$59+ 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 6/2. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — STL
Jun 12 — Jun 191
Round-trip
1 adult, Economy
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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
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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 May 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 May 13, 2026.
This Frontier deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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.
Mon 5/184:52 pm
MDW
- STL
1 stop7h 29m
Frontier
Wed 8/54:52 pm
STL
- MDW
1 stop5h 16m
Frontier
Deal found 5/8![Frontier logo]()
$250
This Frontier deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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.
Mon 5/185:30 pm
ORD
- STL
1 stop6h 51m
Frontier
Tue 8/117:03 pm
STL
- ORD
1 stop10h 25m
Frontier
Deal found 5/8![Frontier logo]()
$250
This Kiwi.com deal was found by Cheapflights users on 5/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/246:00 am
MDW
- STL
2 stops18h 14m
Frontier
Fri 8/285:33 pm
STL
- MDW
1 stop17h 31m
Frontier
Deal found 5/12![Frontier logo]()
$251
This Frontier deal was found by Cheapflights users on 5/12. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/289:37 pm
ORD
- STL
1 stop21h 46m
Frontier
Mon 6/111:24 am
STL
- ORD
1 stop11h 49m
Frontier
Deal found 5/12![Frontier logo]()
$251
This Kiwi.com deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/245:11 pm
ORD
- STL
2 stops27h 00m
Frontier
Tue 8/116:33 pm
STL
- ORD
1 stop13h 20m
Frontier
Deal found 5/8![Frontier logo]()
$252
This Kiwi.com deal was found by Cheapflights users on 5/11. 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.
Thu 5/286:55 am
ORD
- STL
2 stops12h 28m
Frontier
Wed 6/105:06 pm
STL
- ORD
1 stop14h 57m
Frontier
Deal found 5/11![Frontier logo]()
$255
This Booking.com deal was found by Cheapflights users on 5/10. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/1410:16 am
ORD
- STL
1 stop13h 43m
Frontier
Sat 8/154:09 pm
STL
- ORD
1 stop6h 56m
Frontier
Deal found 5/10![Frontier logo]()
$256
This Delta deal was found by Cheapflights users on 5/11. 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.
Fri 6/125:11 pm
MDW
- STL
1 stop6h 45m
Delta
Tue 6/1611:13 am
STL
- MDW
1 stop7h 05m
Delta
Deal found 5/11![Delta logo]()
$257
This Delta deal was found by Cheapflights users on 5/12. 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.
Fri 6/122:07 pm
ORD
- STL
1 stop6h 32m
Delta
Tue 6/161:59 pm
STL
- ORD
1 stop6h 32m
Delta
Deal found 5/12![Delta logo]()
$257
This Kiwi.com deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/246:00 am
MDW
- STL
1 stop11h 33m
Frontier
Mon 8/104:52 pm
STL
- MDW
1 stop18h 15m
Frontier
Deal found 5/8![Frontier logo]()
$259
This Frontier deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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 5/235:11 pm
ORD
- STL
1 stop6h 46m
Frontier
Thu 8/64:09 pm
STL
- ORD
1 stop6h 56m
Frontier
Deal found 5/8![Frontier logo]()
$260
This Booking.com deal was found by Cheapflights users on 5/12. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/269:37 pm
ORD
- STL
1 stop21h 46m
Frontier
Fri 5/294:19 pm
STL
- ORD
1 stop6h 54m
Frontier
Deal found 5/12![Frontier logo]()
$262
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 May 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 May 13, 2026.
This Delta deal was found by Cheapflights users on 5/11. 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.
Fri 6/125:11 pm
MDW
- STL
1 stop6h 45m
Delta
Tue 6/1611:13 am
STL
- MDW
1 stop7h 05m
Delta
Deal found 5/11![Delta logo]()
$257
This Kiwi.com deal was found by Cheapflights users on 5/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/96:00 am
MDW
- STL
1 stop11h 30m
Frontier
Tue 6/98:08 pm
STL
- MDW
2 stops15h 01m
Frontier
Deal found 5/12![Frontier logo]()
$264
This Southwest deal was found by Cheapflights users on 5/11. 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.
