorado

Our best Frontier deals on Illinois to Colorado flight tickets

Allegiant Air flights from Illinois to Colorado

Our best Allegiant Air deals on Illinois to Colorado flight tickets

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How to get the cheapest flight ticket from Illinois to Colorado

What is the cheapest month to fly to Colorado?

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

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

What is the cheapest Illinois to Colorado flight route?

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

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

Can stopping save me money on Illinois to Colorado flights?

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

What airlines fly to Colorado?

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

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

How long is the flight from Illinois to Colorado?

Cheap Illinois to Colorado flight deals and tips

Best Price Found

Fastest flight time

Direct flights

Airports in Colorado

Frequently asked questions about flying from Illinois to Colorado

Best airlines flying from Illinois to Colorado

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

Why use momondo?

An easier way to manage your Colorado 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 Colorado

Popular cities in Colorado

Popular flights according to clicks in the last 7 days on momondo

Illinois flight routes

According to popular flight searches on momondo this year

Colorado flight routes

According to popular flight searches on momondo this year

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