$70+ Cheap flights from St. Louis (STL) 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 11/11. Fares are subject to change and may not be available on all flights or dates of travel.
STL — ORD
Nov 19 — Nov 261
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis 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 St. Louis to IllinoisExplore the most affordable flight options available from St. Louis to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 20, 2026.
Explore the most affordable flight options available from St. Louis to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 20, 2026.
This Southwest deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/123:55 pm -
1 stop6h 25m
Sun 11/158:45 am -
Nonstop1h 20m
Deal found 10/19![Southwest logo]()
$153
This Kiwi.com deal was found by Cheapflights users on 10/15. 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.
Thu 11/1212:14 pm -
1 stop7h 01m
Thu 11/197:31 am -
1 stop11h 08m
Deal found 10/15![Frontier logo]()
$157
This Priceline deal was found by Cheapflights users on 10/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/197:24 pm -
1 stop4h 49m
Mon 11/237:49 am -
1 stop9h 51m
Deal found 10/15![Frontier logo]()
$159
This Frontier deal was found by Cheapflights users on 10/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/186:34 pm -
1 stop5h 13m
Mon 11/239:09 am -
1 stop8h 31m
Deal found 10/15![Frontier logo]()
$162
This Frontier deal was found by Cheapflights users on 10/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/184:18 pm -
1 stop8h 03m
Mon 11/237:49 am -
1 stop9h 51m
Deal found 10/15![Frontier logo]()
$162
This Southwest deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1110:30 am -
1 stop5h 45m
Fri 11/132:10 pm -
1 stop6h 15m
Deal found 10/19![Southwest logo]()
$163
This Expedia deal was found by Cheapflights users on 10/16. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/184:18 pm -
1 stop8h 03m
Thu 11/197:31 am -
1 stop11h 08m
Deal found 10/16![Frontier logo]()
$169
This Southwest deal was found by Cheapflights users on 10/16. 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 11/219:50 pm -
Nonstop1h 10m
Sun 11/226:30 am -
Nonstop1h 15m
Deal found 10/16![Southwest logo]()
$171
This American Airlines deal was found by Cheapflights users on 10/15. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/218:12 pm -
Nonstop1h 36m
Sun 11/226:40 pm -
Nonstop1h 24m
Deal found 10/15![American Airlines logo]()
$171
This American Airlines deal was found by Cheapflights users on 10/16. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/196:00 am -
Nonstop1h 36m
Sun 11/226:40 pm -
Nonstop1h 24m
Deal found 10/16![American Airlines logo]()
$181
This American Airlines deal was found by Cheapflights users on 10/16. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/145:16 pm -
Nonstop1h 43m
Sat 11/219:20 am -
Nonstop1h 24m
Deal found 10/16![American Airlines logo]()
$182
This Southwest deal was found by Cheapflights users on 10/15. 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 12/148:25 pm -
Nonstop1h 05m
Mon 1/111:45 pm -
Nonstop1h 15m
Deal found 10/15![Southwest logo]()
$191
Best flights from St. Louis to IllinoisDiscover carefully curated flight deals from St. Louis to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 20, 2026.
Discover carefully curated flight deals from St. Louis to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 20, 2026.
This Southwest deal was found by Cheapflights users on 10/16. 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 11/219:50 pm -
Nonstop1h 10m
Sun 11/226:30 am -
Nonstop1h 15m
Deal found 10/16![Southwest logo]()
$171
This United Airlines deal was found by Cheapflights users on 10/15. 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.
Sun 11/2210:53 am -
Nonstop1h 36m
Sun 11/224:35 pm -
Nonstop1h 34m
Deal found 10/15![United Airlines logo]()
$171
This Delta deal was found by Cheapflights users on 10/16. 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 11/215:30 pm -
1 stop4h 03m
Sun 11/226:23 am -
1 stop5h 58m
Deal found 10/16![Delta logo]()
$191
This American Airlines deal was found by Cheapflights users on 10/16. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/225:02 am -
1 stop5h 53m
Wed 11/255:11 pm -
1 stop5h 03m
Deal found 10/16![American Airlines logo]()
$309
This Southwest deal was found by Cheapflights users on 10/16. 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 12/26:20 am -
Nonstop1h 05m
Thu 12/37:35 am -
Nonstop1h 15m
Deal found 10/16![Southwest logo]()
$191
This Delta deal was found by Cheapflights users on 10/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/179:45 am -
1 stop6h 54m
Mon 11/2312:30 pm -
1 stop4h 01m
Deal found 10/15![Delta logo]()
$201
This Delta deal was found by Cheapflights users on 10/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1810:20 am -
1 stop3h 39m
Sun 11/227:05 am -
1 stop6h 18m
Deal found 10/15![Delta logo]()
$201
This Southwest deal was found by Cheapflights users on 10/15. 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 12/143:00 pm -
1 stop4h 50m
Thu 1/71:50 pm -
1 stop4h 20m
Deal found 10/15![Southwest logo]()
$211
This Delta deal was found by Cheapflights users on 10/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1710:20 am -
1 stop3h 39m
Sun 11/226:23 am -
1 stop5h 58m
Deal found 10/15![Delta logo]()
$201
This United Airlines deal was found by Cheapflights users on 10/15. 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.
