$34+ 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 9/26. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — ORD
Sep 28 — Oct 51
Round-trip
1 adult, Economy
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Find cheap flights from Denver to Illinois 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
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Cheapest flights from Denver to IllinoisExplore 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 August 29, 2026.
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 August 29, 2026.
This Super.com deal was found by Cheapflights users on 8/27. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/214:12 pm -
Nonstop2h 05m
Fri 9/258:10 pm -
Nonstop2h 29m
Deal found 8/27![Frontier logo]()
$138
This Kiwi.com deal was found by Cheapflights users on 8/28. 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.
Wed 10/1412:21 pm -
Nonstop2h 03m
Fri 10/166:35 pm -
1 stop14h 31m
Deal found 8/28![Frontier logo]()
$140
This Super.com deal was found by Cheapflights users on 8/27. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/176:40 am -
1 stop8h 44m
Fri 9/188:10 pm -
Nonstop2h 29m
Deal found 8/27![Frontier logo]()
$141
This Kiwi.com deal was found by Cheapflights users on 8/28. 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.
Sat 10/39:19 pm -
2 stops38h 51m
Sat 10/107:42 pm -
Nonstop2h 27m
Deal found 8/28![Frontier logo]()
$142
This CheapOair deal was found by Cheapflights users on 8/27. 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.
Fri 9/184:12 pm -
Nonstop2h 05m
Tue 9/2212:17 pm -
1 stop7h 16m
Deal found 8/27![Frontier logo]()
$144
This Frontier deal was found by Cheapflights users on 8/29. 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.
Mon 9/2810:50 pm -
1 stop11h 42m
Sat 10/38:10 pm -
Nonstop2h 29m
Deal found 8/29![Frontier logo]()
$145
This Expedia deal was found by Cheapflights users on 8/28. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/309:19 pm -
1 stop11h 16m
Wed 10/144:19 pm -
Nonstop2h 33m
Deal found 8/28![Frontier logo]()
$146
This FlightHub deal was found by Cheapflights users on 8/27. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/147:31 am -
1 stop27h 00m
Mon 10/198:00 pm -
Nonstop2h 39m
Deal found 8/27![Frontier logo]()
$147
This Expedia deal was found by Cheapflights users on 8/26. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/254:12 pm -
Nonstop2h 05m
Fri 10/25:19 pm -
1 stop15h 33m
Deal found 8/26![Frontier logo]()
$149
This Kiwi.com deal was found by Cheapflights users on 8/26. 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.
Fri 10/164:12 pm -
Nonstop2h 03m
Mon 10/196:35 pm -
1 stop14h 31m
Deal found 8/26![Frontier logo]()
$151
This Kiwi.com deal was found by Cheapflights users on 8/26. 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.
Wed 9/234:12 pm -
Nonstop2h 05m
Wed 9/302:29 pm -
2 stops22h 30m
Deal found 8/26![Frontier logo]()
$154
This Cheapflightsfares deal was found by Cheapflights users on 8/24. 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 9/177:12 pm -
1 stop26h 47m
Sat 9/196:30 am -
Nonstop2h 45m
Deal found 8/24![Frontier logo]()
$162
Best flights from Denver to IllinoisDiscover carefully curated flight deals from Denver to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 29, 2026.
Discover carefully curated flight deals from Denver to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 29, 2026.
This Southwest deal was found by Cheapflights users on 8/25. 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.
Mon 10/1911:20 am -
1 stop4h 55m
Wed 10/217:20 pm -
Nonstop2h 35m
Deal found 8/25![Southwest logo]()
$219
This Delta deal was found by Cheapflights users on 8/25. 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 9/196:30 am -
1 stop5h 09m
Tue 9/222:00 pm -
1 stop7h 05m
Deal found 8/25![Delta logo]()
$233
This United Airlines deal was found by Cheapflights users on 8/24. 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 9/165:32 pm -
Nonstop2h 06m
Thu 9/175:10 am -
Nonstop2h 33m
Deal found 8/24![United Airlines logo]()
$234
This Kiwi.com deal was found by Cheapflights users on 8/28. 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.
