$49+ Cheap flights from Illinois to St. Louis (STL)
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 5/6. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — STL
Mar 15 — Mar 221
1 adult, Economy
We work with more than 300 partners to bring you better travel deals
Find cheap flights from Illinois to St. Louis 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
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Illinois to St. Louis
Cheapest
Best
Last-minute
One-way
Cheapest flights from Illinois to St. LouisExplore the most affordable flight options available from Illinois to St. Louis. 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 Illinois to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 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 3/108:15 am
MDW
- STL
Nonstop1h 20m
Southwest
Wed 3/1110:30 am
STL
- MDW
Nonstop1h 10m
Southwest
Deal found 2/10![Southwest logo]()
$97
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 3/109:33 pm
ORD
- STL
Nonstop1h 26m
United Airlines
Wed 3/118:17 am
STL
- ORD
Nonstop1h 33m
United Airlines
Deal found 2/10![United Airlines logo]()
$97
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.
Thu 3/510:34 pm
ORD
- STL
Nonstop1h 14m
American Airlines
Sun 3/86:00 am
STL
- ORD
Nonstop1h 28m
American Airlines
Deal found 2/12![American Airlines logo]()
$98
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 3/104:15 pm
ORD
- STL
1 stop5h 10m
Southwest
Wed 3/117:30 am
STL
- ORD
1 stop5h 20m
Southwest
Deal found 2/10![Southwest logo]()
$117
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.
Thu 3/55:16 pm
MDW
- STL
1 stop18h 33m
Frontier
Mon 3/92:09 pm
STL
- MDW
1 stop5h 38m
Frontier
Deal found 2/10![Frontier logo]()
$132
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.
Mon 3/911:15 am
MDW
- STL
Nonstop1h 15m
Southwest
Wed 3/115:40 am
STL
- MDW
Nonstop1h 10m
Southwest
Deal found 2/10![Southwest logo]()
$134
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.
Mon 3/97:42 pm
ORD
- STL
Nonstop1h 25m
United Airlines
Wed 3/118:17 am
STL
- ORD
Nonstop1h 33m
United Airlines
Deal found 2/10![United Airlines logo]()
$134
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/710:23 am
ORD
- STL
Nonstop1h 22m
American Airlines
Wed 5/137:05 am
STL
- ORD
Nonstop1h 31m
American Airlines
Deal found 2/10![American Airlines logo]()
$136
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.
Fri 3/65:05 am
ORD
- STL
1 stop6h 44m
Frontier
Mon 3/92:09 pm
STL
- ORD
1 stop18h 14m
Frontier
Deal found 2/10![Frontier logo]()
$146
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.
Wed 3/256:00 am
MDW
- STL
1 stop5h 30m
Southwest
Thu 3/264:05 pm
STL
- MDW
1 stop4h 15m
Southwest
Deal found 2/12![Southwest logo]()
$154
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.
Wed 3/114:15 pm
ORD
- STL
1 stop5h 10m
Southwest
Wed 3/187:30 am
STL
- ORD
1 stop5h 20m
Southwest
Deal found 2/11![Southwest logo]()
$154
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.
Thu 3/512:44 pm
ORD
- STL
1 stop11h 15m
Multiple Airlines
Mon 3/92:09 pm
STL
- ORD
1 stop18h 14m
Multiple Airlines
Deal found 2/10![Multiple Airlines logo]()
$156
Best flights from Illinois to St. LouisDiscover carefully curated flight deals from Illinois to St. Louis 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 Illinois to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. 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 3/1710:30 am
MDW
- STL
Nonstop1h 10m
Southwest
Tue 3/174:00 pm
STL
- MDW
Nonstop1h 05m
Southwest
Deal found 2/10![Southwest logo]()
$97
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/19:30 pm
ORD
- STL
Nonstop1h 26m
United Airlines
Sat 4/46:30 am
STL
- ORD
Nonstop1h 29m
United Airlines
Deal found 2/12![United Airlines logo]()
$134
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.