Mon 6/89:35 pm
MDW
- STL
Nonstop1h 15m
Southwest
Mon 6/1512:50 pm
STL
- MDW
1 stop4h 15m
Southwest
Deal found 5/11![Southwest logo]()
$274
This United Airlines deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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 8/1410:29 am
ORD
- STL
Nonstop1h 33m
United Airlines
Sun 8/1612:59 pm
STL
- ORD
Nonstop1h 31m
United Airlines
Deal found 5/8![United Airlines logo]()
$337
This Delta deal was found by Cheapflights users on 5/12. 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 6/108:52 am
ORD
- STL
1 stop4h 17m
Delta
Thu 6/1110:20 am
STL
- ORD
1 stop6h 06m
Delta
Deal found 5/12![Delta logo]()
$257
This Southwest deal was found by Cheapflights users on 5/12. 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.
Thu 6/411:00 am
MDW
- STL
Nonstop1h 10m
Southwest
Sun 6/75:50 am
STL
- MDW
Nonstop1h 05m
Southwest
Deal found 5/12![Southwest logo]()
$275
This Delta deal was found by Cheapflights users on 5/11. 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.
Fri 6/126:22 pm
ORD
- STL
1 stop5h 34m
Delta
Tue 6/166:21 am
STL
- ORD
1 stop5h 10m
Delta
Deal found 5/11![Delta logo]()
$257
This Southwest deal was found by Cheapflights users on 5/9. 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.
Sat 5/309:05 am
MDW
- STL
1 stop7h 20m
Southwest
Mon 6/19:40 pm
STL
- MDW
Nonstop1h 05m
Southwest
Deal found 5/9![Southwest logo]()
$285
This Delta deal was found by Cheapflights users on 5/12. 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 6/98:52 am
ORD
- STL
2 stops7h 54m
Delta
Wed 6/106:21 am
STL
- ORD
2 stops6h 43m
Delta
Deal found 5/12![Delta logo]()
$265
This American Airlines deal was found by Cheapflights users on 5/10. 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 7/22:55 pm
SPI
- STL
1 stop26h 51m
American Airlines
Tue 7/71:25 pm
STL
- SPI
1 stop24h 59m
American Airlines
Deal found 5/10![American Airlines logo]()
$664
This Delta deal was found by Cheapflights users on 5/9. 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.
Sat 6/61:44 pm
ORD
- STL
2 stops9h 37m
Delta
Sat 6/1311:18 am
STL
- ORD
1 stop6h 09m
Delta
Deal found 5/9![Delta logo]()
$289
This Southwest deal was found by Cheapflights users on 5/12. 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.
Sat 10/1010:25 am
MDW
- STL
2 stops6h 25m
Southwest
Mon 10/128:30 am
STL
- MDW
1 stop3h 25m
Southwest
Deal found 5/12![Southwest logo]()
$321
This Southwest deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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 5/221:30 pm
MDW
- STL
1 stop5h 20m
Southwest
Mon 6/11:45 pm
STL
- MDW
Nonstop1h 10m
Southwest
Deal found 5/8![Southwest logo]()
$325
This Delta deal was found by Cheapflights users on 5/11. 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.
Mon 6/15:19 pm
ORD
- STL
1 stop3h 50m
Delta
Tue 6/301:39 pm
STL
- ORD
1 stop6h 53m
Delta
Deal found 5/11![Delta logo]()
$297
This Delta deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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 5/231:22 pm
MDW
- STL
1 stop3h 54m
Delta
Tue 8/112:10 pm
STL
- MDW
1 stop4h 23m
Delta
Deal found 5/8![Delta logo]()
$308
This Southwest deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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 5/224:15 pm
ORD
- STL
1 stop8h 00m
Southwest
Mon 6/15:45 am
STL
- ORD
1 stop9h 45m
Southwest
Deal found 5/8![Southwest logo]()
$340
This Delta deal was found by Cheapflights users on 5/9. 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.
