$118+ Cheap flights from Montana to Illinois
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/16. Fares are subject to change and may not be available on all flights or dates of travel.
BZN — ORD
Oct 20 — Oct 271
Round-trip
1 adult, Economy
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Cheapest flights from Montana to IllinoisExplore the most affordable flight options available from Montana to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 20, 2026.
Explore the most affordable flight options available from Montana to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 20, 2026.
This Southwest deal was found by Cheapflights users on 9/17. 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 10/172:35 pm -
1 stop5h 25m
Sat 10/246:15 am -
1 stop5h 20m
Deal found 9/17![Southwest logo]()
$297
This Alaska Airlines deal was found by Cheapflights users on 9/17. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/177:24 am -
1 stop9h 56m
Sat 10/249:00 am -
1 stop10h 19m
Deal found 9/17![Alaska Airlines logo]()
$319
This United Airlines deal was found by Cheapflights users on 9/17. 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.
Tue 11/32:42 pm -
1 stop7h 04m
Tue 11/105:48 pm -
1 stop5h 42m
Deal found 9/17![United Airlines logo]()
$321
This Delta deal was found by Cheapflights users on 9/17. 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 11/52:29 pm -
1 stop8h 25m
Mon 11/97:08 am -
1 stop5h 57m
Deal found 9/17![Delta logo]()
$323
This Delta deal was found by Cheapflights users on 9/17. 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 11/35:20 am -
2 stops11h 27m
Tue 11/107:35 am -
1 stop5h 43m
Deal found 9/17![Delta logo]()
$326
This United Airlines deal was found by Cheapflights users on 9/19. 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.
Sat 9/1911:43 am -
Nonstop3h 05m
Sat 10/242:30 pm -
1 stop7h 40m
Deal found 9/19![United Airlines logo]()
$327
This Delta deal was found by Cheapflights users on 9/17. 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 11/126:23 pm -
1 stop5h 17m
Mon 11/162:21 pm -
2 stops10h 58m
Deal found 9/17![Delta logo]()
$328
This Kiwi.com deal was found by Cheapflights users on 9/18. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/27:59 pm -
2 stops27h 22m
Thu 11/55:15 pm -
1 stop16h 59m
Deal found 9/18![Multiple Airlines logo]()
$329
This Kiwi.com deal was found by Cheapflights users on 9/17. 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 10/299:56 am -
1 stop18h 17m
Tue 11/38:13 pm -
2 stops37h 53m
Deal found 9/17![Multiple Airlines logo]()
$330
This American Airlines deal was found by Cheapflights users on 9/18. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/231:15 pm -
Nonstop3h 14m
Sun 10/259:58 am -
Nonstop3h 27m
Deal found 9/18![American Airlines logo]()
$339
This United Airlines deal was found by Cheapflights users on 9/17. 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 11/52:37 pm -
1 stop5h 22m
Mon 11/95:00 am -
2 stops9h 30m
Deal found 9/17![United Airlines logo]()
$342
This Southwest deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/212:45 pm -
1 stop7h 30m
Fri 10/236:25 pm -
1 stop6h 00m
Deal found 9/16![Southwest logo]()
$342
Best flights from Montana to IllinoisDiscover carefully curated flight deals from Montana to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 20, 2026.
Discover carefully curated flight deals from Montana to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 20, 2026.
This Southwest deal was found by Cheapflights users on 9/17. 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 10/178:15 am -
2 stops8h 45m
Sat 10/246:15 am -
1 stop5h 20m
Deal found 9/17![Southwest logo]()
$303
This United Airlines deal was found by Cheapflights users on 9/17. 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.