Fri 12/45:25 am -
Nonstop1h 33m
Sat 12/52:48 pm -
Nonstop1h 36m
Deal found 10/15![United Airlines logo]()
$281
This Southwest deal was found by Cheapflights users on 10/15. 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.
Fri 11/139:35 pm -
Nonstop1h 10m
Sun 11/158:45 am -
Nonstop1h 20m
Deal found 10/15![Southwest logo]()
$245
This Southwest deal was found by Cheapflights users on 10/15. 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.
Thu 11/55:45 am -
Nonstop1h 10m
Sun 11/86:30 am -
Nonstop1h 15m
Deal found 10/15![Southwest logo]()
$245
This United Airlines deal was found by Cheapflights users on 10/19. 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.
Sun 11/295:00 am -
Nonstop1h 36m
Tue 12/110:52 am -
Nonstop1h 30m
Deal found 10/19![United Airlines logo]()
$312
This Delta deal was found by Cheapflights users on 10/16. 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.
Sun 11/86:47 am -
1 stop6h 12m
Wed 11/112:44 pm -
1 stop5h 45m
Deal found 10/16![Delta logo]()
$265
This Southwest deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/198:25 pm -
Nonstop1h 10m
Mon 11/236:30 am -
Nonstop1h 15m
Deal found 10/19![Southwest logo]()
$257
This Delta deal was found by Cheapflights users on 10/19. 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.
Mon 11/2312:28 pm -
1 stop4h 11m
Tue 11/2410:34 am -
1 stop5h 57m
Deal found 10/19![Delta logo]()
$275
This Delta deal was found by Cheapflights users on 10/19. 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 11/179:45 am -
1 stop6h 56m
Tue 11/246:23 am -
1 stop5h 58m
Deal found 10/19![Delta logo]()
$275
This United Airlines deal was found by Cheapflights users on 10/18. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/76:30 am -
Nonstop1h 27m
Sun 12/139:45 pm -
Nonstop1h 14m
Deal found 10/18![United Airlines logo]()
$407
This Southwest deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/2910:50 pm -
Nonstop1h 05m
Tue 12/18:10 am -
1 stop5h 10m
Deal found 10/19![Southwest logo]()
$315
This United Airlines deal was found by Cheapflights users on 10/19. 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.
Sun 11/155:00 am -
Nonstop1h 36m
Mon 11/164:35 pm -
Nonstop1h 34m
Deal found 10/19![United Airlines logo]()
$429
This United Airlines deal was found by Cheapflights users on 10/16. 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.
Sun 11/16:50 pm -
1 stop4h 09m
Thu 11/55:00 am -
1 stop3h 55m
Deal found 10/16![United Airlines logo]()
$637
This United Airlines deal was found by Cheapflights users on 10/16. 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.
Sun 11/228:50 am -
2 stops14h 09m
Wed 11/258:13 am -
1 stop24h 42m
Deal found 10/16![United Airlines logo]()
$1,059
This United Airlines deal was found by Cheapflights users on 10/15. 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.
Fri 10/306:50 pm -
1 stop4h 09m
Tue 11/38:13 am -
2 stops12h 46m
Deal found 10/15![United Airlines logo]()
$1,072
Last-minute flights from St. Louis to IllinoisDiscover last-minute flight deals from St. Louis to Illinois. Data last updated October 20, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Illinois. Data last updated October 20, 2026 and is based on user searches.
This Southwest deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1110:30 am -
1 stop5h 45m
Fri 11/132:10 pm -
1 stop6h 15m
Deal found 10/19![Southwest logo]()
$163
This Southwest deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/123:55 pm -
1 stop6h 25m
Sun 11/158:45 am -
Nonstop1h 20m
Deal found 10/19![Southwest logo]()
$153
This Kiwi.com deal was found by Cheapflights users on 10/15. 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.