Thu 6/45:15 pm
MDW
- STL
1 stop6h 44m
Delta
Sun 6/76:21 am
STL
- MDW
2 stops6h 25m
Delta
Deal found 5/9![Delta logo]()
$334
This Delta deal was found by Cheapflights users on 5/10. 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 7/162:07 pm
ORD
- STL
2 stops9h 15m
Delta
Mon 7/2011:18 am
STL
- ORD
2 stops9h 13m
Delta
Deal found 5/10![Delta logo]()
$339
This American Airlines deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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 5/246:00 am
SPI
- STL
1 stop17h 54m
American Airlines
Thu 5/285:00 pm
STL
- SPI
1 stop45h 01m
American Airlines
Deal found 5/8![American Airlines logo]()
$724
This Delta deal was found by Cheapflights users on 5/12. 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 8/56:51 am
ORD
- STL
2 stops10h 01m
Delta
Wed 9/166:45 am
STL
- ORD
1 stop5h 54m
Delta
Deal found 5/12![Delta logo]()
$343
This American Airlines deal was found by Cheapflights users on 5/10. 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.
Mon 6/86:00 am
SPI
- STL
1 stop18h 16m
American Airlines
Sun 6/141:42 pm
STL
- SPI
1 stop48h 27m
American Airlines
Deal found 5/10![American Airlines logo]()
$727
This Delta deal was found by Cheapflights users on 5/10. 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.
Sun 6/77:01 am
ORD
- STL
1 stop6h 08m
Delta
Thu 6/1110:20 am
STL
- ORD
1 stop6h 06m
Delta
Deal found 5/10![Delta logo]()
$365
This American Airlines deal was found by Cheapflights users on 5/12. 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.
Tue 5/266:00 am
SPI
- STL
1 stop41h 54m
American Airlines
Fri 5/299:08 am
STL
- SPI
1 stop28h 53m
American Airlines
Deal found 5/12![American Airlines logo]()
$757
This American Airlines deal was found by Cheapflights users on 5/11. 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 5/266:00 am
SPI
- STL
1 stop26h 32m
American Airlines
Sat 5/307:00 am
STL
- SPI
1 stop16h 47m
American Airlines
Deal found 5/11![American Airlines logo]()
$808
This American Airlines deal was found by Cheapflights users on 5/10. 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.
Tue 6/26:15 am
SPI
- STL
1 stop8h 11m
American Airlines
Thu 6/48:14 pm
STL
- SPI
1 stop41h 55m
American Airlines
Deal found 5/10![American Airlines logo]()
$861
Last-minute flights from Illinois to St. LouisDiscover last-minute flight deals from Illinois to St. Louis. Data last updated May 13, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to St. Louis. Data last updated May 13, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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.
Mon 5/184:52 pm
MDW
- STL
1 stop7h 29m
Frontier
Wed 8/54:52 pm
STL
- MDW
1 stop5h 16m
Frontier
Deal found 5/8![Frontier logo]()
$250
This Frontier deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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.
Mon 5/185:30 pm
ORD
- STL
1 stop6h 51m
Frontier
Tue 8/117:03 pm
STL
- ORD
1 stop10h 25m
Frontier
Deal found 5/8![Frontier logo]()
$250
This Frontier deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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 5/235:11 pm
ORD
- STL
1 stop6h 46m
Frontier
Thu 8/64:09 pm
STL
- ORD
1 stop6h 56m
Frontier
Deal found 5/8![Frontier logo]()
$260
This Kiwi.com deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/245:11 pm
ORD
- STL
2 stops27h 00m
Frontier
Tue 8/116:33 pm
STL
- ORD
1 stop13h 20m
Frontier
Deal found 5/8![Frontier logo]()
$252
This Kiwi.com deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/246:00 am
MDW
- STL
1 stop11h 33m
Frontier
Mon 8/104:52 pm
STL
- MDW
1 stop18h 15m
Frontier
Deal found 5/8![Frontier logo]()
$259
This Booking.com deal was found by Cheapflights users on 5/12. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/269:37 pm
ORD
- STL
1 stop21h 46m
Frontier
Fri 5/294:19 pm
STL
- ORD
1 stop6h 54m
Frontier
Deal found 5/12![Frontier logo]()
$262
This Frontier deal was found by Cheapflights users on 5/12. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/289:37 pm
ORD
- STL
1 stop21h 46m
Frontier
Mon 6/111:24 am
STL
- ORD
1 stop11h 49m
Frontier
Deal found 5/12![Frontier logo]()
$251
This Kiwi.com deal was found by Cheapflights users on 5/11. 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.