Tue 11/32:42 pm -
1 stop7h 04m
Tue 11/105:48 pm -
1 stop5h 42m
Deal found 9/17![United Airlines logo]()
$321
This Delta deal was found by Cheapflights users on 9/18. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/245:45 am -
2 stops9h 52m
Sat 2/276:00 am -
2 stops7h 19m
Deal found 9/18![Delta logo]()
$331
This Alaska Airlines deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/236:59 pm -
1 stop9h 41m
Sun 10/256:00 am -
1 stop9h 15m
Deal found 9/15![Alaska Airlines logo]()
$335
This United Airlines deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 1/712:50 pm -
Nonstop3h 08m
Sun 1/109:10 am -
Nonstop3h 38m
Deal found 9/16![United Airlines logo]()
$339
This Delta deal was found by Cheapflights users on 9/17. 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 11/61:18 pm -
1 stop7h 47m
Tue 11/102:44 pm -
2 stops9h 02m
Deal found 9/17![Delta logo]()
$354
This Southwest deal was found by Cheapflights users on 9/18. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/294:15 pm -
1 stop7h 05m
Mon 11/25:55 am -
1 stop5h 35m
Deal found 9/18![Southwest logo]()
$359
This United Airlines deal was found by Cheapflights users on 9/17. 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.
Sun 12/204:15 pm -
Nonstop3h 12m
Sun 1/312:45 pm -
Nonstop3h 34m
Deal found 9/17![United Airlines logo]()
$339
This Delta deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/135:30 am -
1 stop5h 55m
Tue 2/169:30 am -
2 stops9h 13m
Deal found 9/16![Delta logo]()
$354
This Southwest deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/188:05 am -
2 stops8h 20m
Sun 11/226:10 am -
1 stop5h 20m
Deal found 9/16![Southwest logo]()
$368
This Alaska Airlines deal was found by Cheapflights users on 9/19. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/136:34 pm -
1 stop10h 06m
Mon 11/166:35 pm -
1 stop18h 40m
Deal found 9/19![Alaska Airlines logo]()
$409
This United Airlines deal was found by Cheapflights users on 9/17. 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 10/292:37 pm -
1 stop7h 09m
Tue 11/39:07 am -
Nonstop3h 38m
Deal found 9/17![United Airlines logo]()
$345
This Delta deal was found by Cheapflights users on 9/20. 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.
Sat 1/92:00 pm -
1 stop7h 10m
Sun 1/176:00 am -
1 stop8h 16m
Deal found 9/20![Delta logo]()
$359
This Alaska Airlines deal was found by Cheapflights users on 9/19. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/277:03 am -
1 stop6h 50m
Thu 10/293:49 pm -
1 stop8h 05m
Deal found 9/19![Alaska Airlines logo]()
$409
This United Airlines deal was found by Cheapflights users on 9/19. 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.
Sat 10/102:37 pm -
1 stop7h 09m
Mon 10/124:45 pm -
Nonstop3h 27m
Deal found 9/19![United Airlines logo]()
$345
This Delta deal was found by Cheapflights users on 9/19. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/106:00 am -
1 stop4h 50m
Fri 11/136:00 am -
1 stop8h 20m
Deal found 9/19![Delta logo]()
$359
This Southwest deal was found by Cheapflights users on 9/17. 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 1/811:30 am -
1 stop6h 00m
Sun 1/106:40 am -
2 stops9h 05m
Deal found 9/17![Southwest logo]()
$407
This Alaska Airlines deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/145:10 pm -
1 stop11h 30m
Wed 11/189:30 am -
1 stop8h 00m
Deal found 9/16![Alaska Airlines logo]()
$410
This Delta deal was found by Cheapflights users on 9/20. 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.
Fri 1/86:00 am -
1 stop4h 51m
Sat 1/166:00 am -
1 stop8h 16m
Deal found 9/20![Delta logo]()
$359
This United Airlines deal was found by Cheapflights users on 9/17. 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 10/1612:26 pm -
Nonstop3h 34m
Mon 10/198:40 am -
Nonstop3h 48m
Deal found 9/17![United Airlines logo]()
$359
This Southwest deal was found by Cheapflights users on 9/18. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/26:15 pm -
1 stop10h 25m
Mon 10/56:25 pm -
1 stop6h 00m
Deal found 9/18![Southwest logo]()
$414
This Delta deal was found by Cheapflights users on 9/20. 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.
