Illinois

$39+ Cheap flights from Colorado to Illinois

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 12/17. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — ORD
Nov 25 — Dec 21
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Cheap flight deals from Colorado to Illinois

Discover tips and strategies to find the most affordable flight options for your journey from Colorado (USCO) to Illinois (USIL). 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 20, 2024.

Find flight deals from Colorado to Illinois

Cheapest flights from Colorado to Illinois
Explore the most affordable flight options available from Colorado to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 20, 2024.

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 12/166:15 amDEN - ORD
1 stop29h 31mFrontier
Wed 12/186:00 amORD - DEN
Nonstop2h 57mFrontier
Deal found 11/19$81
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.
Wed 12/256:10 pmDEN - MDW
Nonstop2h 22mFrontier
Thu 1/307:15 amMDW - DEN
Nonstop2h 54mFrontier
Deal found 11/19$81
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.
Sat 12/145:05 amDEN - STL
Nonstop2h 08mFrontier
Mon 12/168:34 pmSTL - DEN
1 stop8h 20mFrontier
Deal found 11/19$82
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/118:50 pmDEN - ORD
Nonstop2h 32mUnited Airlines
Wed 12/187:10 amORD - DEN
Nonstop2h 50mUnited Airlines
Deal found 11/19$169
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.
Sat 12/146:20 amDEN - ORD
Nonstop2h 40mSouthwest
Wed 12/187:00 amORD - DEN
Nonstop2h 45mSouthwest
Deal found 11/19$170
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/2412:33 pmDEN - ORD
Nonstop2h 32mAmerican Airlines
Wed 1/88:42 amORD - DEN
Nonstop2h 52mAmerican Airlines
Deal found 11/19$172
This eDestinos 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/38:55 pmDEN - ORD
1 stop19h 45mMultiple Airlines
Tue 12/107:33 amORD - DEN
1 stop24h 53mMultiple Airlines
Deal found 11/19$179
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.
Sat 12/146:05 amDEN - MDW
Nonstop2h 30mSouthwest
Wed 12/188:20 amMDW - DEN
Nonstop2h 45mSouthwest
Deal found 11/19$179
This Sun Country Air 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 Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/1912:18 pmDEN - ORD
1 stop6h 27mSun Country Air
Tue 12/2410:00 amORD - DEN
1 stop8h 17mSun Country Air
Deal found 11/20$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.
Wed 12/1112:50 amDEN - ORD
1 stop5h 56mDelta
Mon 12/163:35 pmORD - DEN
1 stop5h 25mDelta
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 12/1112:50 amDEN - MDW
1 stop7h 08mDelta
Mon 12/169:38 amMDW - DEN
1 stop4h 39mDelta
Deal found 11/20$216
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/195:00 amDEN - STL
1 stop4h 50mAmerican Airlines
Tue 12/245:45 amSTL - DEN
1 stop5h 51mAmerican Airlines
Deal found 11/19$226

Find flights from Colorado to Illinois within your budget

Customize your flight search to find flights from Colorado to Illinois 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 2,629,791 searches. Data last updated November 20, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