Thu 11/510:37 pm -
1 stop10h 56m
Sun 11/88:37 pm -
1 stop28h 12m
Deal found 8/28![Multiple Airlines logo]()
$280
This KAYAK deal was found by Cheapflights users on 8/24. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/153:13 pm -
1 stop5h 51m
Thu 9/1710:30 pm -
Nonstop2h 47m
Deal found 8/24![American Airlines logo]()
$315
This Sun Country Air deal was found by Cheapflights users on 8/24. 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 12/2910:08 am -
1 stop6h 34m
Thu 12/3111:53 am -
1 stop7h 27m
Deal found 8/24![Sun Country Air logo]()
$315
This Southwest deal was found by Cheapflights users on 8/27. 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 10/312:30 pm -
1 stop4h 30m
Mon 10/56:05 am -
Nonstop2h 40m
Deal found 8/27![Southwest logo]()
$219
This Delta deal was found by Cheapflights users on 8/25. 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.
Thu 9/1712:50 am -
1 stop7h 10m
Sat 9/196:40 am -
1 stop8h 17m
Deal found 8/25![Delta logo]()
$233
This Southwest deal was found by Cheapflights users on 8/24. 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 11/76:00 am -
2 stops7h 30m
Mon 11/912:45 pm -
1 stop4h 50m
Deal found 8/24![Southwest logo]()
$234
This United Airlines deal was found by Cheapflights users on 8/25. 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.
Thu 12/317:09 pm -
Nonstop2h 32m
Sun 1/39:12 pm -
Nonstop3h 00m
Deal found 8/25![United Airlines logo]()
$264
This Delta deal was found by Cheapflights users on 8/25. 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.
Fri 12/46:15 am -
1 stop5h 46m
Tue 12/89:37 am -
1 stop6h 31m
Deal found 8/25![Delta logo]()
$245
This Kiwi.com deal was found by Cheapflights users on 8/27. 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.
Thu 11/1210:37 pm -
1 stop10h 56m
Sun 11/158:37 pm -
1 stop14h 11m
Deal found 8/27![Multiple Airlines logo]()
$283
This Southwest deal was found by Cheapflights users on 8/25. 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 10/2810:45 am -
2 stops5h 05m
Mon 11/210:05 am -
1 stop4h 20m
Deal found 8/25![Southwest logo]()
$234
This United Airlines deal was found by Cheapflights users on 8/25. 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 9/165:48 pm -
Nonstop2h 42m
Sun 9/205:55 am -
Nonstop2h 39m
Deal found 8/25![United Airlines logo]()
$274
This Southwest deal was found by Cheapflights users on 8/24. 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.
Fri 10/1611:20 am -
1 stop4h 55m
Tue 10/201:05 pm -
1 stop4h 25m
Deal found 8/24![Southwest logo]()
$236
This American Airlines deal was found by Cheapflights users on 8/25. 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 10/17:16 am -
1 stop4h 33m
Sun 10/45:02 am -
1 stop6h 00m
Deal found 8/25![American Airlines logo]()
$319
This Kiwi.com deal was found by Cheapflights users on 8/29. 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.
Thu 10/2910:37 pm -
1 stop11h 50m
Sun 11/18:53 pm -
1 stop13h 55m
Deal found 8/29![Multiple Airlines logo]()
$301
This United Airlines deal was found by Cheapflights users on 8/25. 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.
Fri 9/185:30 am -
Nonstop2h 42m
Sun 9/205:00 am -
Nonstop2h 39m
Deal found 8/25![United Airlines logo]()
$286
This American Airlines deal was found by Cheapflights users on 8/29. 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.
Sat 9/197:16 am -
1 stop4h 33m
Sat 10/35:02 am -
1 stop4h 35m
Deal found 8/29![American Airlines logo]()
$319
This Southwest deal was found by Cheapflights users on 8/27. 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.
Fri 11/64:10 pm -
1 stop4h 50m
Mon 11/912:45 pm -
1 stop4h 50m
Deal found 8/27![Southwest logo]()
$240
This Delta deal was found by Cheapflights users on 8/25. 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 11/187:05 am -
1 stop8h 28m
Sat 11/215:13 pm -
1 stop7h 02m
Deal found 8/25![Delta logo]()
$299
This Kiwi.com deal was found by Cheapflights users on 8/24. 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.
Thu 10/2210:44 pm -
1 stop11h 43m
Sun 10/258:53 pm -
1 stop19h 11m
Deal found 8/24![Multiple Airlines logo]()
$302
This American Airlines deal was found by Cheapflights users on 8/27. 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.
Fri 9/111:17 pm -
1 stop7h 29m
Tue 9/155:00 am -
2 stops10h 21m
Deal found 8/27![American Airlines logo]()
$322
This United Airlines deal was found by Cheapflights users on 8/24. 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.
