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$63+ Cheap flights from Chicago (CHI) to Denver (DEN)

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 10/24. Fares are subject to change and may not be available on all flights or dates of travel.
CHI — DEN
oct. 17 — oct. 241
ven. 10/17
ven. 10/24
1 adult, Economy
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Cheapflights Tip: The best prices from Chicago to Denver Intl are usually found in November or October, booked 30 days in advance, depart on a Wednesday or Saturday and return on a Friday

Cheap flight deals from Chicago to Denver

Discover tips and strategies to find the most affordable flight options for your journey from Chicago (CHI) to Denver (DEN). 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 septembre 17, 2025.

Round-trip from

$93
(Frontier)

One-way from

$63
(Cheapflightsfares)

Popular in

December

Cheapest in

November

Average price

$181

Good round-trip deal

$151 or less

Good one-way deal

$107 or less
From Chicago (CHI) to Denver Intl
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One-way flight from Chicago (CHI) to Denver Intl
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High demand for flights, 1% potential price rise
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Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Price to beat on a round-trip flight from Chicago (CHI) to Denver Intl.
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Price to beat on a one-way flight from Chicago (CHI) to Denver Intl.
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Find flight deals from Chicago to Denver

Cheapest flights from Chicago to Denver
Explore the most affordable flight options available from Chicago to Denver. Find the lowest fares from popular airlines and budget airlines, with prices last updated on septembre 17, 2025.

This CheapOair deal was found by Cheapflights users on 9/16. 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.
jeu. 11/66:00 amORD - DEN
Nonstop2h 41mFrontier
dim. 11/98:48 pmDEN - ORD
Nonstop2h 31mFrontier
Deal found 9/16$93
This Frontier deal was found by Cheapflights users on 9/16. 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.
ven. 11/712:30 pmMDW - DEN
Nonstop2h 46mFrontier
lun. 11/108:05 amDEN - MDW
Nonstop2h 25mFrontier
Deal found 9/16$93
This Cheapflightsfares deal was found by Cheapflights users on 9/16. 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.
sam. 10/117:05 amORD - DEN
Nonstop2h 49mFrontier
ven. 10/171:42 pmDEN - ORD
1 stop8h 57mFrontier
Deal found 9/16$94
This Frontier deal was found by Cheapflights users on 9/16. 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.
ven. 10/2410:51 amORD - DEN
Nonstop2h 47mFrontier
sam. 10/2512:05 pmDEN - ORD
1 stop7h 09mFrontier
Deal found 9/16$96
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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.
mar. 10/77:15 amORD - DEN
Nonstop2h 49mFrontier
sam. 10/118:22 pmDEN - ORD
Nonstop2h 31mFrontier
Deal found 9/15$97
This Priceline deal was found by Cheapflights users on 9/15. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mer. 10/87:15 amORD - DEN
Nonstop2h 49mFrontier
sam. 10/118:22 pmDEN - ORD
Nonstop2h 31mFrontier
Deal found 9/15$98
This Frontier deal was found by Cheapflights users on 9/16. 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.
ven. 11/712:30 pmMDW - DEN
Nonstop2h 46mFrontier
sam. 11/812:25 pmDEN - MDW
1 stop8h 10mFrontier
Deal found 9/16$98
This Cheapflightsfares deal was found by Cheapflights users on 9/16. 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.
mer. 11/57:20 amORD - DEN
Nonstop2h 49mFrontier
lun. 11/106:25 amDEN - ORD
1 stop6h 39mFrontier
Deal found 9/16$99
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
mer. 10/227:15 amORD - DEN
Nonstop2h 49mFrontier
dim. 10/266:00 amDEN - ORD
Nonstop2h 36mFrontier
Deal found 9/15$100
This Frontier deal was found by Cheapflights users on 9/16. 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.
sam. 10/255:28 pmORD - DEN
1 stop7h 15mFrontier
sam. 11/18:41 pmDEN - ORD
Nonstop2h 31mFrontier
Deal found 9/16$101
This Kiwi.com deal was found by Cheapflights users on 9/16. 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.
ven. 11/1412:30 pmMDW - DEN
Nonstop2h 46mFrontier
lun. 11/178:05 amDEN - MDW
Nonstop2h 25mFrontier
Deal found 9/16$101
This Booking.com deal was found by Cheapflights users on 9/16. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ven. 11/76:00 amORD - DEN
Nonstop2h 41mFrontier
ven. 11/712:59 amDEN - ORD
1 stop21h 30mFrontier
Deal found 9/16$102

Cheapflights Fare Finder

 
Customize your flight search to find flights from Chicago to Denver 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 septembre 17, 2025.
Use the filters below to find and compare flights from Chicago to Denver that are best for you.