Mon 1/112:00 pm -
1 stop7h 10m
Fri 1/155:35 pm -
1 stop7h 23m
Deal found 9/20![Delta logo]()
$359
This United Airlines deal was found by Cheapflights users on 9/17. 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 10/175:12 pm -
1 stop5h 47m
Sat 10/248:40 am -
Nonstop3h 48m
Deal found 9/17![United Airlines logo]()
$369
This Alaska Airlines deal was found by Cheapflights users on 9/19. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/253:49 pm -
1 stop7h 10m
Fri 10/303:49 pm -
1 stop8h 05m
Deal found 9/19![Alaska Airlines logo]()
$458
This Delta deal was found by Cheapflights users on 9/20. 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.
Sun 1/105:45 am -
1 stop5h 40m
Sun 1/177:10 am -
1 stop7h 06m
Deal found 9/20![Delta logo]()
$359
This United Airlines deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/75:12 pm -
1 stop5h 47m
Fri 10/168:40 am -
Nonstop3h 48m
Deal found 9/16![United Airlines logo]()
$369
This Southwest deal was found by Cheapflights users on 9/18. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/26:15 pm -
1 stop10h 25m
Mon 10/193:45 pm -
2 stops8h 40m
Deal found 9/18![Southwest logo]()
$462
This Delta deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/182:30 pm -
1 stop8h 26m
Sun 11/226:13 am -
1 stop7h 01m
Deal found 9/16![Delta logo]()
$363
This Southwest deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/178:15 am -
2 stops8h 45m
Mon 10/193:45 pm -
2 stops8h 40m
Deal found 9/16![Southwest logo]()
$464
This United Airlines deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/142:30 pm -
1 stop8h 29m
Wed 10/218:40 am -
Nonstop3h 48m
Deal found 9/15![United Airlines logo]()
$386
Last-minute flights from Montana to IllinoisDiscover last-minute flight deals from Montana to Illinois. Data last updated September 20, 2026 and is based on user searches.
Discover last-minute flight deals from Montana to Illinois. Data last updated September 20, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 9/19. 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.
Sat 9/1911:43 am -
Nonstop3h 05m
Sat 10/242:30 pm -
1 stop7h 40m
Deal found 9/19![United Airlines logo]()
$327
This United Airlines deal was found by Cheapflights users on 9/19. 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.
Sat 9/1911:43 am -
Nonstop3h 05m
Sun 9/205:00 am -
1 stop5h 41m
Deal found 9/19![United Airlines logo]()
$343
This Southwest deal was found by Cheapflights users on 9/17. 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 10/26:15 pm -
1 stop10h 25m
Tue 10/62:10 pm -
2 stops9h 00m
Deal found 9/17![Southwest logo]()
$348
This United Airlines deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/102:37 pm -
1 stop7h 09m
Sun 10/114:45 pm -
Nonstop3h 27m
Deal found 9/16![United Airlines logo]()
$345
This Southwest deal was found by Cheapflights users on 9/17. 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 10/172:35 pm -
1 stop5h 25m
Sat 10/246:15 am -
1 stop5h 20m
Deal found 9/17![Southwest logo]()
$297
This Alaska Airlines deal was found by Cheapflights users on 9/17. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/177:24 am -
1 stop9h 56m
Sat 10/249:00 am -
1 stop10h 19m
Deal found 9/17![Alaska Airlines logo]()
$319
This United Airlines deal was found by Cheapflights users on 9/19. 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.