Tue 3/105:30 am
ORD
- STL
1 stop5h 39m
Delta
Tue 3/105:21 pm
STL
- ORD
1 stop6h 33m
Delta
Deal found 2/12![Delta logo]()
$157
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/110:55 am
ORD
- STL
1 stop8h 17m
Frontier
Mon 5/49:55 pm
STL
- ORD
1 stop8h 52m
Frontier
Deal found 2/10![Frontier logo]()
$160
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.
Thu 3/55:16 pm
MDW
- STL
1 stop18h 33m
Multiple Airlines
Mon 3/94:51 pm
STL
- MDW
2 stops20h 11m
Multiple Airlines
Deal found 2/9![Multiple Airlines logo]()
$173
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.
Wed 3/113:20 pm
MDW
- STL
1 stop4h 40m
Southwest
Wed 3/188:50 pm
STL
- MDW
Nonstop1h 05m
Southwest
Deal found 2/11![Southwest logo]()
$107
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 5/72:10 pm
MDW
- STL
Nonstop1h 15m
Southwest
Wed 5/135:35 am
STL
- MDW
Nonstop1h 10m
Southwest
Deal found 2/10![Southwest logo]()
$134
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.
Tue 4/1410:49 am
ORD
- STL
1 stop5h 53m
Delta
Tue 4/211:45 pm
STL
- ORD
1 stop6h 55m
Delta
Deal found 2/11![Delta logo]()
$157
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/247:42 pm
ORD
- STL
Nonstop1h 25m
United Airlines
Wed 3/255:00 am
STL
- ORD
Nonstop1h 30m
United Airlines
Deal found 2/12![United Airlines logo]()
$157
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.
Wed 3/258:15 am
MDW
- STL
Nonstop1h 20m
Southwest
Thu 3/264:45 pm
STL
- MDW
Nonstop1h 05m
Southwest
Deal found 2/12![Southwest logo]()
$134
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 3/177:10 am
ORD
- STL
1 stop5h 48m
Delta
Tue 3/175:21 pm
STL
- ORD
1 stop6h 33m
Delta
Deal found 2/10![Delta logo]()
$157
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.
Mon 3/911:15 am
MDW
- STL
Nonstop1h 15m
Southwest
Wed 3/115:40 am
STL
- MDW
Nonstop1h 10m
Southwest
Deal found 2/10![Southwest logo]()
$134
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/99:33 pm
ORD
- STL
Nonstop1h 26m
United Airlines
Mon 3/167:40 am
STL
- ORD
Nonstop1h 29m
United Airlines
Deal found 2/12![United Airlines logo]()
$171
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.
Tue 3/245:59 pm
ORD
- STL
1 stop5h 59m
Delta
Wed 3/256:32 am
STL
- ORD
1 stop6h 45m
Delta
Deal found 2/12![Delta logo]()
$157
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/77:40 pm
ORD
- STL
Nonstop1h 28m
United Airlines
Sat 5/910:00 am
STL
- ORD
Nonstop1h 33m
United Airlines
Deal found 2/9![United Airlines logo]()
$171
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 5/129:00 am
ORD
- STL
1 stop4h 05m
Delta
Tue 5/125:15 pm
STL
- ORD
1 stop5h 13m
Delta
Deal found 2/10![Delta logo]()
$167
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.
Wed 4/87:45 am
MDW
- STL
1 stop5h 15m
Southwest
Sat 4/1110:35 am
STL
- MDW
1 stop6h 25m
Southwest
Deal found 2/10![Southwest logo]()
$154
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.
Wed 4/82:40 pm
ORD
- STL
1 stop4h 40m
Southwest
Sat 4/1110:55 am
STL
- ORD
1 stop4h 35m
Southwest
Deal found 2/10![Southwest logo]()
$154
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.
Mon 4/139:00 am
MDW
- STL
Nonstop1h 15m
Southwest
Mon 4/134:40 pm
STL
- MDW
Nonstop1h 10m
Southwest
Deal found 2/10![Southwest logo]()
$171
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.
Fri 4/35:00 am
SPI
- STL
1 stop18h 35m
American Airlines
Sun 4/56:00 am
STL
- SPI
1 stop36h 03m
American Airlines
Deal found 2/12![American Airlines logo]()
$629
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.
