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

The number of flights available between Denver and Illinois is 73 per day as of September 2026. The most frequent departure time is 9:00AM, with 47% of daily flights leaving in the afternoon.

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

As of September 2026, 512 flights take off from Denver and land in Illinois each week. The most common flight departure day for this route is Thu, with 19% of weekly flights taking off on this day.

What is the cheapest airline that flies from Denver Intl to Illinois?

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

What airlines fly to Illinois?

United Airlines, American Airlines and Frontier are the top three most popular airlines that fly to Illinois from Denver according to our data. United Airlines is the first choice among our users, with 44% 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.

When did momondo last update prices for flights from Denver Intl Airport to Illinois?

Prices for flights from Denver Intl Airport to Illinois are updated daily.

How many operators does momondo search for flights from Denver Intl Airport to Illinois?

The number of operators available for flights from Denver Intl Airport to Illinois is 6 as of September 2026.

How old do you have to be to fly from Denver Intl Airport to Illinois?

The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Denver Intl Airport to Illinois.

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

The travel and health documents you'll need for your trip to Illinois 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 Illinois. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

$34 Cheap Flights from Denver to Illinois in 2026

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from Denver 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.

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

1h 59mnonstop

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

2h 20mnonstop

$115Allegiant Air

Thu, Oct 29 - Sun, Nov 1

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

1h 59mnonstop

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

2h 20mnonstop

$126Allegiant Air

Thu, Oct 29 - Sun, Nov 1

6:30 am - 4:58 pmDEN Denver Intl-STL Lambert-St Louis

9h 28m1 stop Dallas/Fort Worth

8:00 pm - 9:39 pmSTL Lambert-St Louis-DEN Denver Intl

2h 39mnonstop

$136Frontier

Thu, Oct 15 - Mon, Oct 19

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

2h 05mnonstop

12:27 pm - 3:00 pmSTL Lambert-St Louis-DEN Denver Intl

27h 33m1 stop Las Vegas Harry Reid Intl

$136Frontier

Wed, Sep 23 - Thu, Sep 24

9:10 pm - 5:14 pmDEN Denver Intl-ORD Chicago O'Hare Intl

19h 04m1 stop Minneapolis St Paul

6:30 am - 8:26 amORD Chicago O'Hare Intl-DEN Denver Intl

2h 56mnonstop

$168Multiple Airlines

Sat, Oct 24 - Wed, Oct 28

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

2h 06mnonstop

5:10 am - 6:43 amSTL Lambert-St Louis-DEN Denver Intl

2h 33mnonstop

$177United Airlines

Sat, Oct 10 - Tue, Oct 13

5:52 pm - 8:59 pmDEN Denver Intl-STL Lambert-St Louis

2h 07mnonstop

1:40 pm - 3:09 pmSTL Lambert-St Louis-DEN Denver Intl

2h 29mnonstop

$177United Airlines

Sat, Nov 7 - Wed, Nov 11

8:05 pm - 11:15 pmDEN Denver Intl-STL Lambert-St Louis

2h 10mnonstop

8:35 am - 9:50 amSTL Lambert-St Louis-DEN Denver Intl

2h 15mnonstop

$177Southwest

Mon, Sep 21 - Tue, Sep 22

6:35 am - 9:35 amDEN Denver Intl-STL Lambert-St Louis

2h 00mnonstop

8:50 pm - 10:15 pmSTL Lambert-St Louis-DEN Denver Intl

2h 25mnonstop

$177Southwest

Wed, Sep 30 - Wed, Oct 7

9:10 pm - 4:33 pmDEN Denver Intl-ORD Chicago O'Hare Intl

18h 23m1 stop Minneapolis St Paul

6:30 am - 8:19 amORD Chicago O'Hare Intl-DEN Denver Intl

2h 49mnonstop

$188Multiple Airlines

Sat, Oct 3 - Sat, Oct 10

Cheap last minute flights

Enter your travel dates to find the best prices.

