$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 4/2. Fares are subject to change and may not be available on all flights or dates of travel.
Find cheap flights from Illinois to Colorado with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.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 January 2, 2025.
Round-trip from | $74 (Frontier) |
|---|---|
One-way from | $43 (Cheapflightsfares) |
Find flight deals from Illinois to Colorado
Cheapest flights from Illinois to ColoradoExplore 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 January 2, 2025.
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 January 2, 2025.
This Frontier deal was found by Cheapflights users on 1/1. 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.
This Frontier deal was found by Cheapflights users on 1/1. 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.
This Frontier deal was found by Cheapflights users on 1/1. 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.
This American Airlines deal was found by Cheapflights users on 1/2. 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.
This Southwest deal was found by Cheapflights users on 12/31. 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.
This Southwest deal was found by Cheapflights users on 1/1. 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.
This Orbitz deal was found by Cheapflights users on 1/1. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
This American Airlines deal was found by Cheapflights users on 1/1. 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.
This Delta deal was found by Cheapflights users on 1/1. 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.
This Delta deal was found by Cheapflights users on 1/1. 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.
This Delta deal was found by Cheapflights users on 1/1. 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.
This Southwest deal was found by Cheapflights users on 1/1. 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.
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 2,558,603 searches. Data last updated January 2, 2025.
Fly from
Fly to
Route
Depart
Return
Price
St. LouisDenver
STL - DEN
STLDEN
Lambert-St Louis
Mon 1/20
7:09 pm-8:37 pm
Nonstop2h 28m
Denver Intl
Sat 2/1
6:00 am-9:16 am
Nonstop2h 16m
ChicagoDenver
MDW - DEN
MDWDEN
Chicago Midway
Tue 2/18
7:05 am-8:59 am
Nonstop2h 54m
Denver Intl
Mon 2/24
8:55 pm-12:17 am
Nonstop2h 22m
ChicagoDenver
ORD - DEN
ORDDEN
Chicago O'Hare Intl
Tue 2/18
6:50 am-8:53 am
Nonstop3h 03m
Denver Intl
Mon 2/24
9:08 pm-12:44 am
Nonstop2h 36m
ChicagoDenver
ORD - DEN
ORDDEN
Chicago O'Hare Intl
Tue 2/11
8:42 am-10:34 am
Nonstop2h 52m
Denver Intl
Sat 2/15
7:00 am-10:23 am
Nonstop2h 23m
ChicagoDenver
ORD - DEN
ORDDEN
Chicago O'Hare Intl
Sun 2/2
7:10 pm-9:05 pm
Nonstop2h 55m
Denver Intl
Wed 2/5
7:05 pm-10:35 pm
Nonstop2h 30m
ChicagoDenver
ORD - DEN
ORDDEN
Chicago O'Hare Intl
Wed 2/5
7:10 am-9:00 am
Nonstop2h 50m
Denver Intl
Mon 2/10
7:45 am-11:20 am
Nonstop2h 35m
St. LouisDenver
STL - DEN
STLDEN
Lambert-St Louis
Wed 2/5
8:35 pm-10:05 pm
Nonstop2h 30m
Denver Intl
Sat 2/8
7:10 am-10:20 am
Nonstop2h 10m
ChicagoDenver
MDW - DEN
MDWDEN
Chicago Midway
Sat 1/25
7:20 pm-9:10 pm
Nonstop2h 50m
Denver Intl
Mon 1/27
6:30 pm-9:45 pm
Nonstop2h 15m
ChicagoDenver
ORD - DEN
ORDDEN
Chicago O'Hare Intl
Sat 2/15
6:32 pm-8:38 pm
Nonstop3h 06m
Denver Intl
Sun 2/16
1:20 pm-6:07 am
1 stop15h 47m
St. LouisDenver
STL - DEN
STLDEN
Lambert-St Louis
Wed 1/29
11:38 am-5:47 pm
1 stop7h 09m
Denver Intl
Wed 2/5
10:15 am-5:22 pm
1 stop6h 07m
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.
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 $278). 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 January 2, 2025.
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 January 2, 2025.
The most flights from USIL to USCO are scheduled on a Monday (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 January 2, 2025.
Peruse reviews from past customers who have flown with Frontier, Southwest and Delta 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.
Boarding
Food
Crew
Overall
Entertainment
Comfort
Reviews
We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.
Boarding
Food
Crew
Overall
Entertainment
Comfort
Reviews
We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.
Boarding
Food
Crew
Overall
Entertainment
Comfort
Reviews
We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.
Boarding
Food
Crew
Overall
Entertainment
Comfort
Reviews
We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.
Boarding
Food
Crew
Overall
Entertainment
Comfort
Reviews
We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.
Boarding
Food
Crew
Overall
Entertainment
Comfort
Reviews
We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.
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.
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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.
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 2,558,603 searches. Data last updated January 2, 2025.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$40 | Average$155 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$92 | Average$175 | FlexibilityNo cancel fee | On-time88% | |
| Cheapest$139 | Average$433 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$152 | Average$487 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$157 | Average$312 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$185 | Average$459 | FlexibilityNo cancel fee | On-timeN/A |