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$39+ Cheap flights from Denver (DEN) 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
Mon 11/25
Mon 12/2
1 adult, Economy
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Cheap flight deals from Denver to Illinois

Discover tips and strategies to find the most affordable flight options for your journey from Denver (DEN) 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 Denver to Illinois

Cheapest flights from Denver to Illinois
Explore the most affordable flight options available from Denver 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.
Thu 12/1210:26 amDEN - ORD
Nonstop2h 34mFrontier
Mon 12/167:25 amORD - DEN
Nonstop3h 01mFrontier
Deal found 11/19$77
This Cheapflightsfares deal was found by Cheapflights users on 11/18. 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 12/98:55 pmDEN - MDW
Nonstop2h 18mFrontier
Thu 12/127:15 amMDW - DEN
Nonstop2h 50mFrontier
Deal found 11/18$77
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 12/75:05 amDEN - STL
Nonstop2h 08mFrontier
Mon 12/96:46 pmSTL - DEN
Nonstop2h 36mFrontier
Deal found 11/19$77
This Gotogate 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/1312:23 pmDEN - PIA
Nonstop1h 59mAllegiant Air
Sat 12/219:08 amPIA - DEN
Nonstop2h 25mAllegiant Air
Deal found 11/19$90
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

Find flights from Denver to Illinois within your budget

Customize your flight search to find flights from Denver 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

DenverPeoria

DEN - PIA

DENPIA

Denver Intl

Fri 12/13

12:23 pm-3:22 pm

Nonstop1h 59m

Greater Peoria

Sat 12/21

9:08 am-10:33 am

Nonstop2h 25m

$90

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

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 Denver to Illinois

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

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

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

Currently, September is the cheapest month in which you can book a flight from Denver to Illinois (average of $232). Flying from Denver 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 DEN to IL?

Find hourly flight availability from Denver 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 Denver to Illinois as you normally would.

Weekly flight availability from Denver to Illinois

Explore weekly flight availability from Denver 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 DEN 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.
Get a feel of what it's like to fly with Frontier, Southwest and Delta from Denver to Illinois by reading reviews from past customers. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
5,014 reviews

Boarding

8.2

Crew

8.7

Food

7.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Reviews

1 / 10

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

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

Boarding

8.2

Crew

8.7

Food

7.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Reviews

1 / 10

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

Alaska Airlines
8.0
Very good
9,461 reviews
Southwest
8.1
Very good
5,014 reviews

Boarding

8.2

Crew

8.7

Food

7.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Reviews

1 / 10

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

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

Boarding

8.2

Crew

8.7

Food

7.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Reviews

1 / 10

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

United Airlines
7.4
Good
9,171 reviews
Southwest
8.1
Very good
5,014 reviews

Boarding

8.2

Crew

8.7

Food

7.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

Reviews

1 / 10

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

Allegiant Air
7.4
Good
850 reviews
Southwest
8.1
Very good
5,014 reviews

Boarding

8.2

Crew

8.7

Food

7.2

Entertainment

7.7

Comfort

8.1

Overall

8.1

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 Denver to Illinois. 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 from for flights from Denver to Illinois?

    Most people fly from Denver Intl (DEN) if they book a flight from Denver to Illinois. Denver Intl is conveniently located just 18.5 mi from Denver’s city center.

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

    $39 is the cheapest one-way deal found within the past few days, from Frontier. You may also be able to find cheap deals on Allegiant Air and United Airlines, with prices starting from $58 and $79, respectively.

  • What are the most popular routes from Denver to Illinois?

    When deciding which route to take from Denver to Illinois consider Denver Intl - Chicago O'Hare Intl, Denver Intl - Chicago Midway or Denver Intl - Lambert-St Louis as they are the most popular.

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

    No one likes to see their flight delayed. When booking a flight from Denver to Illinois consider choosing Japan Airlines (94%), Cathay Pacific (93%) or Brussels Airlines (92%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Denver to Illinois?

    Looking at all options, your cheapest flight can be booked for $39. While the most popular route (Denver Intl - Chicago O'Hare Intl) can be booked for $121 on average our data indicates $1,113 when flying from Denver to Illinois.

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

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

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

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

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

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

    Currently, September is the cheapest month in which you can book a flight from Denver to Illinois (average of $232). Flying from Denver 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.

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Alternative routes for Denver to Illinois

See prices for flight routes from nearby airports that may be better suited for you.
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Denver to John F Kennedy Intl flights
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Denver to Salt Lake City flights
Denver to Lihue flights
Denver to Indianapolis flights
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Denver to Cincinnati flights
Denver to San Jose flights
Denver to Jacksonville flights
Denver to Grand Rapids flights
Denver to Charleston flights

Top 6 airlines flying from Denver to Illinois

Discover the top 6 airlines that operate flights from Denver 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$378FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$140Average$237FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$144Average$364FlexibilityNo cancel feeOn-time69%
DeltaCheapest$189Average$472FlexibilityNo cancel feeOn-timeN/A
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