Sat 10/172:37 pm -
1 stop7h 09m
Sat 10/244:20 pm -
1 stop6h 02m
Deal found 9/19![United Airlines logo]()
$348
This Southwest deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/212:45 pm -
1 stop7h 30m
Fri 10/236:25 pm -
1 stop6h 00m
Deal found 9/16![Southwest logo]()
$342
This American Airlines deal was found by Cheapflights users on 9/18. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/231:15 pm -
Nonstop3h 14m
Sun 10/259:58 am -
Nonstop3h 27m
Deal found 9/18![American Airlines logo]()
$339
This Kiwi.com deal was found by Cheapflights users on 9/17. 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 10/299:56 am -
1 stop18h 17m
Tue 11/38:13 pm -
2 stops37h 53m
Deal found 9/17![Multiple Airlines logo]()
$330
This United Airlines deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/306:30 am -
1 stop5h 08m
Mon 11/28:00 am -
1 stop8h 16m
Deal found 9/16![United Airlines logo]()
$343
This Delta deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/301:12 pm -
2 stops9h 42m
Mon 11/27:00 am -
1 stop7h 19m
Deal found 9/16![Delta logo]()
$348
One-way flights from Montana to IllinoisSearch for one-way flight options from Montana to Illinois. Find affordable one-way fares based on user searches. Data last updated September 20, 2026.
Search for one-way flight options from Montana to Illinois. Find affordable one-way fares based on user searches. Data last updated September 20, 2026.
This Southwest deal was found by Cheapflights users on 9/17. 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 12/166:45 am -
1 stop6h 25m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/17![Southwest logo]()
$118
This Kiwi.com deal was found by Cheapflights users on 9/17. 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 11/168:18 pm -
1 stop7h 55m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/17![Multiple Airlines logo]()
$122
This Southwest deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/1511:20 am -
1 stop5h 05m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Southwest logo]()
$123
This Kiwi.com deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/211:47 am -
1 stop16h 26m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Multiple Airlines logo]()
$127
This Southwest deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/147:30 am -
2 stops8h 35m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Southwest logo]()
$128
This Kiwi.com deal was found by Cheapflights users on 9/18. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/146:28 pm -
1 stop9h 33m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/18![Multiple Airlines logo]()
$131
This Southwest deal was found by Cheapflights users on 9/17. 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 11/1611:20 am -
1 stop7h 15m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/17![Southwest logo]()
$133
This Kiwi.com deal was found by Cheapflights users on 9/17. 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 11/159:07 pm -
1 stop31h 06m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/17![Multiple Airlines logo]()
$137
This Southwest deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/143:30 pm -
1 stop4h 55m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Southwest logo]()
$139
This Kiwi.com deal was found by Cheapflights users on 9/17. 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 10/510:20 pm -
1 stop30h 18m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/17![Multiple Airlines logo]()
$140
This Kiwi.com deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/1310:14 am -
1 stop24h 32m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/16![Multiple Airlines logo]()
$143
This Kiwi.com deal was found by Cheapflights users on 9/17. 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 11/1612:14 pm -
1 stop15h 59m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/17![Multiple Airlines logo]()
$143
Find flight deals from Montana to Illinois
Keep the following information in mind while searching for Montana to Illinois flight deals. Data was last updated September 20, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $297 (Southwest) |
One-way from | $118 (Southwest) |
Popular in | May |
Cheapest in | January |
Average price | $420 |
Good round-trip deal | $431 or less |
Good one-way deal | $258 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Montana 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 September 20, 2026.