Sat 11/214:48 pm -
1 stop5h 36m
Thu 11/268:30 am -
1 stop5h 15m
Deal found 8/24![United Airlines logo]()
$297
This Delta deal was found by Cheapflights users on 8/24. 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.
Fri 10/232:35 pm -
1 stop6h 55m
Wed 11/41:00 pm -
1 stop8h 11m
Deal found 8/24![Delta logo]()
$299
This Southwest deal was found by Cheapflights users on 8/24. 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.
Fri 10/238:55 pm -
Nonstop2h 20m
Sun 10/258:30 am -
Nonstop2h 40m
Deal found 8/24![Southwest logo]()
$256
This American Airlines deal was found by Cheapflights users on 8/29. 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.
Sat 9/191:17 pm -
1 stop7h 51m
Tue 9/225:02 am -
2 stops10h 19m
Deal found 8/29![American Airlines logo]()
$324
This Kiwi.com deal was found by Cheapflights users on 8/25. 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.
Wed 9/910:38 am -
1 stop27h 25m
Sun 9/133:53 pm -
1 stop26h 23m
Deal found 8/25![Multiple Airlines logo]()
$327
This United Airlines deal was found by Cheapflights users on 8/28. 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.
Thu 10/88:29 pm -
Nonstop2h 30m
Thu 10/155:00 am -
Nonstop2h 39m
Deal found 8/28![United Airlines logo]()
$298
This Delta deal was found by Cheapflights users on 8/27. 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.
Fri 10/162:36 pm -
1 stop7h 00m
Mon 10/194:26 pm -
1 stop7h 46m
Deal found 8/27![Delta logo]()
$319
Last-minute flights from Denver to IllinoisDiscover last-minute flight deals from Denver to Illinois. Data last updated August 29, 2026 and is based on user searches.
Discover last-minute flight deals from Denver to Illinois. Data last updated August 29, 2026 and is based on user searches.
This Super.com deal was found by Cheapflights users on 8/27. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/176:40 am -
1 stop8h 44m
Fri 9/188:10 pm -
Nonstop2h 29m
Deal found 8/27![Frontier logo]()
$141
This CheapOair deal was found by Cheapflights users on 8/27. 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.
Fri 9/184:12 pm -
Nonstop2h 05m
Tue 9/2212:17 pm -
1 stop7h 16m
Deal found 8/27![Frontier logo]()
$144
This Super.com deal was found by Cheapflights users on 8/28. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/198:55 pm -
Nonstop2h 28m
Mon 9/216:30 am -
Nonstop2h 45m
Deal found 8/28![Frontier logo]()
$162
This Cheapflightsfares deal was found by Cheapflights users on 8/27. 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 9/198:55 pm -
Nonstop2h 28m
Sun 9/278:55 pm -
1 stop14h 12m
Deal found 8/27![Frontier logo]()
$163
This Frontier deal was found by Cheapflights users on 8/27. 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.
Sat 9/194:11 pm -
1 stop5h 53m
Tue 9/226:30 am -
Nonstop2h 45m
Deal found 8/27![Frontier logo]()
$164
This Super.com deal was found by Cheapflights users on 8/27. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/214:12 pm -
Nonstop2h 05m
Fri 9/258:10 pm -
Nonstop2h 29m
Deal found 8/27![Frontier logo]()
$138
This Kiwi.com deal was found by Cheapflights users on 8/26. 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.
Wed 9/234:12 pm -
Nonstop2h 05m
Wed 9/302:29 pm -
2 stops22h 30m
Deal found 8/26![Frontier logo]()
$154
This Frontier deal was found by Cheapflights users on 8/27. 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.
Wed 9/239:19 pm -
1 stop11h 16m
Thu 9/246:39 pm -
1 stop13h 58m
Deal found 8/27![Frontier logo]()
$158
This Expedia deal was found by Cheapflights users on 8/26. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/254:12 pm -
Nonstop2h 05m
Fri 10/25:19 pm -
1 stop15h 33m
Deal found 8/26![Frontier logo]()
$149
This Frontier deal was found by Cheapflights users on 8/25. 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.
Sat 9/269:19 pm -
1 stop11h 16m
Mon 9/285:19 pm -
1 stop15h 33m
Deal found 8/25![Frontier logo]()
$159
This Frontier deal was found by Cheapflights users on 8/29. 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.
