$49+ Cheap flights from St. Louis (STL) to Illinois
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 5/19. Fares are subject to change and may not be available on all flights or dates of travel.
STL — ORD
Mar 15 — Mar 221
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 February 13, 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 February 13, 2026.
This Delta deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/56:35 am
STL
- MDW
1 stop6h 11m
Delta
Mon 3/91:10 pm
MDW
- STL
1 stop3h 22m
Delta
Deal found 2/11![Delta logo]()
$191
This Delta deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/56:47 pm
STL
- ORD
1 stop5h 09m
Delta
Mon 3/95:59 pm
ORD
- STL
1 stop5h 59m
Delta
Deal found 2/10![Delta logo]()
$191
This Kiwi.com deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/33:49 pm
STL
- MDW
2 stops27h 18m
Frontier
Fri 3/66:05 am
MDW
- STL
1 stop5h 44m
Frontier
Deal found 2/11![Frontier logo]()
$193
This Kiwi.com deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 4/178:13 pm
STL
- ORD
1 stop18h 07m
Multiple Airlines
Wed 4/221:40 pm
ORD
- STL
1 stop20h 50m
Multiple Airlines
Deal found 2/11![Multiple Airlines logo]()
$193
This Southwest deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/315:40 am
STL
- MDW
Nonstop1h 10m
Southwest
Thu 4/211:15 am
MDW
- STL
Nonstop1h 15m
Southwest
Deal found 2/11![Southwest logo]()
$194
This American Airlines deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/78:00 am
STL
- ORD
Nonstop1h 31m
American Airlines
Sun 3/87:15 am
ORD
- STL
Nonstop1h 23m
American Airlines
Deal found 2/11![American Airlines logo]()
$194
This Southwest deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/51:40 pm
STL
- MDW
2 stops6h 30m
Southwest
Mon 3/93:55 pm
MDW
- STL
1 stop5h 00m
Southwest
Deal found 2/10![Southwest logo]()
$196
This Delta deal was found by Cheapflights users on 2/12. Clicking the “Pick Dates” 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 5/23:25 pm
STL
- ORD
1 stop4h 23m
Delta
Mon 5/41:36 pm
ORD
- STL
2 stops9h 37m
Delta
Deal found 2/12![Delta logo]()
$196
This Delta deal was found by Cheapflights users on 2/9. Clicking the “Pick Dates” 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 4/226:20 am
STL
- MDW
2 stops6h 23m
Delta
Fri 4/247:16 pm
MDW
- STL
1 stop3h 57m
Delta
Deal found 2/9![Delta logo]()
$199
This Southwest deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/176:15 am
STL
- MDW
2 stops6h 40m
Southwest
Wed 3/1812:00 pm
MDW
- STL
1 stop5h 55m
Southwest
Deal found 2/10![Southwest logo]()
$202
This Kiwi.com deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/94:51 pm
STL
- MDW
2 stops20h 11m
Multiple Airlines
Wed 3/1111:19 am
MDW
- STL
1 stop12h 00m
Multiple Airlines
Deal found 2/10![Multiple Airlines logo]()
$203
This Kiwi.com deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/61:09 pm
STL
- ORD
1 stop9h 30m
Frontier
Sun 3/87:00 am
ORD
- STL
1 stop15h 02m
Frontier
Deal found 2/11![Frontier logo]()
$203
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 February 13, 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 February 13, 2026.
This Delta deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/56:35 am
STL
- MDW
1 stop6h 11m
Delta
Mon 3/91:10 pm
MDW
- STL
1 stop3h 22m
Delta
Deal found 2/11![Delta logo]()
$191
This Southwest deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/77:35 am
STL
- ORD
1 stop5h 15m
Southwest
Mon 3/94:15 pm
ORD
- STL
1 stop5h 55m
Southwest
Deal found 2/11![Southwest logo]()
$191
This American Airlines deal was found by Cheapflights users on 2/12. Clicking the “Pick Dates” 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 5/22:12 pm
STL
- ORD
1 stop5h 10m
American Airlines
Mon 5/410:30 pm
ORD
- STL
Nonstop1h 16m
American Airlines
Deal found 2/12![American Airlines logo]()
$211
This CheapOair deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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.
