$83+ Cheap flights from Illinois 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 11/6. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — DEN
Oct 2 — Oct 91
Round-trip
1 adult, Economy
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Find cheap flights from Illinois to Denver 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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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 Denver
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Cheapest flights from Illinois to DenverExplore the most affordable flight options available from Illinois to Denver. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 2, 2026.
Explore the most affordable flight options available from Illinois to Denver. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 2, 2026.
This Frontier deal was found by Cheapflights users on 8/31. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/38:10 pm -
Nonstop2h 29m
Fri 10/96:30 am -
1 stop9h 28m
Deal found 8/31![Frontier logo]()
$121
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/215:19 pm -
1 stop15h 33m
Sat 9/264:12 pm -
Nonstop2h 05m
Deal found 8/28![Frontier logo]()
$122
This Expedia deal was found by Cheapflights users on 9/1. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/2412:27 pm -
1 stop27h 33m
Sat 9/264:12 pm -
Nonstop2h 05m
Deal found 9/1![Frontier logo]()
$123
This Cheapflightsfares 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/308:10 pm -
Nonstop2h 29m
Mon 10/54:12 pm -
Nonstop2h 05m
Deal found 8/29![Frontier logo]()
$126
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.
Wed 9/302:29 pm -
2 stops22h 30m
Sat 10/103:54 pm -
Nonstop2h 03m
Deal found 8/29![Frontier logo]()
$127
This Cheapflightsfares deal was found by Cheapflights users on 9/1. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/2612:17 pm -
1 stop12h 27m
Wed 9/304:12 pm -
Nonstop2h 05m
Deal found 9/1![Frontier logo]()
$128
This Cheapflightsfares deal was found by Cheapflights users on 9/1. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/22:29 pm -
1 stop7h 55m
Wed 10/78:50 pm -
Nonstop2h 09m
Deal found 9/1![Frontier logo]()
$129
This Expedia deal was found by Cheapflights users on 9/1. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/2512:17 pm -
1 stop22h 50m
Sat 9/264:12 pm -
Nonstop2h 05m
Deal found 9/1![Frontier logo]()
$131
This Kiwi.com deal was found by Cheapflights users on 8/30. 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 9/232:29 pm -
1 stop7h 34m
Sat 9/264:12 pm -
Nonstop2h 05m
Deal found 8/30![Frontier logo]()
$132
This Cheapflightsfares deal was found by Cheapflights users on 8/30. 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 9/268:10 pm -
Nonstop2h 29m
Mon 9/284:12 pm -
Nonstop2h 05m
Deal found 8/30![Frontier logo]()
$133
This CheapOair deal was found by Cheapflights users on 9/1. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/288:10 pm -
Nonstop2h 29m
Fri 10/26:40 am -
1 stop8h 54m
Deal found 9/1![Frontier logo]()
$134
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/107:42 pm -
Nonstop2h 27m
Sat 10/173:54 pm -
Nonstop2h 03m
Deal found 8/29![Frontier logo]()
$135
Best flights from Illinois to DenverDiscover carefully curated flight deals from Illinois to Denver that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 2, 2026.
Discover carefully curated flight deals from Illinois to Denver that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 2, 2026.
This United Airlines deal was found by Cheapflights users on 9/1. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/35:10 am -
Nonstop2h 33m
Tue 10/68:28 pm -
Nonstop2h 16m
Deal found 9/1![United Airlines logo]()
$177
This Southwest deal was found by Cheapflights users on 9/1. 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.
Thu 9/2410:05 am -
1 stop5h 20m
Mon 9/288:25 pm -
Nonstop2h 25m
Deal found 9/1![Southwest logo]()
$264
This Sun Country Air 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 Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/2110:45 am -
1 stop7h 22m
Mon 12/286:47 pm -
1 stop21h 55m
Deal found 8/28![Sun Country Air logo]()
$295
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/29:29 am -
1 stop6h 38m
Tue 11/106:25 am -
1 stop4h 25m
Deal found 8/29![Delta logo]()
$297
This American Airlines deal was found by Cheapflights users on 8/31. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/275:02 am -
1 stop4h 35m
Sat 10/31:17 pm -
1 stop7h 51m
Deal found 8/31![American Airlines logo]()
$319
This United Airlines deal was found by Cheapflights users on 9/1. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/210:00 pm -
Nonstop2h 54m
Tue 10/63:48 pm -
Nonstop2h 42m
Deal found 9/1![United Airlines logo]()
$245
This Kiwi.com deal was found by Cheapflights users on 8/31. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/194:42 pm -
2 stops40h 33m
Sat 9/266:40 am -
1 stop8h 22m
Deal found 8/31![Multiple Airlines logo]()
$526
This Southwest deal was found by Cheapflights users on 9/1. 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.