Mon 9/2810:50 pm -
1 stop11h 42m
Sat 10/38:10 pm -
Nonstop2h 29m
Deal found 8/29![Frontier logo]()
$145
This Expedia deal was found by Cheapflights users on 8/28. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/309:19 pm -
1 stop11h 16m
Wed 10/144:19 pm -
Nonstop2h 33m
Deal found 8/28![Frontier logo]()
$146
One-way flights from Denver to IllinoisSearch for one-way flight options from Denver to Illinois. Find affordable one-way fares based on user searches. Data last updated August 29, 2026.
Search for one-way flight options from Denver to Illinois. Find affordable one-way fares based on user searches. Data last updated August 29, 2026.
This Cheapflightsfares deal was found by Cheapflights users on 8/27. 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 9/264:12 pm -
Nonstop2h 05m
Deal found 8/27![Frontier logo]()
$34
This Super.com deal was found by Cheapflights users on 8/27. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/144:12 pm -
Nonstop2h 05m
Deal found 8/27![Frontier logo]()
$44
This Kiwi.com deal was found by Cheapflights users on 8/27. 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.
Sat 10/243:54 pm -
Nonstop2h 03m
Deal found 8/27![Frontier logo]()
$54
This Super.com deal was found by Cheapflights users on 8/26. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/24:12 pm -
Nonstop2h 05m
Deal found 8/26![Frontier logo]()
$61
This Expedia deal was found by Cheapflights users on 8/26. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/254:12 pm -
Nonstop2h 05m
Deal found 8/26![Frontier logo]()
$62
This Kiwi.com deal was found by Cheapflights users on 8/24. 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 9/157:10 pm -
1 stop17h 00m
Deal found 8/24![Frontier logo]()
$70
This Super.com deal was found by Cheapflights users on 8/27. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/214:15 pm -
Nonstop2h 05m
Deal found 8/27![Frontier logo]()
$76
This CheapOair deal was found by Cheapflights users on 8/25. 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 9/102:16 pm -
Nonstop2h 03m
Deal found 8/25![Allegiant Air logo]()
$77
This Frontier deal was found by Cheapflights users on 8/27. 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.
Fri 10/234:12 pm -
Nonstop2h 03m
Deal found 8/27![Frontier logo]()
$77
This Super.com deal was found by Cheapflights users on 8/24. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/246:40 am -
1 stop10h 14m
Deal found 8/24![Frontier logo]()
$78
This Kiwi.com deal was found by Cheapflights users on 8/28. 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 9/297:10 pm -
1 stop17h 00m
Deal found 8/28![Frontier logo]()
$80
This Cheapflightsfares deal was found by Cheapflights users on 8/27. 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 10/1510:20 am -
Nonstop1h 59m
Deal found 8/27![Allegiant Air logo]()
$101
Find flight deals from Denver to Illinois
Keep the following information in mind while searching for Denver to Illinois flight deals. Data was last updated August 29, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $138 (Super.com) |
One-way from | $34 (Cheapflightsfares) |
Popular in | July |
Cheapest in | January |
Average price | $277 |
Good round-trip deal | $242 or less |
Good one-way deal | $145 or less |
Cheapflights Fare Finder
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 7,457,451 searches. Data last updated August 29, 2026.
