Cheap flights from Illinois (IL) to Denver (DEN)

Know your dates, get live prices in seconds:

From
To
Depart
Return
Any month
Compare vs. Cheapflights |
From
To
Depart
Depart
Time
Anytime
From
To
Depart
Depart
Time
Anytime
From
To
Depart
Depart
Time
Anytime
From
To
Depart
Depart
Time
Anytime
From
To
Depart
Depart
Time
Anytime
From
To
Depart
Depart
Time
Anytime

We work with more than 300 partners to bring you better travel deals

How to find the cheapest flight from
Illinois to Denver (DEN)

All the information you need to plan the best null to DEN flight in 2021: compare Illinois to Denver flight prices with the expected peak season, weather and rainfall in Denver.
What is the cheapest month to fly from Illinois to Denver?

August can be a great time to fly to Denver from Illinois with a flight ticket averaging about $142. Cheapflights users have found deals in the month of August for as cheap as $37. The most expensive prices can be found in the month of December.

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

When searching for a good deal, it’s best to be prepared for potential fluctuations in price. We recommend booking at least 20 days in advance, which can save you up to 7% on flights from Illinois to Denver compared to booking the week you need them. Waiting 20 days out may not be for everyone, so we have options available for flights within the next two weeks, with the lowest price starting at $126. For sooner than that we have options available in the next 3 days from $137.

When is the cheapest time to fly from Illinois to Denver (IL - DEN)?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Illinois to Denver as you normally would.

Cheap flights from Illinois to Denver in October, November 2021

The best prices found for Illinois to DEN flights for October, November
6 Nov - 16 Nov
$63pp
ORD
Chicago O'Hare Intl
Frontier
Non-Stop
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
ORD
Chicago O'Hare Intl
5 Nov - 11 Nov
$63pp
STL
Lambert-St Louis
Frontier
Non-Stop
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
STL
Lambert-St Louis
26 Oct - 30 Oct
$64pp
ORD
Chicago O'Hare Intl
Multiple Airlines
 
1 STOP
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
ORD
Chicago O'Hare Intl

Illinois to Denver 2021 flight deals

Cheap flights to Denver from Illinois found for this year
1 Dec - 8 Dec
$61pp
STL
Lambert-St Louis
Frontier
Non-Stop
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
STL
Lambert-St Louis
10 Dec - 14 Dec
$63pp
ORD
Chicago O'Hare Intl
Frontier
Non-Stop
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
ORD
Chicago O'Hare Intl
5 Nov - 11 Nov
$63pp
STL
Lambert-St Louis
Frontier
Non-Stop
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
STL
Lambert-St Louis

Non-stop flights to Denver from Illinois

Save time with Illinois to Denver direct flight deals
1 Dec - 8 Dec
$61pp
STL
Lambert-St Louis
Frontier
Non-Stop
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
STL
Lambert-St Louis
5 Nov - 11 Nov
$63pp
STL
Lambert-St Louis
Frontier
Non-Stop
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
STL
Lambert-St Louis
6 Nov - 13 Nov
$63pp
ORD
Chicago O'Hare Intl
Frontier
Non-Stop
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
ORD
Chicago O'Hare Intl

Last minute flights from Illinois to Denver

Late deals on round-trip flights to Denver from Illinois, departing today and this week
26 Oct - 6 Nov
$63pp
ORD
Chicago O'Hare Intl
Frontier
Non-Stop
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
ORD
Chicago O'Hare Intl
26 Oct - 30 Oct
$64pp
ORD
Chicago O'Hare Intl
Multiple Airlines
 
1 STOP
DEN
Denver Intl
DEN
Denver Intl
Frontier
Non-Stop
ORD
Chicago O'Hare Intl
31 Oct - 4 Nov
$68pp
PIA
Greater Peoria
Allegiant Air
Non-Stop
DEN
Denver Intl
DEN
Denver Intl
Allegiant Air
Non-Stop
PIA
Greater Peoria

One-way flights to Denver Intl from Illinois

The cheapest one-way flights from Illinois to Denver
6:13 pm - 7:55 pm
American Airlines
Nonstop
2h 42m
ORD - DEN
American Airlines
5:25 pm - 6:59 pm
Frontier
Nonstop
2h 34m
STL - DEN
Frontier
$54
JustFly
2:30 pm - 9:10 am
Spirit Airlines
1 Stop
19h 40m
ORD - DEN
Spirit Airlines
$55
Gotogate

Related info for your journey

Useful info, stats and facts about <span class="emphasized">Illinois</span> to <span class="emphasized">Denver</span> flights.

Flight FAQs

From Illinois to Denver

What airport do you fly into for flights to Denver from Illinois?

For a flight from Illinois to Denver, you will be flying into Denver Intl. Denver Intl (DEN) is just 18.5 mi from the center of the city.

Which airlines flying from Illinois to Denver Intl have flexible cancellations due to COVID-19?

