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$43+ Cheap flights from Illinois to Colorado

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/29. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — DEN
Nov 26 — Dec 31
Tue 11/26
Tue 12/3
1 adult, Economy
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Cheap flight deals from Illinois to Colorado

Discover tips and strategies to find the most affordable flight options for your journey from Illinois (USIL) to Colorado (USCO). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated November 21, 2024.

Find flight deals from Illinois to Colorado

Cheapest flights from Illinois to Colorado
Explore the most affordable flight options available from Illinois to Colorado. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 21, 2024.

This Frontier deal was found by Cheapflights users on 11/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/127:15 amMDW - DEN
Nonstop2h 50mFrontier
Sun 12/158:55 pmDEN - MDW
Nonstop2h 18mFrontier
Deal found 11/21$78
This Kiwi.com deal was found by Cheapflights users on 11/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/246:55 amORD - DEN
Nonstop2h 57mFrontier
Thu 1/24:01 pmDEN - ORD
Nonstop2h 33mFrontier
Deal found 11/20$80
This Cheapflightsfares deal was found by Cheapflights users on 11/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/911:31 amSTL - DEN
1 stop10h 51mFrontier
Wed 12/115:05 amDEN - STL
Nonstop2h 08mFrontier
Deal found 11/19$82
This American Airlines deal was found by Cheapflights users on 11/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/128:45 pmORD - DEN
Nonstop2h 52mAmerican Airlines
Sat 12/147:00 amDEN - ORD
Nonstop2h 45mAmerican Airlines
Deal found 11/21$159
This Southwest deal was found by Cheapflights users on 11/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/248:35 pmMDW - DEN
Nonstop2h 45mSouthwest
Mon 12/308:55 pmDEN - MDW
Nonstop2h 20mSouthwest
Deal found 11/19$170
This CheapOair deal was found by Cheapflights users on 11/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/127:25 amORD - DEN
Nonstop3h 01mMultiple Airlines
Sat 12/1412:50 pmDEN - ORD
1 stop21h 45mMultiple Airlines
Deal found 11/20$172
This United Airlines deal was found by Cheapflights users on 11/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/112:30 pmORD - DEN
Nonstop2h 50mUnited Airlines
Sun 12/226:00 pmDEN - ORD
Nonstop2h 30mUnited Airlines
Deal found 11/20$192
This Southwest deal was found by Cheapflights users on 11/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/117:30 amORD - DEN
1 stop7h 05mSouthwest
Sat 12/146:20 amDEN - ORD
Nonstop2h 40mSouthwest
Deal found 11/20$204
This Sun Country Air deal was found by Cheapflights users on 11/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/2410:00 amORD - DEN
1 stop8h 17mSun Country Air
Mon 12/306:50 pmDEN - ORD
1 stop21h 48mSun Country Air
Deal found 11/21$205
This Delta deal was found by Cheapflights users on 11/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/1412:30 pmORD - DEN
1 stop4h 38mDelta
Tue 12/172:23 pmDEN - ORD
1 stop4h 22mDelta
Deal found 11/20$216
This Delta deal was found by Cheapflights users on 11/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/119:38 amMDW - DEN
1 stop4h 39mDelta
Thu 12/1210:50 amDEN - MDW
1 stop6h 42mDelta
Deal found 11/20$216
This Delta deal was found by Cheapflights users on 11/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/112:25 pmSTL - DEN
1 stop5h 25mDelta
Wed 12/186:29 pmDEN - STL
1 stop5h 36mDelta
Deal found 11/20$216

Find flights from Illinois to Colorado within your budget

Customize your flight search to find flights from Illinois to Colorado that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,612,795 searches. Data last updated November 21, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