Thu 11/1212:14 pm -
1 stop7h 01m
Thu 11/197:31 am -
1 stop11h 08m
Deal found 10/15![Frontier logo]()
$157
This American Airlines deal was found by Cheapflights users on 10/16. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/145:16 pm -
Nonstop1h 43m
Sat 11/219:20 am -
Nonstop1h 24m
Deal found 10/16![American Airlines logo]()
$182
This Southwest deal was found by Cheapflights users on 10/16. 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 11/145:45 am -
Nonstop1h 10m
Sat 11/146:15 pm -
Nonstop1h 25m
Deal found 10/16![Southwest logo]()
$191
This Frontier deal was found by Cheapflights users on 10/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/186:34 pm -
1 stop5h 13m
Mon 11/239:09 am -
1 stop8h 31m
Deal found 10/15![Frontier logo]()
$162
This Frontier deal was found by Cheapflights users on 10/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/184:18 pm -
1 stop8h 03m
Sun 11/225:12 pm -
1 stop6h 47m
Deal found 10/15![Frontier logo]()
$162
This Expedia deal was found by Cheapflights users on 10/16. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/184:18 pm -
1 stop8h 03m
Thu 11/197:31 am -
1 stop11h 08m
Deal found 10/16![Frontier logo]()
$169
This Priceline deal was found by Cheapflights users on 10/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/197:24 pm -
1 stop4h 49m
Mon 11/237:49 am -
1 stop9h 51m
Deal found 10/15![Frontier logo]()
$159
This American Airlines deal was found by Cheapflights users on 10/16. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/196:00 am -
Nonstop1h 36m
Sun 11/226:40 pm -
Nonstop1h 24m
Deal found 10/16![American Airlines logo]()
$181
This Southwest deal was found by Cheapflights users on 10/16. 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 11/219:50 pm -
Nonstop1h 10m
Sun 11/226:30 am -
Nonstop1h 15m
Deal found 10/16![Southwest logo]()
$171
This American Airlines deal was found by Cheapflights users on 10/15. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/218:12 pm -
Nonstop1h 36m
Sun 11/226:40 pm -
Nonstop1h 24m
Deal found 10/15![American Airlines logo]()
$171
One-way flights from St. Louis to IllinoisSearch for one-way flight options from St. Louis to Illinois. Find affordable one-way fares based on user searches. Data last updated October 20, 2026.
Search for one-way flight options from St. Louis to Illinois. Find affordable one-way fares based on user searches. Data last updated October 20, 2026.
This Kiwi.com deal was found by Cheapflights users on 10/15. 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.
Wed 11/116:34 pm -
1 stop5h 13m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/15![Frontier logo]()
$70
This Southwest deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/139:35 pm -
Nonstop1h 10m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/19![Southwest logo]()
$72
This Frontier deal was found by Cheapflights users on 10/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/216:05 pm -
1 stop6h 38m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/15![Frontier logo]()
$76
This Priceline deal was found by Cheapflights users on 10/16. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/96:34 pm -
1 stop5h 13m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/16![Frontier logo]()
$86
This Frontier deal was found by Cheapflights users on 10/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/512:14 pm -
1 stop7h 01m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/15![Frontier logo]()
$86
This Frontier deal was found by Cheapflights users on 10/19. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/16:13 pm -
1 stop6h 46m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/19![Frontier logo]()
$89
This Super.com deal was found by Cheapflights users on 10/16. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/137:59 pm -
1 stop28h 22m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/16![Frontier logo]()
$91
This Expedia deal was found by Cheapflights users on 10/16. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/97:59 pm -
1 stop28h 22m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/16![Frontier logo]()
$92
This Trip.com deal was found by Cheapflights users on 10/17. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/166:34 pm -
1 stop5h 13m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/17![Frontier logo]()
$93
This Southwest deal was found by Cheapflights users on 10/16. 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.
Mon 11/95:45 am -
Nonstop1h 10m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/16![Southwest logo]()
$96
This American Airlines deal was found by Cheapflights users on 10/16. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/97:26 am -
Nonstop1h 34m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/16![American Airlines logo]()
$96
This Southwest deal was found by Cheapflights users on 10/15. 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.
Thu 11/55:10 pm -
1 stop6h 05m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/15![Southwest logo]()
$106
Find flight deals from St. Louis to Illinois
Keep the following information in mind while searching for St. Louis to Illinois flight deals. Data was last updated October 20, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $153 (Southwest) |
One-way from | $70 (Kiwi.com) |
Popular in | January |
Cheapest in | November |
Average price | $350 |
Good round-trip deal | $268 or less |
Good one-way deal | $182 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from St. Louis 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 October 20, 2026.