Thu 3/55:40 pm
MDW
- STL
Nonstop1h 15m
Southwest
Mon 3/95:30 am
STL
- MDW
Nonstop1h 10m
Southwest
Deal found 2/9![Southwest logo]()
$171
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 2/2510:06 am
SPI
- STL
1 stop12h 21m
Multiple Airlines
Sun 3/110:11 pm
STL
- SPI
2 stops59h 15m
Multiple Airlines
Deal found 2/10![Multiple Airlines logo]()
$439
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/256:54 pm
SPI
- STL
1 stop28h 54m
American Airlines
Sun 3/16:38 pm
STL
- SPI
1 stop49h 07m
American Airlines
Deal found 2/10![American Airlines logo]()
$777
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.
Fri 3/65:00 am
SPI
- STL
1 stop18h 35m
American Airlines
Fri 3/139:37 am
STL
- SPI
1 stop8h 26m
American Airlines
Deal found 2/12![American Airlines logo]()
$821
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.
Fri 2/276:54 pm
SPI
- STL
1 stop15h 19m
American Airlines
Tue 3/36:00 am
STL
- SPI
1 stop17h 32m
American Airlines
Deal found 2/11![American Airlines logo]()
$891
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 8/26:00 am
SPI
- STL
1 stop7h 41m
American Airlines
Sun 8/25:00 pm
STL
- SPI
1 stop45h 20m
American Airlines
Deal found 2/11![American Airlines logo]()
$1,222
Last-minute flights from Illinois to St. LouisDiscover last-minute flight deals from Illinois to St. Louis. Data last updated February 13, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to St. Louis. Data last updated February 13, 2026 and is based on user searches.
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.
Thu 3/57:18 am
ORD
- STL
Nonstop1h 23m
American Airlines
Sun 3/86:00 am
STL
- ORD
Nonstop1h 28m
American Airlines
Deal found 2/12![American Airlines logo]()
$98
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.
Thu 3/55:16 pm
MDW
- STL
1 stop18h 33m
Frontier
Mon 3/92:09 pm
STL
- MDW
1 stop5h 38m
Frontier
Deal found 2/10![Frontier logo]()
$132
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.
Thu 3/512:44 pm
ORD
- STL
1 stop11h 15m
Multiple Airlines
Mon 3/92:09 pm
STL
- ORD
1 stop18h 14m
Multiple Airlines
Deal found 2/10![Multiple Airlines logo]()
$156
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.
Fri 3/65:05 am
ORD
- STL
1 stop6h 44m
Frontier
Mon 3/92:09 pm
STL
- ORD
1 stop18h 14m
Frontier
Deal found 2/10![Frontier logo]()
$146
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.
Mon 3/911:15 am
MDW
- STL
Nonstop1h 15m
Southwest
Wed 3/115:40 am
STL
- MDW
Nonstop1h 10m
Southwest
Deal found 2/10![Southwest logo]()
$134
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.
Mon 3/97:42 pm
ORD
- STL
Nonstop1h 25m
United Airlines
Wed 3/118:17 am
STL
- ORD
Nonstop1h 33m
United Airlines
Deal found 2/10![United Airlines logo]()
$134
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 3/108:15 am
MDW
- STL
Nonstop1h 20m
Southwest
Wed 3/1110:30 am
STL
- MDW
Nonstop1h 10m
Southwest
Deal found 2/10![Southwest logo]()
$97
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 3/109:33 pm
ORD
- STL
Nonstop1h 26m
United Airlines
Wed 3/118:17 am
STL
- ORD
Nonstop1h 33m
United Airlines
Deal found 2/10![United Airlines logo]()
$97
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 3/104:15 pm
ORD
- STL
1 stop5h 10m
Southwest
Wed 3/117:30 am
STL
- ORD
1 stop5h 20m
Southwest
Deal found 2/10![Southwest logo]()
$117
This Delta deal was found by Cheapflights users on 2/13. Clicking the “Pick Dates” 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 3/106:00 am
MDW
- STL
1 stop5h 09m
Delta
Tue 3/105:21 pm
STL
- MDW
1 stop5h 10m
Delta
Deal found 2/13![Delta logo]()
$157
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.