Frontier, United Airlines, and Spirit Airlines are some of the carriers that may have flexible cancellation policies. You can use our site to filter for other airlines that may also have this kind of flexibility.

Can I find flights from Illinois to Denver for under $100 on Cheapflights?

Yes, there are multiple flights from Illinois to Denver for under $100. The cheapest flight booked recently is on Frontier for just $61, but on average you can expect to pay $69.

Are there nonstop flights from Illinois to Denver for under $100 on Cheapflights?

Cheapflights has at least 20 direct flights from Illinois to Denver under $100. A good price for a nonstop flight from Illinois to Denver is less than $70.

Are there last-minute flights available from Illinois to Denver for under $100?

There are currently 20+ open flights from Illinois to Denver within the next 7 days for less than $100.

What days are nonstop flights available from Illinois to Denver?

Nonstop flights are available for this route on the following days: Thursday, Friday, Saturday.

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

On average 28 flights depart from Illinois to Denver per day.
Early Morning (Midnight to 6am) - 32% of flight departures
Morning (6am - Noon) - 21% of flight departures
Afternoon (Noon - 6pm) - 46% of flight departures

How long is the flight from Illinois to Denver?

Airlines like Frontier, Spirit Airlines, and Allegiant Air fly from Illinois to Denver in about 2h 10m. The time it takes to get you to your destination can typically vary by up to 13h 21m. Airlines will cover a distance of 891 mi. This flight may include one or multiple stops.

What are the cheapest airlines to fly from Illinois to Denver one-way?

The cheapest airlines for a one-way flight from Illinois to Denver are Spirit Airlines ($31), Frontier ($34), and American Airlines ($49).

What are the most popular routes from Illinois to Denver?

While some choose either Chicago Midway - Denver Intl or Lambert-St Louis - Denver Intl, Chicago O'Hare Intl - Denver Intl is the most popular route from Illinois to Denver.

What are the cheapest flights from Illinois to Denver?

While on average a flight from Illinois to Denver is generally $467, our data shows the cheapest flight currently is $42. When looking at the most popular route, (Chicago O'Hare Intl - Denver Intl), you can expect to pay $64 for that flight.

What are the most reliable airlines from Illinois to Denver?

The top 3 most reliable airlines when flying from Illinois to Denver are Air Canada (87%), Japan Airlines (86%) and Frontier (84%).

What are the most popular airlines that fly from Illinois to Denver?

When booking a flight from Illinois to Denver, you may want to consider flying on Major Airline, American Airlines or Delta as they are the most popular for this route.

Related searches

Flights to Denver (DEN) from Illinois
Flights to Illinois Flights to Denver Flights from Denver

Rent a Car

Car Rentals in Denver Car Rentals in Colorado

COVID Restrictions

View COVID Travel Restrictions for Denver, CO

Do I need a COVID test to fly to Denver from Illinois?

Information is based on travel restrictions for travel to Denver Intl within the United States

Most visitors from Illinois need to provide a negative COVID-19 test result and/or quarantine to enter Denver Intl.

COVID-19 testing requirements
Visitors from Illinois must present a negative RT-PCR (NAAT) or Antigen (quick-test) test taken 72 hours before departing to Denver Intl.

Quarantine requirements
Visitors from Illinois are not required to quarantine after entering Denver Intl.

Do I need a test to fly back to Illinois from Denver?

Returning to Illinois from Denver Intl

COVID-19 testing requirements
Visitors from Denver Intl must present a negative RT-PCR (NAAT) or Antigen (quick-test) test taken 72 hours before departing to Illinois.

Quarantine requirements
Visitors from Denver Intl are not required to quarantine after entering Illinois.

Hide COVID Travel Restrictions for Denver, CO

Departure points for flights from Illinois to Denver

Select to see more specific information for flights to Denver from all departure points in Illinois.

Destination information for Denver

Things to know before you go - useful duration and weather info for your trip from Illinois to Denver.
Flight duration from Illinois to DEN
2h 23m
Average temperature for October in Denver
66.2 °F
Avg rainfall for October in Denver
0.9 ″

Airports servicing

Bloomington (BMI)
Champaign (CMI)
Decatur (DEC)
Moline (MLI)
Marion (MWA)

Airports servicing Denver

Top 6 airlines flying from Illinois to Denver Intl

The chart below displays the airlines Cheapflights users traveling from Illinois to Denver choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.
Airline Cheapest Average Flexibility On-time COVID-19 safety
Frontier
$39 $163 No cancel fee 62%
Spirit Airlines
$53 $155 No cancel fee 65%
United Airlines
$53 $322 No cancel fee 69%
American Airlines
$60 $370 No cancel fee 71%
Delta
$82 $322 No cancel fee N/A
Southwest
$231 $382 No cancel fee 63%
Home North America USA Colorado Denver Cheap flights from Illinois to Denver