Use the filters below to find and compare flights from St. Louis to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisChicago
STL Lambert-St Louis - MDW Chicago Midway
STLMDW
Lambert-St Louis
Tue 12/1
10:15 am-2:35 pm
1 stop4h 20m
Chicago Midway
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$82
St. LouisChicago
STL Lambert-St Louis - ORD Chicago O'Hare Intl
STLORD
Lambert-St Louis
Thu 11/5
7:30 am-9:00 am
Nonstop1h 30m
Chicago O'Hare Intl
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$96
St. LouisChicago
STL Lambert-St Louis - MDW Chicago Midway
STLMDW
Lambert-St Louis
Sat 1/30
5:30 am-6:40 am
Nonstop1h 10m
Chicago Midway
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$96
St. LouisChicago
STL Lambert-St Louis - ORD Chicago O'Hare Intl
STLORD
Lambert-St Louis
Sat 11/14
6:50 pm-8:19 pm
Nonstop1h 29m
Chicago O'Hare Intl
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$96
St. LouisChicago
STL Lambert-St Louis - MDW Chicago Midway
STLMDW
Lambert-St Louis
Thu 11/5
9:35 pm-10:45 pm
Nonstop1h 10m
Chicago Midway
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$96
St. LouisChicago
STL Lambert-St Louis - ORD Chicago O'Hare Intl
STLORD
Lambert-St Louis
Mon 2/22
1:08 pm-2:35 pm
Nonstop1h 27m
Chicago O'Hare Intl
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$96
Quickest round-trip
St. LouisChicago
STL Lambert-St Louis - MDW Chicago Midway
STLMDW
Lambert-St Louis
Sat 11/14
4:20 pm-5:25 pm
Nonstop1h 05m
Chicago Midway
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$96
St. LouisChicago
STL Lambert-St Louis - MDW Chicago Midway
STLMDW
Lambert-St Louis
Sat 11/14
6:40 am-12:51 pm
1 stop6h 11m
Chicago Midway
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$106
St. LouisChicago
STL Lambert-St Louis - ORD Chicago O'Hare Intl
STLORD
Lambert-St Louis
Wed 2/24
6:45 am-12:37 pm
1 stop5h 52m
Chicago O'Hare Intl
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$106
St. LouisChicago
STL Lambert-St Louis - ORD Chicago O'Hare Intl
STLORD
Lambert-St Louis
Mon 2/22
6:45 am-12:37 pm
1 stop5h 52m
Chicago O'Hare Intl
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$106
Showing 1-10 of 43 resultsSorted by cheapest first
Best time to book a flight from St. Louis to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from St. Louis with our price prediction graph.
STL-MDW
STL-ORD
STL-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 St. Louis to Illinois
STL-USIL
STL-MDW
STL-ORD
STL-MLI
What is the cheapest month to book a flight from St. Louis to Illinois?
Currently, November is the cheapest month in which you can book a flight from St. Louis to Illinois (average of $296). Flying from St. Louis to Illinois in January is currently the most expensive (average of $468). 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 STL to IL?
Find hourly flight availability from St. Louis 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 October 20, 2026.
When flying from St. Louis to Illinois, the time of day you fly usually plays a role in the price. Save by searching for a flight in the morning, which can drop the price by up to 32% versus a flight at noon.
Weekly flight availability from St. Louis to Illinois
Explore weekly flight availability from St. Louis 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 October 20, 2026.
The most flights from STL to USIL are scheduled on a Sunday (65 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (50 on average).
How much does it cost to fly round-trip from St. Louis to Illinois?
Airfare is below average for this route at the moment.
St. Louis to Illinois flights typically cost between $284 and $507 in November.The cheapest round-trip price found within the last 5 days was $157 on Frontier (Nov 12-Nov 19).
How far ahead should I book a flight from St. Louis to Illinois?
The best time to book flights from St. Louis to Illinois is 87 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.
What is the cheapest day to fly from St. Louis to Illinois?
Use this chart to determine the cheapest time to fly round-trip from St. Louis to Illinois. Price data was last updated on October 17, 2026.
Travelers seeking maximum savings on their St. Louis to Illinois flight should consider departing on Monday at noon when fares are most often at their lowest. Tuesday evenings 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 October 20, 2026.
See what other customers who have flown with Southwest,United Airlines, andAmerican Airlines from St. Louis to Illinois have to say. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Boarding
8.1
Food
7.0
Comfort
8.0
Crew
8.6
Entertainment
7.4
Overall
7.9
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Boarding
8.1
Food
7.0
Comfort
8.0
Crew
8.6
Entertainment
7.4
Overall
7.9
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Boarding
8.1
Food
7.0
Comfort
8.0
Crew
8.6
Entertainment
7.4
Overall
7.9
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Boarding
8.1
Food
7.0
Comfort
8.0
Crew
8.6
Entertainment
7.4
Overall
7.9
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Related info for your journey
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Alternative routes for St. Louis to Illinois
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Complete your trip
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St. Louis and Illinois flights
Browse other St. Louis and Illinois flight options. Last updated on October 20, 2026.
Popular flight searches
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St. Louis to Illinois flights
Consider these flights traveling from St. Louis to Illinois.
Top 3 airlines flying from St. Louis to Illinois
Discover the top 3 airlines that operate flights from St. Louis 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 October 20, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$117 | Average$324 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$187 | Average$446 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$187 | Average$441 | FlexibilityNo cancel fee | On-time69% |