Sat 11/215:55 am -
Nonstop2h 50m
Tue 12/14:15 pm -
Nonstop2h 20m
Deal found 9/1![Southwest logo]()
$270
This Southwest deal was found by Cheapflights users on 9/1. 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.
Wed 9/2311:10 am -
1 stop4h 50m
Mon 9/284:40 pm -
1 stop4h 45m
Deal found 9/1![Southwest logo]()
$276
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/202:18 pm -
Nonstop2h 38m
Tue 2/233:00 pm -
Nonstop2h 40m
Deal found 8/29![United Airlines logo]()
$277
This Delta deal was found by Cheapflights users on 8/31. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 1/316:00 am -
1 stop5h 12m
Tue 2/26:45 am -
1 stop4h 52m
Deal found 8/31![Delta logo]()
$305
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/65:00 am -
2 stops10h 21m
Sat 10/106:09 pm -
1 stop4h 50m
Deal found 8/28![American Airlines logo]()
$324
This Sun Country Air 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 Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/287:40 pm -
1 stop22h 42m
Thu 12/317:20 pm -
1 stop14h 28m
Deal found 8/28![Sun Country Air logo]()
$325
This Southwest deal was found by Cheapflights users on 8/31. 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.
Wed 11/48:55 pm -
Nonstop2h 40m
Mon 11/98:40 am -
Nonstop2h 20m
Deal found 8/31![Southwest logo]()
$277
This Delta deal was found by Cheapflights users on 8/30. 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.
Mon 11/166:23 am -
1 stop6h 57m
Sat 11/216:15 am -
1 stop6h 44m
Deal found 8/30![Delta logo]()
$307
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:05 am -
Nonstop2h 40m
Thu 10/225:55 pm -
Nonstop2h 20m
Deal found 8/28![Southwest logo]()
$277
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/282:30 pm -
1 stop8h 18m
Wed 11/45:50 pm -
Nonstop2h 22m
Deal found 8/29![United Airlines logo]()
$309
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/125:02 am -
1 stop7h 33m
Wed 9/166:01 pm -
1 stop5h 02m
Deal found 8/28![American Airlines logo]()
$349
This Delta deal was found by Cheapflights users on 8/30. 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.
Tue 11/36:00 am -
1 stop8h 12m
Tue 11/101:06 pm -
1 stop9h 02m
Deal found 8/30![Delta logo]()
$319
This Southwest deal was found by Cheapflights users on 8/30. 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 10/306:05 am -
Nonstop2h 40m
Mon 11/28:40 am -
Nonstop2h 20m
Deal found 8/30![Southwest logo]()
$279
This United Airlines deal was found by Cheapflights users on 9/1. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/267:50 pm -
Nonstop2h 54m
Mon 9/285:36 pm -
Nonstop2h 42m
Deal found 9/1![United Airlines logo]()
$309
This American Airlines deal was found by Cheapflights users on 9/1. 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.
Sat 9/195:00 am -
1 stop4h 37m
Sat 9/265:30 am -
1 stop7h 40m
Deal found 9/1![American Airlines logo]()
$352
This Southwest deal was found by Cheapflights users on 8/31. 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.
Fri 10/239:20 pm -
Nonstop2h 45m
Mon 10/267:50 am -
Nonstop2h 20m
Deal found 8/31![Southwest logo]()
$279
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/106:48 pm -
1 stop6h 48m
Mon 10/193:14 pm -
1 stop5h 49m
Deal found 8/28![American Airlines logo]()
$355
This Delta deal was found by Cheapflights users on 9/1. 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.