ChicagoDenver

MDW - DEN

MDWDEN

Chicago Midway

Tue 1/21

8:15 am-10:08 am

Nonstop2h 53m

Denver Intl

Thu 1/23

8:55 pm-12:17 am

Nonstop2h 22m

$75

ChicagoDenver

ORD - DEN

ORDDEN

Chicago O'Hare Intl

Thu 1/30

7:25 am-9:15 am

Nonstop2h 50m

Denver Intl

Sun 2/2

8:59 pm-12:32 am

Nonstop2h 33m

$76

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Wed 12/11

6:46 pm-8:22 pm

Nonstop2h 36m

Denver Intl

Mon 12/16

5:05 am-8:13 am

Nonstop2h 08m

$77

ChicagoVail

ORD - EGE

ORDEGE

Chicago O'Hare Intl

Thu 1/23

7:25 am-2:38 pm

1 stop8h 13m

Vail Eagle County

Sun 1/26

3:28 pm-2:11 pm

1 stop21h 43m

$156

ChicagoDenver

ORD - DEN

ORDDEN

Chicago O'Hare Intl

Thu 12/12

8:45 pm-10:37 pm

Nonstop2h 52m

Denver Intl

Sat 12/14

7:00 am-10:45 am

Nonstop2h 45m

$159

ChicagoDenver

ORD - DEN

ORDDEN

Chicago O'Hare Intl

Thu 1/9

7:10 am-9:00 am

Nonstop2h 50m

Denver Intl

Sat 1/11

8:29 pm-11:59 pm

Nonstop2h 30m

$163

ChicagoDenver

MDW - DEN

MDWDEN

Chicago Midway

Sat 12/14

6:30 am-8:15 am

Nonstop2h 45m

Denver Intl

Wed 12/18

6:55 am-10:25 am

Nonstop2h 30m

$170

ChicagoDenver

ORD - DEN

ORDDEN

Chicago O'Hare Intl

Thu 12/12

7:25 am-9:26 am

Nonstop3h 01m

Denver Intl

Sat 12/14

12:50 pm-11:35 am

1 stop21h 45m

$172

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Tue 1/28

8:27 am-10:05 am

Nonstop2h 38m

Denver Intl

Thu 1/30

9:40 am-12:48 pm

Nonstop2h 08m

$177

St. LouisDenver

STL - DEN

STLDEN

Lambert-St Louis

Thu 1/9

7:20 am-8:55 am

Nonstop2h 35m

Denver Intl

Mon 1/13

7:20 pm-10:20 pm

Nonstop2h 00m

$198

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/21

Showing 1-10 of 60 results
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Best time to book a flight from Illinois to Colorado

Have a flexible travel schedule? Discover the best time to fly to Colorado from Illinois with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Travel insights for flights from Illinois to Colorado

Get recent, data-driven insights about flights from Illinois to Colorado including ideal travel times, pricing trends, and more.

What is the cheapest month to book a flight from Illinois to Colorado?

Currently, October is the cheapest month in which you can book a flight from Illinois to Colorado (average of $197). Flying from Illinois to Colorado in March is currently the most expensive (average of $271). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from IL to CO?

Find hourly flight availability from Illinois to Colorado. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 21, 2024.

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

Weekly flight availability from Illinois to Colorado

Explore weekly flight availability from Illinois to Colorado. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated November 21, 2024.

The most flights from USIL to USCO are scheduled on a Wednesday (50 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (23 on average).

Rainfall in Colorado by month

Plan your trip to Colorado by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Colorado ranges from 0.5 - 2.3 inches per month. May is typically the wettest month, when rainfall can reach 2.3 in. January is typically the driest time to visit Colorado when rainfall is around 0.5 in.

Temperature in Colorado by month

Plan your trip to Colorado by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Colorado, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 30.2 F).

Reviews of airlines servicing Colorado

Get insights into the airlines that provide service to Colorado. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Colorado. Reviews last updated November 21, 2024.
Peruse reviews from past customers who have flown with Frontier, American Airlines and Southwest from Illinois to Colorado to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
5,005 reviews

Boarding

8.2

Food

7.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Reviews

1 / 10

My first time, surprisingly good! It was a good ride overall. Coming from Singapore, this budget flight is better than the budget airline for our national carrier Singapore Airlines.

Southwest
8.1
Very good
5,005 reviews
Southwest
8.1
Very good
5,005 reviews

Boarding

8.2

Food

7.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Reviews

1 / 10

My first time, surprisingly good! It was a good ride overall. Coming from Singapore, this budget flight is better than the budget airline for our national carrier Singapore Airlines.

Alaska Airlines
8.0
Very good
9,464 reviews
Southwest
8.1
Very good
5,005 reviews

Boarding

8.2

Food

7.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Reviews

1 / 10

My first time, surprisingly good! It was a good ride overall. Coming from Singapore, this budget flight is better than the budget airline for our national carrier Singapore Airlines.

Delta
8.0
Very good
8,755 reviews
Southwest
8.1
Very good
5,005 reviews

Boarding

8.2

Food

7.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Reviews

1 / 10

My first time, surprisingly good! It was a good ride overall. Coming from Singapore, this budget flight is better than the budget airline for our national carrier Singapore Airlines.

United Airlines
7.4
Good
9,172 reviews
Southwest
8.1
Very good
5,005 reviews

Boarding

8.2

Food

7.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Reviews

1 / 10

My first time, surprisingly good! It was a good ride overall. Coming from Singapore, this budget flight is better than the budget airline for our national carrier Singapore Airlines.

Allegiant Air
7.4
Good
850 reviews
Southwest
8.1
Very good
5,005 reviews

Boarding

8.2

Food

7.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Reviews

1 / 10

My first time, surprisingly good! It was a good ride overall. Coming from Singapore, this budget flight is better than the budget airline for our national carrier Singapore Airlines.

Related info for your journey

Find useful and relevant information for your journey from Illinois to Colorado. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

    One-way options have recently been found by users for as low as $43 on Frontier. Other airlines that offer cheap prices include American Airlines from $70 and United Airlines from $79 one-way.

  • Can I find deals for flights from Illinois to Colorado that include hotel bookings?

    Yes. In addition to deals on Illinois to Colorado flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Illinois to Colorado?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Illinois to Colorado.

  • Can I find deals for business class flights from Illinois to Colorado?

    Yes. Cheapflights offers flight deals from Illinois to Colorado by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Illinois to Colorado?

    Currently, October is the cheapest month in which you can book a flight from Illinois to Colorado (average of $197). Flying from Illinois to Colorado in March is currently the most expensive (average of $271). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for Illinois to Colorado

See prices for flight routes from nearby airports that may be better suited for you.
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Top 6 airlines flying from Illinois to Colorado

Discover the top 6 airlines that operate flights from Illinois to Colorado. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,612,795 searches. Data last updated November 21, 2024.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$39Average$149FlexibilityNo cancel feeOn-time62%
Allegiant AirCheapest$93Average$177FlexibilityNo cancel feeOn-time88%
American AirlinesCheapest$139Average$425FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$153Average$498FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$156Average$311FlexibilityNo cancel feeOn-time63%
DeltaCheapest$185Average$459FlexibilityNo cancel feeOn-timeN/A
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