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

2h 28mnonstop

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

2h 45mnonstop

$183Frontier

Wed, Sep 9 - Thu, Sep 10

9:55 am - 1:36 pmDEN Denver Intl-ORD Chicago O'Hare Intl

2h 41mnonstop

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

2h 45mnonstop

$188Frontier

Sun, Sep 6 - Wed, Sep 9

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

2h 03mnonstop

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

2h 20mnonstop

$199Allegiant Air

Thu, Sep 10 - Sun, Sep 13

6:00 am - 9:43 amDEN Denver Intl-ORD Chicago O'Hare Intl

2h 43mnonstop

5:51 pm - 7:45 pmORD Chicago O'Hare Intl-DEN Denver Intl

2h 54mnonstop

$351United Airlines

Wed, Sep 9 - Wed, Sep 9

6:30 am - 9:50 amDEN Denver Intl-MDW Chicago Midway

2h 20mnonstop

2:05 pm - 3:35 pmMDW Chicago Midway-DEN Denver Intl

2h 30mnonstop

$351Southwest

Wed, Sep 9 - Thu, Sep 10

2:00 pm - 5:25 pmDEN Denver Intl-MDW Chicago Midway

2h 25mnonstop

4:25 pm - 6:00 pmMDW Chicago Midway-DEN Denver Intl

2h 35mnonstop

$351Southwest

Thu, Sep 10 - Fri, Sep 11

3:13 pm - 10:08 pmDEN Denver Intl-BMI Bloomington-Normal

5h 55m1 stop Dallas/Fort Worth

1:19 pm - 4:57 pmBMI Bloomington-Normal-DEN Denver Intl

4h 38m1 stop Chicago O'Hare Intl

$365American Airlines

Wed, Sep 9 - Wed, Sep 16

1:17 pm - 12:03 amDEN Denver Intl-BMI Bloomington-Normal

9h 46m2 stops Dallas/Fort Worth Chicago O'Hare Intl

5:02 am - 8:37 amBMI Bloomington-Normal-DEN Denver Intl

4h 35m1 stop Chicago O'Hare Intl

$370American Airlines

Wed, Sep 9 - Wed, Sep 16

10:55 am - 4:57 pmDEN Denver Intl-MDW Chicago Midway

5h 02m1 stop Detroit Metropolitan Wayne County

9:59 am - 3:24 pmMDW Chicago Midway-DEN Denver Intl

6h 25m1 stop Minneapolis St Paul

$371Delta

Thu, Sep 10 - Sat, Sep 12

5:40 pm - 9:01 pmDEN Denver Intl-MLI Moline Quad-City

2h 21mnonstop

9:05 am - 10:34 amMLI Moline Quad-City-DEN Denver Intl

2h 29mnonstop

$409United Airlines

Thu, Sep 10 - Sat, Sep 12

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Frontier flights from Denver to Illinois