Wed 3/114:15 pm
ORD
- STL
1 stop5h 10m
Southwest
Wed 3/187:30 am
STL
- ORD
1 stop5h 20m
Southwest
Deal found 2/11![Southwest logo]()
$154
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.
Wed 3/256:00 am
MDW
- STL
1 stop5h 30m
Southwest
Thu 3/264:05 pm
STL
- MDW
1 stop4h 15m
Southwest
Deal found 2/12![Southwest logo]()
$154
One-way flights from Illinois to St. LouisSearch for one-way flight options from Illinois to St. Louis. Find affordable one-way fares based on user searches. Data last updated February 13, 2026.
Search for one-way flight options from Illinois to St. Louis. Find affordable one-way fares based on user searches. Data last updated February 13, 2026.
This Southwest deal was found by Cheapflights users on 2/13. Clicking the “Pick Dates” 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 3/319:05 pm
MDW
- STL
Nonstop1h 15m
Southwest
Deal found 2/13![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.
Tue 3/317:40 pm
ORD
- STL
Nonstop1h 28m
United Airlines
Deal found 2/11![United Airlines logo]()
$49
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.
Fri 5/110:30 pm
ORD
- STL
Nonstop1h 16m
American Airlines
Deal found 2/12![American Airlines logo]()
$50
This Southwest deal was found by Cheapflights users on 2/13. Clicking the “Pick Dates” 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 3/312:40 pm
ORD
- STL
1 stop5h 15m
Southwest
Deal found 2/13![Southwest logo]()
$59
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 4/711:35 am
MDW
- STL
2 stops6h 20m
Southwest
Deal found 2/10![Southwest logo]()
$64
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.
Wed 4/152:40 pm
ORD
- STL
1 stop7h 20m
Southwest
Deal found 2/10![Southwest logo]()
$64
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 3/66:05 am
MDW
- STL
1 stop5h 44m
Frontier
Deal found 2/11![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 3/96:05 am
MDW
- STL
1 stop7h 14m
Frontier
Deal found 2/10![Frontier logo]()
$68
This American Airlines deal was found by Cheapflights users on 2/13. Clicking the “Pick Dates” 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 5/36:59 am
ORD
- STL
Nonstop1h 25m
American Airlines
Deal found 2/13![American Airlines logo]()
$69
This Kiwi.com deal was found by Cheapflights users on 2/13. Clicking the “Pick Dates” 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 3/107:41 pm
ORD
- STL
1 stop14h 56m
Frontier
Deal found 2/13![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 3/37:40 pm
ORD
- STL
Nonstop1h 25m
United Airlines
Deal found 2/10![United Airlines logo]()
$78
This Southwest deal was found by Cheapflights users on 2/13. Clicking the “Pick Dates” 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 3/104:45 pm
MDW
- STL
Nonstop1h 15m
Southwest
Deal found 2/13![Southwest logo]()
$79
Find flight deals from Illinois to St. Louis
Keep the following information in mind while searching for Illinois to St. Louis flight deals. Data was last updated February 13, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $97 (Southwest) |
One-way from | $49 (Southwest) |
Popular in | January |
Cheapest in | December |
Average price | $498 |
Good round-trip deal | $61 or less |
Good one-way deal | $208 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Illinois to St. Louis 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 Illinois to St. Louis that are best for you.