Thu 9/104:32 pm -
1 stop5h 41m
Sat 9/193:00 pm -
1 stop6h 01m
Deal found 9/1![Delta logo]()
$365
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/309:20 pm -
Nonstop3h 00m
Sat 1/28:57 pm -
Nonstop2h 33m
Deal found 8/29![United Airlines logo]()
$336
This Southwest deal was found by Cheapflights users on 8/31. 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.
Fri 10/99:20 pm -
Nonstop2h 45m
Tue 10/1311:00 am -
1 stop4h 05m
Deal found 8/31![Southwest logo]()
$283
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/107:25 pm -
Nonstop2h 45m
Tue 10/1311:00 am -
1 stop4h 05m
Deal found 8/29![Southwest logo]()
$283
This Delta deal was found by Cheapflights users on 9/1. 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.
Sun 9/134:32 pm -
1 stop7h 42m
Sat 9/197:15 am -
1 stop7h 30m
Deal found 9/1![Delta logo]()
$379
This United Airlines deal was found by Cheapflights users on 9/1. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/205:00 am -
1 stop4h 46m
Sun 11/224:48 pm -
1 stop5h 11m
Deal found 9/1![United Airlines logo]()
$358
Last-minute flights from Illinois to DenverDiscover last-minute flight deals from Illinois to Denver. Data last updated September 2, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to Denver. Data last updated September 2, 2026 and is based on user searches.
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/215:19 pm -
1 stop15h 33m
Sat 9/264:12 pm -
Nonstop2h 05m
Deal found 8/28![Frontier logo]()
$122
This Kiwi.com deal was found by Cheapflights users on 8/30. 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 9/232:29 pm -
1 stop7h 34m
Sat 9/264:12 pm -
Nonstop2h 05m
Deal found 8/30![Frontier logo]()
$132
This Expedia deal was found by Cheapflights users on 9/1. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/2412:27 pm -
1 stop27h 33m
Sat 9/264:12 pm -
Nonstop2h 05m
Deal found 9/1![Frontier logo]()
$123
This Expedia deal was found by Cheapflights users on 9/1. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/2512:17 pm -
1 stop22h 50m
Sat 9/264:12 pm -
Nonstop2h 05m
Deal found 9/1![Frontier logo]()
$131
This Cheapflightsfares deal was found by Cheapflights users on 9/1. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/2612:17 pm -
1 stop12h 27m
Wed 9/304:12 pm -
Nonstop2h 05m
Deal found 9/1![Frontier logo]()
$128
This Cheapflightsfares deal was found by Cheapflights users on 8/30. 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 9/268:10 pm -
Nonstop2h 29m
Mon 9/284:12 pm -
Nonstop2h 05m
Deal found 8/30![Frontier logo]()
$133
This Cheapflightsfares 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/288:10 pm -
Nonstop2h 29m
Tue 9/296:38 pm -
1 stop15h 54m
Deal found 8/28![Frontier logo]()
$121
This CheapOair deal was found by Cheapflights users on 9/1. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/288:10 pm -
Nonstop2h 29m
Fri 10/26:40 am -
1 stop8h 54m
Deal found 9/1![Frontier logo]()
$134
This Cheapflightsfares 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/308:10 pm -
Nonstop2h 29m
Mon 10/54:12 pm -
Nonstop2h 05m
Deal found 8/29![Frontier logo]()
$126
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.
Wed 9/302:29 pm -
2 stops22h 30m
Sat 10/103:54 pm -
Nonstop2h 03m
Deal found 8/29![Frontier logo]()
$127
This Cheapflightsfares deal was found by Cheapflights users on 9/1. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/22:29 pm -
1 stop7h 55m
Wed 10/78:50 pm -
Nonstop2h 09m
Deal found 9/1![Frontier logo]()
$129
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/107:42 pm -
Nonstop2h 27m
Sat 10/173:54 pm -
Nonstop2h 03m
Deal found 8/29![Frontier logo]()
$135
One-way flights from Illinois to DenverSearch for one-way flight options from Illinois to Denver. Find affordable one-way fares based on user searches. Data last updated September 2, 2026.
Search for one-way flight options from Illinois to Denver. Find affordable one-way fares based on user searches. Data last updated September 2, 2026.