Our best Frontier deals on Denver to Illinois flight tickets

Frontier

Sep 23

DEN4:12 pmDenver Intl

2h 05m

STL7:17 pmLambert-St Louis

Sep 24

STL12:27 pmLambert-St Louis

27h 33m

1 stop

DEN3:00 pmDenver Intl

$136

Frontier

Oct 10

DEN3:54 pmDenver Intl

2h 03m

STL6:57 pmLambert-St Louis

Oct 12

STL1:30 pmLambert-St Louis

11h 13m

1 stop

DEN11:43 pmDenver Intl

$138

Frontier

Sep 25

DEN4:12 pmDenver Intl

2h 05m

STL7:17 pmLambert-St Louis

Sep 30

STL8:10 pmLambert-St Louis

2h 29m

DEN9:39 pmDenver Intl

$140

Southwest flights from Denver to Illinois

Our best Southwest deals on Denver to Illinois flight tickets

Southwest

Sep 29

DEN6:35 amDenver Intl

2h 00m

STL9:35 amLambert-St Louis

Oct 1

STL9:50 pmLambert-St Louis

2h 20m

DEN11:10 pmDenver Intl

$177

Southwest

Sep 26

DEN11:15 amDenver Intl

3h 20m

1 stop

STL3:35 pmLambert-St Louis

Oct 5

STL9:50 pmLambert-St Louis

2h 25m

DEN11:15 pmDenver Intl

$183

Southwest

Sep 29

DEN8:10 amDenver Intl

5h 15m

1 stop

STL2:25 pmLambert-St Louis

Oct 1

STL9:50 pmLambert-St Louis

2h 20m

DEN11:10 pmDenver Intl

$187

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Quickest round-trip

DenverPeoria

DEN Denver Intl - PIA Greater Peoria

DENPIA

Denver Intl

Thu 10/29

10:20 am-1:19 pm

Nonstop1h 59m

Greater Peoria

Sun 11/1

5:24 pm-6:44 pm

Nonstop2h 20m

$115

DenverPeoria

DEN Denver Intl - PIA Greater Peoria

DENPIA

Denver Intl

Thu 10/29

10:20 am-1:19 pm

Nonstop1h 59m

Greater Peoria

Sun 11/1

5:24 pm-6:44 pm

Nonstop2h 20m

$126

DenverSt. Louis

DEN Denver Intl - STL Lambert-St Louis

DENSTL

Denver Intl

Thu 10/15

6:30 am-4:58 pm

1 stop9h 28m

Lambert-St Louis

Mon 10/19

8:00 pm-9:39 pm

Nonstop2h 39m

$136

DenverSt. Louis

DEN Denver Intl - STL Lambert-St Louis

DENSTL

Denver Intl

Wed 9/23

4:12 pm-7:17 pm

Nonstop2h 05m

Lambert-St Louis

Thu 9/24

12:27 pm-3:00 pm

1 stop27h 33m

$136

DenverChicago

DEN Denver Intl - ORD Chicago O'Hare Intl

DENORD

Denver Intl

Sat 10/24

9:10 pm-5:14 pm

1 stop19h 04m

Chicago O'Hare Intl

Wed 10/28

6:30 am-8:26 am

Nonstop2h 56m

$168

DenverSt. Louis

DEN Denver Intl - STL Lambert-St Louis

DENSTL

Denver Intl

Sat 10/10

5:30 pm-8:36 pm

Nonstop2h 06m

Lambert-St Louis

Tue 10/13

5:10 am-6:43 am

Nonstop2h 33m

$177

DenverSt. Louis

DEN Denver Intl - STL Lambert-St Louis

DENSTL

Denver Intl

Sat 11/7

5:52 pm-8:59 pm

Nonstop2h 07m

Lambert-St Louis

Wed 11/11

1:40 pm-3:09 pm

Nonstop2h 29m

$177

DenverSt. Louis

DEN Denver Intl - STL Lambert-St Louis

DENSTL

Denver Intl

Mon 9/21

8:05 pm-11:15 pm

Nonstop2h 10m

Lambert-St Louis

Tue 9/22

8:35 am-9:50 am

Nonstop2h 15m

$177

DenverSt. Louis

DEN Denver Intl - STL Lambert-St Louis

DENSTL

Denver Intl

Wed 9/30

6:35 am-9:35 am

Nonstop2h 00m

Lambert-St Louis

Wed 10/7

8:50 pm-10:15 pm

Nonstop2h 25m

$177

DenverChicago

DEN Denver Intl - ORD Chicago O'Hare Intl

DENORD

Denver Intl

Sat 10/3

9:10 pm-4:33 pm

1 stop18h 23m

Chicago O'Hare Intl

Sat 10/10

6:30 am-8:19 am

Nonstop2h 49m

$188

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 Denver 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

Airlines

Other information

What is the cheapest month to fly to Illinois?

The cheapest month to fly to Illinois from Denver is in January. Flight prices, which tend to average around $237, 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 November is also cheap. Prices for this month can be found on momondo for an average of $249.

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

The cheapest day to depart from Denver to Illinois is on a Friday when prices can be found for as low as $328. Flights from Denver to Illinois on a Sunday will generally be more expensive and average around $547. 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 Denver to Illinois during this time can be as low as $259. Flights at noon are often more expensive with an average ticket price of $548.

What is the cheapest Denver Intl to Illinois flight route?

Fly from Denver Intl to Greater Peoria for the best Denver Intl - Illinois flight prices

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

You are more likely to see cheaper flights to Illinois from Denver when booking weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $298 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from Denver for as low as $236 on momondo.