Wed 2/253:49 pm
STL
- ORD
1 stop18h 57m
Frontier
Fri 2/273:11 pm
ORD
- STL
1 stop9h 16m
Frontier
Deal found 2/11![Frontier logo]()
$213
This United Airlines deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/57:41 am
STL
- ORD
Nonstop1h 29m
United Airlines
Mon 3/97:42 pm
ORD
- STL
Nonstop1h 25m
United Airlines
Deal found 2/10![United Airlines logo]()
$231
This Delta deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/2812:28 pm
STL
- MDW
1 stop6h 12m
Delta
Sat 4/49:30 am
MDW
- STL
1 stop4h 54m
Delta
Deal found 2/10![Delta logo]()
$191
This Southwest deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/75:45 pm
STL
- MDW
2 stops7h 05m
Southwest
Mon 3/97:00 pm
MDW
- STL
1 stop5h 05m
Southwest
Deal found 2/11![Southwest logo]()
$196
This Delta deal was found by Cheapflights users on 2/12. Clicking the “Pick Dates” 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 5/212:23 pm
STL
- MDW
1 stop6h 13m
Delta
Mon 5/47:16 pm
MDW
- STL
1 stop3h 57m
Delta
Deal found 2/12![Delta logo]()
$191
This Southwest deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/176:15 am
STL
- MDW
2 stops6h 40m
Southwest
Wed 3/1811:30 am
MDW
- STL
1 stop5h 30m
Southwest
Deal found 2/11![Southwest logo]()
$202
This Delta deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 4/46:32 am
STL
- MDW
1 stop5h 57m
Delta
Sat 4/47:20 pm
MDW
- STL
1 stop4h 05m
Delta
Deal found 2/11![Delta logo]()
$191
This Southwest deal was found by Cheapflights users on 2/9. Clicking the “Pick Dates” 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 4/221:45 pm
STL
- MDW
Nonstop1h 10m
Southwest
Fri 4/247:50 am
MDW
- STL
Nonstop1h 15m
Southwest
Deal found 2/9![Southwest logo]()
$207
This Delta deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/2810:50 am
STL
- ORD
1 stop5h 28m
Delta
Sat 4/49:35 am
ORD
- STL
1 stop4h 49m
Delta
Deal found 2/10![Delta logo]()
$191
This Southwest deal was found by Cheapflights users on 2/12. Clicking the “Pick Dates” 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 4/179:40 pm
STL
- MDW
Nonstop1h 05m
Southwest
Wed 4/228:55 pm
MDW
- STL
Nonstop1h 15m
Southwest
Deal found 2/12![Southwest logo]()
$207
This Delta deal was found by Cheapflights users on 2/12. Clicking the “Pick Dates” 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 3/56:35 am
STL
- ORD
1 stop6h 45m
Delta
Mon 3/95:59 pm
ORD
- STL
1 stop5h 59m
Delta
Deal found 2/12![Delta logo]()
$191
This Delta deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 4/46:32 am
STL
- ORD
1 stop6h 52m
Delta
Sat 4/45:59 pm
ORD
- STL
1 stop5h 59m
Delta
Deal found 2/11![Delta logo]()
$191
This Southwest deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/266:15 am
STL
- ORD
1 stop8h 50m
Southwest
Tue 3/314:15 pm
ORD
- STL
1 stop5h 10m
Southwest
Deal found 2/10![Southwest logo]()
$214
This Delta deal was found by Cheapflights users on 2/12. Clicking the “Pick Dates” 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 5/23:25 pm
STL
- ORD
1 stop4h 23m
Delta
Mon 5/41:36 pm
ORD
- STL
2 stops9h 37m
Delta
Deal found 2/12![Delta logo]()
$196
This Southwest deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/103:30 pm
STL
- MDW
1 stop4h 10m
Southwest
Mon 8/319:20 am
MDW
- STL
Nonstop1h 10m
Southwest
Deal found 2/11![Southwest logo]()
$217
This Southwest deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/106:20 am
STL
- ORD
1 stop7h 35m
Southwest
Mon 8/314:00 pm
ORD
- STL
1 stop6h 05m
Southwest
Deal found 2/11![Southwest logo]()
$227
This Delta deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/173:05 pm
STL
- ORD
1 stop6h 21m
Delta
Tue 3/247:10 am
ORD
- STL
2 stops9h 55m
Delta
Deal found 2/10![Delta logo]()
$213
This United Airlines deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 2/259:55 am
STL
- DEC
1 stop22h 57m
United Airlines
Sun 3/17:15 pm
DEC
- STL
1 stop3h 44m
United Airlines
Deal found 2/10![United Airlines logo]()
$454
Last-minute flights from St. Louis to IllinoisDiscover last-minute flight deals from St. Louis to Illinois. Data last updated February 13, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Illinois. Data last updated February 13, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/33:49 pm
STL
- MDW
2 stops27h 18m
Frontier
Fri 3/66:05 am
MDW
- STL
1 stop5h 44m
Frontier
Deal found 2/11![Frontier logo]()
$193
This Kiwi.com deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/33:49 pm
STL
- ORD
1 stop24h 03m
Frontier
Fri 3/65:05 am
ORD
- STL
1 stop6h 44m
Frontier
Deal found 2/11![Frontier logo]()
$208
This Delta deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/56:35 am
STL
- MDW
1 stop6h 11m
Delta
Mon 3/91:10 pm
MDW
- STL
1 stop3h 22m
Delta
Deal found 2/11![Delta logo]()
$191