Use the filters below to find and compare flights from Montana to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
BozemanChicago
BZN Bozeman Gallatin Field - ORD Chicago O'Hare Intl
BZNORD
Bozeman Gallatin Field
Fri 10/23
6:59 pm-5:40 am
1 stop9h 41m
Chicago O'Hare Intl
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$160
BozemanChicago
BZN Bozeman Gallatin Field - ORD Chicago O'Hare Intl
BZNORD
Bozeman Gallatin Field
Sun 11/15
6:59 pm-5:40 am
1 stop9h 41m
Chicago O'Hare Intl
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$160
BozemanSt. Louis
BZN Bozeman Gallatin Field - STL Lambert-St Louis
BZNSTL
Bozeman Gallatin Field
Mon 10/26
6:31 pm-12:44 am
1 stop5h 13m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$162
BozemanSt. Louis
BZN Bozeman Gallatin Field - STL Lambert-St Louis
BZNSTL
Bozeman Gallatin Field
Sat 10/17
4:30 pm-11:44 pm
1 stop6h 14m
Lambert-St Louis
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$162
BozemanChicago
BZN Bozeman Gallatin Field - ORD Chicago O'Hare Intl
BZNORD
Bozeman Gallatin Field
Sat 12/12
1:50 pm-11:59 pm
1 stop9h 09m
Chicago O'Hare Intl
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$168
BozemanChicago
BZN Bozeman Gallatin Field - ORD Chicago O'Hare Intl
BZNORD
Bozeman Gallatin Field
Mon 12/14
7:00 am-5:49 pm
1 stop9h 49m
Chicago O'Hare Intl
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$168
BozemanChicago
BZN Bozeman Gallatin Field - ORD Chicago O'Hare Intl
BZNORD
Bozeman Gallatin Field
Fri 12/11
7:14 pm-5:37 am
1 stop9h 23m
Chicago O'Hare Intl
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$168
BillingsChicago
BIL Billings Logan Intl - ORD Chicago O'Hare Intl
BILORD
Billings Logan Intl
Sun 11/15
6:34 am-2:55 pm
1 stop7h 21m
Chicago O'Hare Intl
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$177
BillingsChicago
BIL Billings Logan Intl - ORD Chicago O'Hare Intl
BILORD
Billings Logan Intl
Mon 12/21
2:35 pm-10:42 pm
1 stop7h 07m
Chicago O'Hare Intl
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$177
BillingsChicago
BIL Billings Logan Intl - ORD Chicago O'Hare Intl
BILORD
Billings Logan Intl
Mon 3/15
12:58 pm-9:53 pm
1 stop7h 55m
Chicago O'Hare Intl
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$177
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Montana to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from Montana with our price prediction graph.
BZN-MDW
BZN-ORD
BIL-ORD
BZN-STL
GTF-ORD
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 Montana to Illinois
USMT-USIL
BZN-MDW
BZN-ORD
BIL-ORD
BZN-STL
What is the cheapest month to book a flight from Montana to Illinois?
Currently, January is the cheapest month in which you can book a flight from Montana to Illinois (average of $310). Flying from Montana to Illinois in December is currently the most expensive (average of $463). 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 MT to IL?
Find hourly flight availability from Montana 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 September 20, 2026.
When flying from Montana to Illinois, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
How much does it cost to fly round-trip from Montana to Illinois?
Airfare is typical for this route at the moment.
Montana to Illinois flights typically cost between $303 and $500 in October.The cheapest round-trip price found within the last 5 days was $319 on Alaska Airlines (Oct 17-Oct 24).
How far ahead should I book a flight from Montana to Illinois?
Booking 67 days in advance of your planned departure date is, on average, the best time to get cheap flights from Montana to Illinois. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
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 September 20, 2026.
Get a feel of what it's like to fly with Southwest,Alaska Airlines, andDelta from Montana to Illinois by reading reviews from past customers. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Related info for your journey
Find useful and relevant information for your journey from Montana to Illinois. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Browse thousands of different options on Cheapflights for your next trip
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Alternative routes for Montana to Illinois
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Illinois by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Montana to Illinois by cabin class
Find flights from Montana to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Montana and Illinois flights
Browse other Montana and Illinois flight options. Last updated on September 20, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Find a return flight route from Illinois
Find the right flight back to Montana after your stay in Illinois
Montana to Illinois flights
Consider these flights traveling from Montana to Illinois.
Top 3 airlines flying from Montana to Illinois
Discover the top 3 airlines that operate flights from Montana 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 September 20, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$229 | Average$409 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$230 | Average$473 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$249 | Average$448 | FlexibilityNo cancel fee | On-time69% |