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

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

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

Cheap Denver to Illinois flight deals and tips

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

Best Price Found	$34
Fastest flight time	1h 58m
Direct flights	Every day
Airports in Illinois	98 airports

The best one-way flight to Illinois from Denver in the past 72 hours is $34. The best round-trip flight deal from Denver to Illinois found on momondo in the last 72 hours is $115.

The fastest flight from Denver to Illinois takes 1h 58m

Direct flights go from Denver to Illinois every day.

There are 98 airports in Illinois. From Denver there are direct flights to Greater Peoria (PIA), Lambert-St Louis (STL).

Search flight deals

Frequently asked questions about flying from Denver to Illinois

When did momondo last update prices for flights from Denver Intl Airport to Illinois?
Prices for flights from Denver Intl Airport to Illinois are updated daily.
How many operators does momondo search for flights from Denver Intl Airport to Illinois?
The number of operators available for flights from Denver Intl Airport to Illinois is 6 as of September 2026.
How old do you have to be to fly from Denver Intl Airport to Illinois?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Denver Intl Airport to Illinois.
What documentation or ID do you need to fly to Illinois?
The travel and health documents you'll need for your trip to Illinois 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 Illinois. 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 Denver to Illinois?
momondo data reveals that the most frequently booked plane model on the route from Denver to Illinois is Airbus A321neo, representing 17.30% of all bookings. The subsequent popular models are Airbus A321-100/200 at 13.86%, Boeing 737-800 at 13.48%, and Boeing 737 MAX 8 at 9.20%.

Best airlines flying from Denver to Illinois

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

Airline	Rating	Free Cancellation	Price
Frontier	PriceFrom $81	Free Cancellation	Rating 5.6 2,624 reviews	Search Frontier flights
Allegiant Air	PriceFrom $91	Free Cancellation	Rating 7.3 676 reviews	Search Allegiant Air flights
JetBlue	PriceFrom $138	Free Cancellation	Rating 7.1 3,043 reviews	Search JetBlue flights
Southwest	PriceFrom $170	Free Cancellation	Rating 8.0 4,203 reviews	Search Southwest flights
American Airlines	PriceFrom $171	Free Cancellation	Rating 7.1 12,045 reviews	Search American Airlines flights
United Airlines	PriceFrom $182	Free Cancellation	Rating 7.4 10,169 reviews	Search United Airlines flights

Why use momondo?

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

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Denver to Illinois for you.

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

momondo does allow users to show only those flights to Illinois from Denver which offer a flexible booking policy as well as other useful filters and features.

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

Once all potential Denver to Illinois flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.

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

If you are not ready to book a flight from Denver 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.

An easier way to manage your Illinois trip

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Popular cities in Illinois

Flights to New Yorkfrom $56

Flights to Los Angelesfrom $45

Flights to Orlandofrom $43

Flights to Miamifrom $64

Flights to San Franciscofrom $38

Flights to Chicagofrom $59

Flights to Las Vegasfrom $50

Flights to Washington, D.C.from $53

Flights to Bostonfrom $91

Flights to Fort Lauderdalefrom $50

Flights to Atlantafrom $38

Flights to Dallasfrom $62

Cheap flights from Denver to Illinois from $34

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Denver to Illinois departing on 9/26. 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 Denver to Illinois

Our best Frontier deals on Denver to Illinois flight tickets

Southwest flights from Denver to Illinois

Our best Southwest deals on Denver to Illinois flight tickets

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See travel insights to Illinois from

How to get the cheapest flight ticket from Denver 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 Denver Intl to Illinois flight route?

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

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

Can stopping save me money on Denver to Illinois flights?

What is the cheapest airline that flies from Denver Intl to Illinois?

What airlines fly to Illinois?

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

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

Cheap Denver to Illinois flight deals and tips

Best Price Found

Fastest flight time

Direct flights

Airports in Illinois

Frequently asked questions about flying from Denver to Illinois

Best airlines flying from Denver to Illinois

Compare and see reviews for airlines that fly from Denver 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

Popular cities in Illinois

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

Denver flight routes

According to popular flight searches on momondo this year

Illinois flight routes

According to popular flight searches on momondo this year

Fly your favorite airline to Illinois

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