This Delta deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/56:47 pm
STL
- ORD
1 stop5h 09m
Delta
Mon 3/95:59 pm
ORD
- STL
1 stop5h 59m
Delta
Deal found 2/10![Delta logo]()
$191
This Southwest deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/51:40 pm
STL
- MDW
2 stops6h 30m
Southwest
Mon 3/93:55 pm
MDW
- STL
1 stop5h 00m
Southwest
Deal found 2/10![Southwest logo]()
$196
This Kiwi.com deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/61:09 pm
STL
- ORD
1 stop9h 30m
Frontier
Sun 3/87:00 am
ORD
- STL
1 stop15h 02m
Frontier
Deal found 2/11![Frontier logo]()
$203
This American Airlines deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/78:00 am
STL
- ORD
Nonstop1h 31m
American Airlines
Sun 3/87:15 am
ORD
- STL
Nonstop1h 23m
American Airlines
Deal found 2/11![American Airlines logo]()
$194
This Kiwi.com deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/94:51 pm
STL
- MDW
2 stops20h 11m
Multiple Airlines
Wed 3/1111:19 am
MDW
- STL
1 stop12h 00m
Multiple Airlines
Deal found 2/10![Multiple Airlines logo]()
$203
This Southwest deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/108:50 pm
STL
- MDW
Nonstop1h 05m
Southwest
Mon 8/313:10 pm
MDW
- STL
Nonstop1h 10m
Southwest
Deal found 2/11![Southwest logo]()
$207
This American Airlines deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/108:00 am
STL
- ORD
Nonstop1h 31m
American Airlines
Mon 8/316:53 pm
ORD
- STL
Nonstop1h 26m
American Airlines
Deal found 2/11![American Airlines logo]()
$207
This Southwest deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/176:15 am
STL
- MDW
2 stops6h 40m
Southwest
Wed 3/1811:30 am
MDW
- STL
1 stop5h 30m
Southwest
Deal found 2/11![Southwest logo]()
$202
This Southwest deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/315:40 am
STL
- MDW
Nonstop1h 10m
Southwest
Thu 4/211:15 am
MDW
- STL
Nonstop1h 15m
Southwest
Deal found 2/11![Southwest logo]()
$194
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 February 13, 2026.
Search for one-way flight options from St. Louis to Illinois. Find affordable one-way fares based on user searches. Data last updated February 13, 2026.
This Southwest deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/104:00 pm
STL
- MDW
Nonstop1h 05m
Southwest
Deal found 2/10![Southwest logo]()
$49
This United Airlines deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 3/188:17 am
STL
- ORD
Nonstop1h 33m
United Airlines
Deal found 2/11![United Airlines logo]()
$49
This Southwest deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/107:30 am
STL
- ORD
1 stop5h 20m
Southwest
Deal found 2/10![Southwest logo]()
$59
This Kiwi.com deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/1111:32 am
STL
- ORD
1 stop6h 25m
Frontier
Deal found 2/10![Frontier logo]()
$61
This Southwest deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/36:50 am
STL
- MDW
2 stops7h 05m
Southwest
Deal found 2/10![Southwest logo]()
$64
This Kiwi.com deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 2/258:17 pm
STL
- MDW
1 stop19h 59m
Frontier
Deal found 2/10![Frontier logo]()
$67
This Kiwi.com deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/92:09 pm
STL
- MDW
1 stop8h 10m
Frontier
Deal found 2/10![Frontier logo]()
$68
This American Airlines deal was found by Cheapflights users on 2/11. Clicking the “Pick Dates” 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 5/37:05 am
STL
- ORD
Nonstop1h 31m
American Airlines
Deal found 2/11![American Airlines logo]()
$69
This Kiwi.com deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/92:09 pm
STL
- ORD
1 stop18h 14m
Frontier
Deal found 2/10![Frontier logo]()
$72
This Kiwi.com deal was found by Cheapflights users on 2/9. Clicking the “Pick Dates” 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 2/208:20 pm
STL
- MDW
1 stop25h 13m
Frontier
Deal found 2/9![Frontier logo]()
$77
This United Airlines deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” 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 3/37:41 am
STL
- ORD
Nonstop1h 29m
United Airlines
Deal found 2/10![United Airlines logo]()
$78
This Delta deal was found by Cheapflights users on 2/12. Clicking the “Pick Dates” 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 4/86:00 am
STL
- MDW
1 stop6h 02m
Delta
Deal found 2/12![Delta logo]()
$79
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 February 13, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $191 (Delta) |
One-way from | $49 (Southwest) |
Popular in | January |
Cheapest in | August |
Average price | $417 |
Good round-trip deal | $338 or less |
Good one-way deal | $198 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 2,558,603 searches. Data last updated February 13, 2026.