Fly from

Chicago

Fly to

Denver

Route

Depart

Return

Price

ChicagoDenver

MDW - DEN

MDWDEN

Chicago Midway

mer. 10/15

8:00 am-9:45 am

Nonstop2h 45m

Denver Intl

sam. 10/18

5:40 am-9:00 am

Nonstop2h 20m

$157

ChicagoDenver

ORD - DEN

ORDDEN

Chicago O'Hare Intl

mar. 10/21

1:00 pm-2:42 pm

Nonstop2h 42m

Denver Intl

sam. 10/25

9:36 am-1:12 pm

Nonstop2h 36m

$157

ChicagoDenver

MDW - DEN

MDWDEN

Chicago Midway

jeu. 12/4

7:05 am-8:45 am

Nonstop2h 40m

Denver Intl

mar. 12/9

8:00 am-11:25 am

Nonstop2h 25m

$157

ChicagoDenver

MDW - DEN

MDWDEN

Chicago Midway

mar. 10/21

8:40 pm-10:20 pm

Nonstop2h 40m

Denver Intl

sam. 10/25

7:15 pm-10:35 pm

Nonstop2h 20m

$157

ChicagoDenver

MDW - DEN

MDWDEN

Chicago Midway

jeu. 12/25

11:25 am-2:55 pm

1 stop4h 30m

Denver Intl

mar. 12/30

5:20 am-8:45 am

Nonstop2h 25m

$167

ChicagoDenver

ORD - DEN

ORDDEN

Chicago O'Hare Intl

mar. 10/28

1:50 pm-8:40 pm

1 stop7h 50m

Denver Intl

jeu. 10/30

7:35 pm-11:05 pm

Nonstop2h 30m

$167

ChicagoDenver

ORD - DEN

ORDDEN

Chicago O'Hare Intl

sam. 11/1

7:00 am-8:45 am

Nonstop2h 45m

Denver Intl

mar. 11/4

7:30 am-3:25 pm

1 stop6h 55m

$167

ChicagoDenver

MDW - DEN

MDWDEN

Chicago Midway

mer. 10/15

5:55 pm-10:05 pm

1 stop5h 10m

Denver Intl

mer. 10/22

12:20 pm-5:15 pm

1 stop3h 55m

$177

ChicagoDenver

ORD - DEN

ORDDEN

Chicago O'Hare Intl

sam. 11/8

2:15 pm-9:40 pm

2 stops8h 25m

Denver Intl

lun. 11/10

6:50 am-1:00 pm

1 stop5h 10m

$178

ChicagoDenver

ORD - DEN

ORDDEN

Chicago O'Hare Intl

ven. 10/10

5:01 am-6:41 am

Nonstop2h 40m

Denver Intl

mar. 10/14

4:45 pm-8:25 pm

Nonstop2h 40m

$179

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 41 results
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The best insider tips for Chicago to Denver flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Chicago to Denver trip
Airlines
Frontier

Frontier's UpFront Plus guarantees an empty middle seat, enhancing comfort for a fee.


Frontier's Economy Bundle includes a carry-on, seat selection, and no change fees.

Read more about Frontierby Marisa Garcia
Southwest

Southwest offers free in-flight entertainment streamed to your device, enhancing travel enjoyment.


Southwest's Rapid Rewards program offers points for every dollar spent, redeemable for free flights.

Read more about Southwestby Marisa Garcia
United Airlines

United's Economy Plus offers extra legroom seats, ideal for added comfort on domestic flights.


United's MileagePlus allows pooling miles, a great way to gather enough for a ticket.

Read more about United Airlinesby Harriet Baskas
Airports
ORD

Use the free shuttle train at ORD to navigate between terminals efficiently, especially if you have a tight connection.

Read more about ORDby Ramsey Qubein
MDW

Order food via MDW's mobile system to your gate to avoid missing Southwest's open seating boarding process.

Read more about MDWby Ramsey Qubein
DEN

Take the A Line train from DEN to Union Station for a cost-effective and efficient trip to downtown Denver.

Read more about DENby Emily Zemler
Our travel experts
Marisa Garcia

Marisa Garcia

Expert on Frontier and Southwest

Marisa Garcia

Marisa Garcia

Marisa knows planes inside and out, spending 16 years working on aircraft in hangars at airports around the world. She is an aviation industry expert, specialized in airline interiors and regulations. Ten years ago, she pivoted to journalism. She shares her insights in leading aviation, travel, and business publications and on her site FlightChic.

Read more
Harriet Baskas

Harriet Baskas

Expert on United Airlines

Harriet Baskas

Harriet Baskas

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Read more
Ramsey Qubein

Ramsey Qubein

Expert on ORD and MDW

Ramsey Qubein

Ramsey Qubein

An avid traveler and aviation expert who has visited 173 countries, all 50 states and seven continents, Ramsey Qubein flies nearly 400,000 miles a year. As a North Carolina-based freelance journalist for publications including Conde Nast Traveler, Forbes, USA Today and Bloomberg among others, he explores the latest trends in aviation, hospitality, cruises and business.

