How does KAYAK find such low prices on flights from Illinois to Denver?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Illinois to Denver. Visit our flight page for the latest deals!>/a>

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to Denver?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Denver from Illinois is likely to change within 7 days, so travelers know whether to wait or book now. Visit our flight page for the latest deals!>/a>

What is the Hacker Fare option on flights from Illinois to Denver?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Denver with an airline and back to Illinois with another airline. Visit our flight page for the latest deals!>/a>

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Illinois to Denver?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Denver from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best. Visit our flight page for the latest deals!>/a>

$22 CHEAP FLIGHTS from Illinois to Denver

DEN

KAYAK searches hundreds of travel sites at once for deals on flights to Denver

...and more

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Filter your dealsChoose cabin class, free Wi-Fi and more.

Cheapest round-trip

$68

Overall average: $197

Frontier

Sat 2/28Sat 3/7

STL - DEN • Non-stop

Cheapest one-way

$22

Typical prices: $57-$186

Frontier

Sat 2/28

STL - DEN • Non-stop

Start a new search

KAYAK searches 100s of sites at once to find you the best travel deals.

We hope you love your trip to Denver!

Flight Deals

Cheap Flights from Illinois to Denver

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Last minute

Direct

Recent round-trip flight deals from Illinois to Denver

Sat, Feb 28 - Sat, Mar 7

2:51 pm - 4:18 pm

STL

DEN

2h 27mnonstop

6:35 am - 9:49 am

DEN

STL

2h 14mnonstop

$68Frontier

Wed, Feb 25 - Sat, Feb 28

4:51 pm - 6:25 pm

STL

DEN

2h 34mnonstop

10:48 am - 1:56 pm

DEN

STL

2h 08mnonstop

$72Frontier

Fri, Feb 20 - Tue, Feb 24

8:49 am - 10:35 am

MLI

DEN

2h 46mnonstop

5:37 pm - 8:54 pm

DEN

MLI

2h 17mnonstop

$209United Airlines

Wed, Mar 4 - Sat, Mar 7

9:00 am - 10:05 am

PIA

DEN

2h 05mnonstop

7:45 am - 1:45 pm

DEN

PIA

5h 00m

1 stop

$219United Airlines

Sun, May 31 - Sun, May 31

11:09 am - 12:32 pm

PIA

DEN

2h 23mnonstop

4:27 pm - 7:30 pm

DEN

PIA

2h 03mnonstop

$228Allegiant Air

Fri, Feb 13 - Fri, Feb 20

7:00 pm - 10:37 pm

PIA

DEN

4h 37m

1 stop

5:57 pm - 11:25 pm

DEN

PIA

4h 28m

1 stop

$249American Airlines

Tue, Jul 21 - Mon, Jul 27

5:00 pm - 11:45 pm

MLI

DEN

7h 45m

1 stop

12:59 am - 10:26 am

DEN

MLI

8h 27m

1 stop

$249Delta

Thu, Jun 11 - Sun, Jun 14

11:07 am - 12:34 pm

PIA

DEN

2h 27mnonstop

4:50 pm - 7:56 pm

DEN

PIA

2h 06mnonstop

$257Allegiant Air

Tue, Mar 24 - Tue, Mar 31

4:04 pm - 12:09 am

BMI

DEN

9h 05m

1 stop

5:45 am - 3:23 pm

DEN

BMI

8h 38m

1 stop

$339Delta

Wed, Feb 25 - Wed, Mar 4

3:45 pm - 8:05 pm

BMI

DEN

5h 20m

1 stop

8:00 am - 3:15 pm

DEN

BMI

6h 15m

1 stop

$373American Airlines

Useful Info

Low season	November
High season	July
Cheapest flight	$22

Most popular time to fly with an average 2% increase in price.

Flight from St. Louis to Denver

How does KAYAK find such low prices on flights from Illinois to Denver?
KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Illinois to Denver.
How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to Denver?
KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Denver from Illinois is likely to change within 7 days, so travelers know whether to wait or book now.
What is the Hacker Fare option on flights from Illinois to Denver?
Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Denver with an airline and back to Illinois with another airline.
What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Illinois to Denver?
Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Denver from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Westminster

Lakewood

Dillon

Broomfield

Englewood

Greenwood Village

Central City

Lone Tree

Wheat Ridge

Limon

Brighton

Fort Morgan

Evergreen

Erie

Everything you need to know for your flight to Denver

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Cabin class

Complete your trip

Direct Flights

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Information on the airport you'll fly into in Denver

Denver (DEN)

DEN

$22 Find Cheap Flights from Illinois to Denver

KAYAK searches hundreds of travel sites at once for deals on flights to Denver

Everything you should know

Cheap Flights from Illinois to Denver

Recent round-trip flight deals from Illinois to Denver

Recent one-way flight deals from Illinois to Denver

Recent last minute flight deals from Illinois to Denver

Recent direct flight deals from Illinois to Denver

Good to know

FAQs for booking flights from Illinois to Denver

How does KAYAK find such low prices on flights from Illinois to Denver?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Illinois to Denver.

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to Denver?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Denver from Illinois is likely to change within 7 days, so travelers know whether to wait or book now.

What is the Hacker Fare option on flights from Illinois to Denver?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Denver with an airline and back to Illinois with another airline.

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Illinois to Denver?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Denver from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Traveling to a place near Denver?

Everything you need to know for your flight to Denver

Information on the airport you'll fly into in Denver

Cabin class types available on flights to Illinois

Complete your trip to Denver with a hotel stay or car rental

Find direct flights for Denver

Flights to other popular destinations

Flights from domestic origins to Denver

Choose which airport to fly into in Denver

Find deals for your return flight