This Super.com deal was found by Cheapflights users on 8/31. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/67:59 pm -
Nonstop2h 31m
Deal found 8/31![Frontier logo]()
$83
This Kiwi.com deal was found by Cheapflights users on 8/31. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/52:29 pm -
1 stop18h 35m
Deal found 8/31![Frontier logo]()
$84
This Kiwi.com deal was found by Cheapflights users on 8/31. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/282:29 pm -
1 stop18h 35m
Deal found 8/31![Frontier logo]()
$85
This Kiwi.com deal was found by Cheapflights users on 9/1. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/610:07 am -
Nonstop2h 20m
Deal found 9/1![Allegiant Air logo]()
$87
This Frontier deal was found by Cheapflights users on 8/31. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/2512:17 pm -
1 stop7h 16m
Deal found 8/31![Frontier logo]()
$87
This Southwest deal was found by Cheapflights users on 9/1. 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.
Thu 10/19:50 pm -
Nonstop2h 20m
Deal found 9/1![Southwest logo]()
$89
This Kiwi.com deal was found by Cheapflights users on 8/31. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/306:44 pm -
1 stop27h 48m
Deal found 8/31![Frontier logo]()
$90
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 9/2612:17 pm -
1 stop7h 16m
Deal found 8/28![Frontier logo]()
$91
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 9/191:06 pm -
1 stop9h 43m
Deal found 8/28![Frontier logo]()
$92
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.
Fri 10/166:35 pm -
1 stop14h 31m
Deal found 8/28![Frontier logo]()
$92
This Super.com deal was found by Cheapflights users on 8/30. 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.
Wed 9/306:30 am -
Nonstop2h 45m
Deal found 8/30![Frontier logo]()
$92
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.
Thu 10/151:12 pm -
1 stop9h 37m
Deal found 8/28![Frontier logo]()
$93
Find flight deals from Illinois to Denver
Keep the following information in mind while searching for Illinois to Denver flight deals. Data was last updated September 2, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $121 (Frontier) |
One-way from | $83 (Super.com) |
Popular in | July |
Cheapest in | October |
Average price | $242 |
Good round-trip deal | $241 or less |
Good one-way deal | $148 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Illinois 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 7,457,451 searches. Data last updated September 2, 2026.
Use the filters below to find and compare flights from Illinois to Denver that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
Quickest round-trip
St. LouisDenver
STL Lambert-St Louis - DEN Denver Intl
STLDEN
Lambert-St Louis
Sat 10/3
5:10 am-6:43 am
Nonstop2h 33m
Denver Intl
Tue 10/6
8:28 pm-11:44 pm
Nonstop2h 16m
$177
ChicagoDenver
ORD Chicago O'Hare Intl - DEN Denver Intl
ORDDEN
Chicago O'Hare Intl
Fri 10/2
10:00 pm-11:54 pm
Nonstop2h 54m
Denver Intl
Tue 10/6
3:48 pm-7:30 pm
Nonstop2h 42m
$245
ChicagoDenver
MDW Chicago Midway - DEN Denver Intl
MDWDEN
Chicago Midway
Thu 9/24
10:05 am-2:25 pm
1 stop5h 20m
Denver Intl
Mon 9/28
8:25 pm-11:50 pm
Nonstop2h 25m
$264
ChicagoDenver
MDW Chicago Midway - DEN Denver Intl
MDWDEN
Chicago Midway
Sat 11/21
5:55 am-7:45 am
Nonstop2h 50m
Denver Intl
Tue 12/1
4:15 pm-7:35 pm
Nonstop2h 20m
$270
ChicagoDenver
MDW Chicago Midway - DEN Denver Intl
MDWDEN
Chicago Midway
Wed 9/23
11:10 am-3:00 pm
1 stop4h 50m
Denver Intl
Mon 9/28
4:40 pm-10:25 pm
1 stop4h 45m
$276
ChicagoDenver
ORD Chicago O'Hare Intl - DEN Denver Intl
ORDDEN
Chicago O'Hare Intl
Sat 2/20
2:18 pm-3:56 pm
Nonstop2h 38m
Denver Intl
Tue 2/23
3:00 pm-6:40 pm
Nonstop2h 40m
$277
ChicagoDenver
MDW Chicago Midway - DEN Denver Intl
MDWDEN
Chicago Midway
Wed 11/4
8:55 pm-10:35 pm
Nonstop2h 40m
Denver Intl
Mon 11/9
8:40 am-12:00 pm
Nonstop2h 20m
$277
ChicagoDenver
MDW Chicago Midway - DEN Denver Intl
MDWDEN
Chicago Midway
Tue 10/20
6:05 am-7:45 am
Nonstop2h 40m
Denver Intl
Thu 10/22
5:55 pm-9:15 pm
Nonstop2h 20m
$277
ChicagoDenver
MDW Chicago Midway - DEN Denver Intl
MDWDEN
Chicago Midway
Fri 10/30
6:05 am-7:45 am
Nonstop2h 40m
Denver Intl
Mon 11/2
8:40 am-12:00 pm
Nonstop2h 20m
$279
ChicagoDenver
MDW Chicago Midway - DEN Denver Intl
MDWDEN
Chicago Midway
Fri 10/23
9:20 pm-11:05 pm
Nonstop2h 45m
Denver Intl
Mon 10/26
7:50 am-11:10 am
Nonstop2h 20m
$279
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Illinois to Denver
Have a flexible travel schedule? Discover the best time to fly to Denver from Illinois with our price prediction graph.