Read more
Emily Zemler

Emily Zemler

Expert on DEN

Emily Zemler

Emily Zemler

Emily is a freelance writer and book author based in London covering entertainment and travel. Her work has appeared in Los Angeles Times, Observer, and Conde Nast Traveler She has ventured to more than 40 countries and all seven continents, always in search of a great art museum. She has written extensively about hotels, luxury travel, and aviation.

Read more

Best time to book a flight from Chicago to Denver

Have a flexible travel schedule? Discover the best time to fly to Denver from Chicago 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.

Cheapflights Insights

Everything you need to know about your flight from Chicago to Denver

How far ahead should I book a flight from Chicago to Denver?

Use this chart to determine the optimal time to book a round-trip flight from Chicago to Denver. Price data was last updated on September 12, 2025.

The price you pay for your flight from Chicago to Denver may vary depending on when you book. For the best chance of a lower fare, look to book 30 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from Chicago to Denver?

Currently, October is the cheapest month in which you can book a flight from Chicago to Denver (average of $197). Flying from Chicago to Denver 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 CHI to DEN?

Find hourly flight availability from Chicago to Denver. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated septembre 17, 2025.

A simple way to save on the total cost of your ticket is to fly from Chicago to Denver in the morning. If you’re flexible enough to do this you can expect to save up to 16% on your trip compared to booking a flight at noon.

What is the cheapest day to fly from Chicago to Denver?

Use this chart to determine the cheapest time to fly round-trip from Chicago to Denver. Price data was last updated on September 14, 2025.

Travelers seeking maximum savings on their Chicago to Denver flight should consider departing on Saturday afternoons when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Chicago to Denver

Explore weekly flight availability from Chicago to Denver. 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 septembre 17, 2025.

The most flights from CHI to DEN are scheduled on a Monday (76 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (43 on average).

How much does it cost to fly round-trip from Chicago to Denver?

Reviews of airlines servicing Denver

Get insights into the airlines that provide service to Denver. 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 Denver. Reviews last updated septembre 17, 2025.
Peruse reviews from past customers who have flown with Southwest, United Airlines, and American Airlines from Chicago to Denver 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
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
Southwest
8.0
Very good
4,242 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
United Airlines
7.4
Good
8,926 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
Frontier
5.8
Fair
3,173 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.

Related info for your journey

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

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

    Denver Intl (DEN), located 18.5 mi from the city center, is the airport you fly into when you book flights from Chicago to Denver. 4 airlines have flights to Denver Intl from Chicago on a regular basis. Booking flights from Chicago to Denver Intl should not be difficult; the airport handles an average of 61 inbound flights from Chicago per day.

  • How long is the flight from Chicago to Denver?

    A quick flight from Chicago to Denver can take about 2h 42m. Southwest provides one of the quickest options available for as low as $157. There are 886 mi between Chicago and Denver. Generally, flights for this route are nonstop.

  • What are the cheapest airlines flying from Chicago to Denver round-trip?

    Frontier, at $58, was found to be the cheapest airline from Chicago to Denver.Alternate airlines to your destination round-trip include American Airlines and Southwest. Users have found that Frontier is 70% cheaper than the other options available to this destination.

  • What are the most reliable airlines from Chicago to Denver?

    The top 3 most reliable airlines when flying from Chicago to Denver are Frontier (85%), United Airlines (74%) and Copa Airlines (70%).

  • What are the cheapest flights from Chicago to Denver?

    Looking at all options, your cheapest flight can be booked for $67. While the most popular route (Chicago O'Hare Intl - Denver Intl) can be booked for $77 on average, our data indicates $490 when flying from Chicago to Denver.

  • Can I find deals for flights from Chicago to Denver that include hotel bookings?

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

  • How can I find direct flights from Chicago to Denver?

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

  • Can I find deals for business class flights from Chicago to Denver?

    Yes. Cheapflights offers flight deals from Chicago to Denver 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 Chicago to Denver?

    Currently, October is the cheapest month in which you can book a flight from Chicago to Denver (average of $197). Flying from Chicago to Denver 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.

See more FAQs

Traveling to a place near Denver?

Book flights to Denver if you plan to visit one of these locations
Black Hawk
Westminster
Golden
Winter Park
Lakewood
Broomfield
Greeley
Lone Tree
Cripple Creek
Thornton
Silverthorne
Manitou Springs
Fort Morgan
Glendale
Wheat Ridge
Brighton
Longmont
Idaho Springs
Parker
Sterling

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Alternative routes for Chicago to Denver

See prices for flight routes from nearby airports that may be better suited for you.
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Top 4 airlines flying from Chicago to Denver

Discover the top 4 airlines that operate flights from Chicago to Denver. 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 septembre 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$58Average$156FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$152Average$231FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$157Average$253FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$161Average$292FlexibilityNo cancel feeOn-time69%

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