Use the filters below to find and compare flights from Denver to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
DenverChicago
DEN Denver Intl - MDW Chicago Midway
DENMDW
Denver Intl
Mon 10/19
11:20 am-5:15 pm
1 stop4h 55m
Chicago Midway
Wed 10/21
7:20 pm-8:55 pm
Nonstop2h 35m
$219
DenverChicago
DEN Denver Intl - MDW Chicago Midway
DENMDW
Denver Intl
Sat 10/3
12:30 pm-6:00 pm
1 stop4h 30m
Chicago Midway
Mon 10/5
6:05 am-7:45 am
Nonstop2h 40m
$219
DenverChicago
DEN Denver Intl - MDW Chicago Midway
DENMDW
Denver Intl
Sat 9/19
6:30 am-12:39 pm
1 stop5h 09m
Chicago Midway
Tue 9/22
2:00 pm-8:05 pm
1 stop7h 05m
$233
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Thu 9/17
12:50 am-9:00 am
1 stop7h 10m
Lambert-St Louis
Sat 9/19
6:40 am-1:57 pm
1 stop8h 17m
$233
Quickest round-trip
DenverSt. Louis
DEN Denver Intl - STL Lambert-St Louis
DENSTL
Denver Intl
Wed 9/16
5:32 pm-8:38 pm
Nonstop2h 06m
Lambert-St Louis
Thu 9/17
5:10 am-6:43 am
Nonstop2h 33m
$234
DenverChicago
DEN Denver Intl - MDW Chicago Midway
DENMDW
Denver Intl
Sat 11/7
6:00 am-2:30 pm
2 stops7h 30m
Chicago Midway
Mon 11/9
12:45 pm-4:35 pm
1 stop4h 50m
$234
DenverChicago
DEN Denver Intl - MDW Chicago Midway
DENMDW
Denver Intl
Wed 10/28
10:45 am-4:50 pm
2 stops5h 05m
Chicago Midway
Mon 11/2
10:05 am-1:25 pm
1 stop4h 20m
$234
DenverChicago
DEN Denver Intl - MDW Chicago Midway
DENMDW
Denver Intl
Fri 10/16
11:20 am-5:15 pm
1 stop4h 55m
Chicago Midway
Tue 10/20
1:05 pm-4:30 pm
1 stop4h 25m
$236
DenverChicago
DEN Denver Intl - MDW Chicago Midway
DENMDW
Denver Intl
Fri 11/6
4:10 pm-10:00 pm
1 stop4h 50m
Chicago Midway
Mon 11/9
12:45 pm-4:35 pm
1 stop4h 50m
$240
DenverChicago
DEN Denver Intl - MDW Chicago Midway
DENMDW
Denver Intl
Fri 12/4
6:15 am-1:01 pm
1 stop5h 46m
Chicago Midway
Tue 12/8
9:37 am-3:08 pm
1 stop6h 31m
$245
Showing 1-10 of 60 resultsSorted by cheapest first
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.
DEN-STL
DEN-ORD
DEN-RFD
DEN-PIA
DEN-MLI
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 Denver to Illinois
DEN-USIL
DEN-STL
DEN-ORD
DEN-RFD
DEN-PIA
What is the cheapest month to book a flight from Denver to Illinois?
Currently, January is the cheapest month in which you can book a flight from Denver to Illinois (average of $237). Flying from Denver to Illinois in July is currently the most expensive (average of $345). 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 August 29, 2026.
It’s optimal to fly from Denver to Illinois in the morning. By choosing this option you can save up to 17% on the cost of your flight, compared to a flight at noon.
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 August 29, 2026.
The most flights from DEN to USIL are scheduled on a Friday (72 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (33 on average).
How much does it cost to fly round-trip from Denver to Illinois?
Airfare is below average for this route at the moment.
Denver to Illinois flights typically cost between $186 and $326 in September.The cheapest round-trip price found within the last 5 days was $162 on Frontier (Sep 19-Sep 21).
How far ahead should I book a flight from Denver to Illinois?
To ensure you get the cheapest price possible for a flight from Denver to Illinois, you should look to book at least 78 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.
What is the cheapest day to fly from Denver to Illinois?
Use this chart to determine the cheapest time to fly round-trip from Denver to Illinois. Price data was last updated on August 29, 2026.
Travelers seeking maximum savings on their Denver to Illinois flight should consider departing on Friday at noon when fares are most often at their lowest. Saturday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
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 August 29, 2026.
Read through reviews of airlines operating flights from Denver to Illinois, such as Southwest,United Airlines, andAllegiant Air. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.5
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentAnonymous,Feb 2026
DEN - BDL
Entertainment
7.5
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentAnonymous,Feb 2026
DEN - BDL
Entertainment
7.5
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentAnonymous,Feb 2026
DEN - BDL
Entertainment
7.5
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentAnonymous,Feb 2026
DEN - BDL
Entertainment
7.5
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentAnonymous,Feb 2026
DEN - BDL
Entertainment
7.5
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentAnonymous,Feb 2026
DEN - BDL
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.
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Alternative routes for Denver to Illinois
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Complete your trip
Complete your trip to Illinois by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Denver to Illinois by cabin class
Find flights from Denver to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Denver and Illinois flights
Browse other Denver and Illinois flight options. Last updated on August 29, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Denver to Illinois flights
Consider these flights traveling from Denver to Illinois.
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 7,457,451 searches. Data last updated August 29, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$81 | Average$199 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$91 | Average$224 | FlexibilityNo cancel fee | On-time88% | |
| Cheapest$138 | Average$281 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$170 | Average$329 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$171 | Average$411 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$182 | Average$367 | FlexibilityNo cancel fee | On-time69% |