Use the filters below to find and compare flights from St. Louis to Illinois that are best for you.
Fly from
St. Louis
Fly to
Illinois
Route
Depart
Return
Price
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Thu 3/5
6:35 am-12:46 pm
1 stop6h 11m
Chicago Midway
Mon 3/9
1:10 pm-4:32 pm
1 stop3h 22m
$191
St. LouisChicago
STL - ORD
STLORD
Lambert-St Louis
Sat 3/7
7:35 am-12:50 pm
1 stop5h 15m
Chicago O'Hare Intl
Mon 3/9
4:15 pm-10:10 pm
1 stop5h 55m
$191
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Sat 3/28
12:28 pm-6:40 pm
1 stop6h 12m
Chicago Midway
Sat 4/4
9:30 am-2:24 pm
1 stop4h 54m
$191
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Sat 5/2
12:23 pm-6:36 pm
1 stop6h 13m
Chicago Midway
Mon 5/4
7:16 pm-11:13 pm
1 stop3h 57m
$191
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Sat 4/4
6:32 am-12:29 pm
1 stop5h 57m
Chicago Midway
Sat 4/4
7:20 pm-11:25 pm
1 stop4h 05m
$191
St. LouisChicago
STL - ORD
STLORD
Lambert-St Louis
Sat 3/28
10:50 am-4:18 pm
1 stop5h 28m
Chicago O'Hare Intl
Sat 4/4
9:35 am-2:24 pm
1 stop4h 49m
$191
St. LouisChicago
STL - ORD
STLORD
Lambert-St Louis
Thu 3/5
6:35 am-1:20 pm
1 stop6h 45m
Chicago O'Hare Intl
Mon 3/9
5:59 pm-11:58 pm
1 stop5h 59m
$191
St. LouisChicago
STL - ORD
STLORD
Lambert-St Louis
Sat 4/4
6:32 am-1:24 pm
1 stop6h 52m
Chicago O'Hare Intl
Sat 4/4
5:59 pm-11:58 pm
1 stop5h 59m
$191
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Sat 3/7
5:45 pm-12:50 am
2 stops7h 05m
Chicago Midway
Mon 3/9
7:00 pm-12:05 am
1 stop5h 05m
$196
St. LouisChicago
STL - ORD
STLORD
Lambert-St Louis
Sat 5/2
3:25 pm-7:48 pm
1 stop4h 23m
Chicago O'Hare Intl
Mon 5/4
1:36 pm-11:13 pm
2 stops9h 37m
$196
Showing 1-10 of 39 results
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-DEC
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-DEC
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 $77). Flying from St. Louis to Illinois in March is currently the most expensive (average of $173). 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 February 13, 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 34% versus a flight at noon.
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 February 7, 2026.
Travelers seeking maximum savings on their St. Louis to Illinois flight should consider departing on Tuesday at noon when fares are most often at their lowest. Saturday evenings flights should be avoided if possible as fares are typically the most expensive at this time.
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 February 13, 2026.
The most flights from STL to USIL are scheduled on a Thursday (67 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (17 on average).
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 February 13, 2026.
See what other customers who have flown with Southwest, United Airlines, and American 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.
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Related info for your journey
Find useful and relevant information for your journey from St. Louis to Illinois. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
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Alternative routes for 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 February 13, 2026.
Popular flight searches
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St. Louis to Illinois flights
Consider these flights traveling from St. Louis to Illinois.
Top 4 airlines flying from St. Louis to Illinois
Discover the top 4 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 2,558,603 searches. Data last updated February 13, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$97 | Average$293 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$114 | Average$330 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$117 | Average$336 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$140 | Average$203 | FlexibilityNo cancel fee | On-timeN/A |