Fly from
Illinois
Fly to
St. Louis
Route
Depart
Return
Price
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Tue 3/17
10:30 am-11:40 am
Nonstop1h 10m
Lambert-St Louis
Tue 3/17
4:00 pm-5:05 pm
Nonstop1h 05m
$97
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Wed 3/11
3:20 pm-8:00 pm
1 stop4h 40m
Lambert-St Louis
Wed 3/18
8:50 pm-9:55 pm
Nonstop1h 05m
$107
ChicagoSt. Louis
ORD - STL
ORDSTL
Chicago O'Hare Intl
Wed 4/1
9:30 pm-10:56 pm
Nonstop1h 26m
Lambert-St Louis
Sat 4/4
6:30 am-7:59 am
Nonstop1h 29m
$134
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Thu 5/7
2:10 pm-3:25 pm
Nonstop1h 15m
Lambert-St Louis
Wed 5/13
5:35 am-6:45 am
Nonstop1h 10m
$134
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Wed 3/25
8:15 am-9:35 am
Nonstop1h 20m
Lambert-St Louis
Thu 3/26
4:45 pm-5:50 pm
Nonstop1h 05m
$134
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Mon 3/9
11:15 am-12:30 pm
Nonstop1h 15m
Lambert-St Louis
Wed 3/11
5:40 am-6:50 am
Nonstop1h 10m
$134
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Wed 4/8
7:45 am-1:00 pm
1 stop5h 15m
Lambert-St Louis
Sat 4/11
10:35 am-5:00 pm
1 stop6h 25m
$154
ChicagoSt. Louis
ORD - STL
ORDSTL
Chicago O'Hare Intl
Wed 4/8
2:40 pm-7:20 pm
1 stop4h 40m
Lambert-St Louis
Sat 4/11
10:55 am-3:30 pm
1 stop4h 35m
$154
ChicagoSt. Louis
ORD - STL
ORDSTL
Chicago O'Hare Intl
Tue 3/10
5:30 am-11:09 am
1 stop5h 39m
Lambert-St Louis
Tue 3/10
5:21 pm-11:54 pm
1 stop6h 33m
$157
ChicagoSt. Louis
ORD - STL
ORDSTL
Chicago O'Hare Intl
Tue 4/14
10:49 am-4:42 pm
1 stop5h 53m
Lambert-St Louis
Tue 4/21
1:45 pm-8:40 pm
1 stop6h 55m
$157
Showing 1-10 of 42 results
Best time to book a flight from Illinois to St. Louis
Have a flexible travel schedule? Discover the best time to fly to St. Louis from Illinois with our price prediction graph.
MDW-STL
ORD-STL
SPI-STL
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Illinois to St. Louis
USIL-STL
MDW-STL
ORD-STL
SPI-STL
What is the cheapest month to book a flight from Illinois to St. Louis?
Currently, August is the cheapest month in which you can book a flight from Illinois to St. Louis (average of $77). Flying from Illinois to St. Louis in February is currently the most expensive (average of $228). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
What is the cheapest time of day to fly from IL to STL?
Find hourly flight availability from Illinois to St. Louis. 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.
It’s typically best to fly out from Illinois to St. Louis at noon. Doing so could potentially save you 21% on the flight price compared to flying in the afternoon, which is usually more expensive.
What is the cheapest day to fly from Illinois to St. Louis?
Use this chart to determine the cheapest time to fly round-trip from Illinois to St. Louis. Price data was last updated on February 7, 2026.
Travelers seeking maximum savings on their Illinois to St. Louis flight should consider departing on Tuesday at noon when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.
Weekly flight availability from Illinois to St. Louis
Explore weekly flight availability from Illinois to St. Louis. 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 USIL to STL are scheduled on a Friday (63 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (34 on average).
Related info for your journey
Find useful and relevant information for your journey from Illinois to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsEdwardsville
O'Fallon
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Glencoe
Chesterfield
Alton
Farmington
Festus
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
Alternative routes
Complete your trip
Flights by cabin class
Other flight options
Popular flights
St. Louis flight routes
Top destinations
Alternative routes for Illinois to St. Louis
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to St. Louis by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Illinois to St. Louis by cabin class
Find flights from Illinois to St. Louis, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Illinois and St. Louis flights
Browse other Illinois and St. Louis flight options. Last updated on February 13, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Other flights to St. Louis
Explore flights to St. Louis departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on February 13, 2026.
Illinois to St. Louis flights
Consider these flights traveling from Illinois to St. Louis.
Top 4 airlines flying from Illinois to St. Louis
Discover the top 4 airlines that operate flights from Illinois to St. Louis. 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$77 | Average$423 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$121 | Average$312 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$144 | Average$337 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$156 | Average$215 | FlexibilityNo cancel fee | On-timeN/A |