STL-DEN
PIA-DEN
MDW-DEN
ORD-DEN
BMI-DEN
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 Illinois to Denver
USIL-DEN
STL-DEN
PIA-DEN
MDW-DEN
ORD-DEN
What is the cheapest month to book a flight from Illinois to Denver?
Currently, January is the cheapest month in which you can book a flight from Illinois to Denver (average of $225). Flying from Illinois to Denver in June is currently the most expensive (average of $323). 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 DEN?
Find hourly flight availability from Illinois 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 September 2, 2026.
A simple way to save on the total cost of your ticket is to fly from Illinois to Denver in the evening. If you’re flexible enough to do this you can expect to save up to 30% on your trip compared to booking a flight in the morning.
Weekly flight availability from Illinois to Denver
Explore weekly flight availability from Illinois 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 September 2, 2026.
The most flights from USIL to DEN are scheduled on a Monday (62 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (34 on average).
How much does it cost to fly round-trip from Illinois to Denver?
Airfare is below average for this route at the moment.
Illinois to Denver flights typically cost between $173 and $323 in September.The cheapest round-trip price found within the last 5 days was $155 on Frontier (Sep 23-Sep 26).
How far ahead should I book a flight from Illinois to Denver?
To ensure you get the cheapest price possible for a flight from Illinois to Denver, you should look to book at least 84 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 Illinois to Denver?
Use this chart to determine the cheapest time to fly round-trip from Illinois to Denver. Price data was last updated on August 29, 2026.
Travelers seeking maximum savings on their Illinois to Denver flight should consider departing on Monday at noon when fares are most often at their lowest. Monday mornings flights should be avoided if possible as fares are typically the most expensive at this time.
Related info for your journey
Find useful and relevant information for your journey from Illinois to Denver. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near Denver?
Book flights to Denver if you plan to visit one of these locationsThornton
Westminster
Lakewood
Black Hawk
Centennial
Broomfield
Golden
Wheat Ridge
Silverthorne
Central City
Fort Morgan
Greeley
Cripple Creek
Winter Park
Limon
Manitou Springs
Frisco
Englewood
Glendale
Evergreen
Browse thousands of different options on Cheapflights for your next trip
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Alternative routes for Illinois to Denver
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Complete your trip
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Other flights to Denver
Explore flights to Denver departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on September 2, 2026.
Search flights from Illinois to Denver by cabin class
Find flights from Illinois to Denver, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Illinois and Denver flights
Browse other Illinois and Denver flight options. Last updated on September 2, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Illinois to Denver flights
Consider these flights traveling from Illinois to Denver.
Top 7 airlines flying from Illinois to Denver
Discover the top 7 airlines that operate flights from Illinois 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 7,457,451 searches. Data last updated September 2, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$71 | Average$184 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$74 | Average$283 | FlexibilityNo cancel fee | On-time88% | |
| Cheapest$105 | Average$284 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$145 | Average$223 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$151 | Average$309 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$156 | Average$389 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$171 | Average$379 | FlexibilityNo cancel fee | On-time69% |