DenverChicago

DEN - ORD

DENORD

Denver Intl

Fri 1/10

8:59 pm-12:35 am

Nonstop2h 36m

Chicago O'Hare Intl

Sun 1/12

7:25 am-9:26 am

Nonstop3h 01m

$76

DenverChicago

DEN - MDW

DENMDW

Denver Intl

Fri 1/10

8:55 pm-12:13 am

Nonstop2h 18m

Chicago Midway

Sun 1/12

7:15 am-9:05 am

Nonstop2h 50m

$76

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Sat 12/7

5:05 am-8:13 am

Nonstop2h 08m

Lambert-St Louis

Mon 12/9

6:46 pm-8:22 pm

Nonstop2h 36m

$77

DenverChicago

DEN - ORD

DENORD

Denver Intl

Wed 12/11

8:50 pm-12:22 am

Nonstop2h 32m

Chicago O'Hare Intl

Wed 12/18

7:10 am-9:00 am

Nonstop2h 50m

$169

DenverChicago

DEN - ORD

DENORD

Denver Intl

Sat 12/14

6:20 am-10:00 am

Nonstop2h 40m

Chicago O'Hare Intl

Wed 12/18

7:00 am-8:45 am

Nonstop2h 45m

$170

DenverChicago

DEN - ORD

DENORD

Denver Intl

Tue 12/24

12:33 pm-4:05 pm

Nonstop2h 32m

Chicago O'Hare Intl

Wed 1/8

8:42 am-10:34 am

Nonstop2h 52m

$172

DenverChicago

DEN - ORD

DENORD

Denver Intl

Tue 12/3

8:55 pm-5:40 pm

1 stop19h 45m

Chicago O'Hare Intl

Tue 12/10

7:33 am-7:26 am

1 stop24h 53m

$179

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Fri 2/14

7:47 am-2:36 pm

1 stop5h 49m

Lambert-St Louis

Tue 2/18

4:39 pm-6:15 pm

Nonstop2h 36m

$187

DenverChicago

DEN - MDW

DENMDW

Denver Intl

Sat 12/21

9:20 pm-12:35 am

Nonstop2h 15m

Chicago Midway

Tue 12/24

8:35 pm-10:20 pm

Nonstop2h 45m

$198

DenverChicago

DEN - ORD

DENORD

Denver Intl

Wed 12/11

12:50 am-7:46 am

1 stop5h 56m

Chicago O'Hare Intl

Mon 12/16

5:20 pm-9:52 pm

1 stop5h 32m

$216

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/19

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

Have a flexible travel schedule? Discover the best time to fly to Illinois from Colorado 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 Colorado to Illinois

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

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

Currently, September is the cheapest month in which you can book a flight from Colorado to Illinois (average of $232). Flying from Colorado to Illinois in June is currently the most expensive (average of $308). 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 CO to IL?

Find hourly flight availability from Colorado to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 20, 2024.

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

Weekly flight availability from Colorado to Illinois

Explore weekly flight availability from Colorado to Illinois. 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 20, 2024.

The most flights from USCO to USIL are scheduled on a Tuesday (47 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (27 on average).

Rainfall in Illinois by month

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

In terms of precipitation, rainfall in Illinois ranges from 1.7 - 4.9 inches per month. August is typically the wettest month, when rainfall can reach 4.9 in. January is typically the driest time to visit Illinois when rainfall is around 1.7 in.

Temperature in Illinois by month

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

If weather is an important factor for your trip to Illinois, 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 23.0 F).

Reviews of airlines servicing Illinois

Get insights into the airlines that provide service to Illinois. 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 Illinois. Reviews last updated November 20, 2024.
Read through reviews of airlines operating flights from Colorado to Illinois, such as Frontier, Southwest and American Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
8.1
Very good
5,014 reviews

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Comfort

8.1

Boarding

8.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

8.1
Very good
5,014 reviews
8.1
Very good
5,014 reviews

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Comfort

8.1

Boarding

8.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

8.0
Very good
9,461 reviews
8.1
Very good
5,014 reviews

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Comfort

8.1

Boarding

8.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

8.0
Very good
8,756 reviews
8.1
Very good
5,014 reviews

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Comfort

8.1

Boarding

8.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

7.4
Good
9,171 reviews
8.1
Very good
5,014 reviews

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Comfort

8.1

Boarding

8.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

7.2
Good
10,000 reviews
8.1
Very good
5,014 reviews

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Comfort

8.1

Boarding

8.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

Related info for your journey

Find useful and relevant information for your journey from Colorado to Illinois. 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 Colorado to Illinois one-way?

    The cheapest airline one-way is Frontier, with whom users have recently found tickets for as low as $39. However, be on the lookout for offers from United Airlines and Southwest, as they are both options that can get you from Colorado to Illinois for a low price.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Colorado to Illinois 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 Colorado to Illinois?

    Currently, September is the cheapest month in which you can book a flight from Colorado to Illinois (average of $232). Flying from Colorado to Illinois in June is currently the most expensive (average of $308). 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 Colorado to Illinois

See prices for flight routes from nearby airports that may be better suited for you.

Top 6 airlines flying from Colorado to Illinois

Discover the top 6 airlines that operate flights from Colorado to Illinois. 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 2,629,791 searches. Data last updated November 20, 2024.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$38Average$141FlexibilityNo cancel feeOn-time62%
Allegiant AirCheapest$84Average$165FlexibilityNo cancel feeOn-time88%
American AirlinesCheapest$139Average$464FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$140Average$318FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$144Average$442FlexibilityNo cancel feeOn-time69%
DeltaCheapest$189Average$472FlexibilityNo cancel feeOn-timeN/A
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