Thu 5/286:55 am
ORD
- STL
2 stops12h 28m
Frontier
Wed 6/105:06 pm
STL
- ORD
1 stop14h 57m
Frontier
Deal found 5/11![Frontier logo]()
$255
This Southwest deal was found by Cheapflights users on 5/8. Clicking the “Pick Dates” 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 6/31:55 pm
MDW
- STL
Nonstop1h 10m
Southwest
Sun 6/75:50 am
STL
- MDW
Nonstop1h 05m
Southwest
Deal found 5/8![Southwest logo]()
$264
This Kiwi.com deal was found by Cheapflights users on 5/11. 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.
Mon 6/84:05 pm
ORD
- STL
2 stops27h 18m
Frontier
Mon 6/155:06 pm
STL
- ORD
1 stop26h 44m
Frontier
Deal found 5/11![Frontier logo]()
$263
This Delta deal was found by Cheapflights users on 5/12. 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.
Fri 6/121:26 pm
MDW
- STL
1 stop3h 57m
Delta
Tue 6/166:30 am
STL
- MDW
1 stop6h 16m
Delta
Deal found 5/12![Delta logo]()
$257
This Delta deal was found by Cheapflights users on 5/12. 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.
Fri 6/122:07 pm
ORD
- STL
1 stop6h 32m
Delta
Tue 6/161:59 pm
STL
- ORD
1 stop6h 32m
Delta
Deal found 5/12![Delta logo]()
$257
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 May 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 May 13, 2026.
This Southwest deal was found by Cheapflights users on 5/12. 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.
Tue 6/210:15 am
MDW
- STL
Nonstop1h 15m
Southwest
Deal found 5/12![Southwest logo]()
$59
This American Airlines deal was found by Cheapflights users on 5/12. 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.
Wed 7/2912:30 pm
ORD
- STL
Nonstop1h 23m
American Airlines
Deal found 5/12![American Airlines logo]()
$59
This Kiwi.com deal was found by Cheapflights users on 5/10. 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 6/171:29 pm
ORD
- STL
1 stop28h 01m
Frontier
Deal found 5/10![Frontier logo]()
$67
This Southwest deal was found by Cheapflights users on 5/12. 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.
Tue 6/210:30 am
ORD
- STL
1 stop7h 35m
Southwest
Deal found 5/12![Southwest logo]()
$69
This Kiwi.com deal was found by Cheapflights users on 5/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/212:27 pm
MDW
- STL
1 stop20h 28m
Frontier
Deal found 5/12![Frontier logo]()
$70
This Kiwi.com deal was found by Cheapflights users on 5/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/161:29 pm
ORD
- STL
1 stop19h 23m
Frontier
Deal found 5/12![Frontier logo]()
$70
This Delta deal was found by Cheapflights users on 5/12. 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 6/179:17 am
MDW
- STL
1 stop3h 52m
Delta
Deal found 5/12![Delta logo]()
$79
This Delta deal was found by Cheapflights users on 5/12. 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 6/178:52 am
ORD
- STL
1 stop4h 17m
Delta
Deal found 5/12![Delta logo]()
$79
This Kiwi.com deal was found by Cheapflights users on 5/11. 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.
Thu 6/186:55 am
ORD
- STL
1 stop10h 35m
Frontier
Deal found 5/11![Frontier logo]()
$81
This Kiwi.com deal was found by Cheapflights users on 5/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/116:55 am
ORD
- STL
1 stop10h 35m
Frontier
Deal found 5/12![Frontier logo]()
$83
This Kiwi.com deal was found by Cheapflights users on 5/11. 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.
Thu 6/46:00 am
MDW
- STL
1 stop11h 33m
Frontier
Deal found 5/11![Frontier logo]()
$84
This Kiwi.com deal was found by Cheapflights users on 5/11. 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.
Thu 6/46:55 am
ORD
- STL
1 stop10h 38m
Frontier
Deal found 5/11![Frontier logo]()
$84
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 May 13, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $250 (Priceline) |
One-way from | $59 (Southwest) |
Popular in | April |
Cheapest in | December |
Average price | $345 |
Good round-trip deal | $61 or less |
Good one-way deal | $177 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 May 13, 2026.
Use the filters below to find and compare flights from Illinois to St. Louis that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Fri 6/12
5:11 pm-11:56 pm
1 stop6h 45m
Lambert-St Louis
Tue 6/16
11:13 am-6:18 pm
1 stop7h 05m
$257
ChicagoSt. Louis
ORD - STL
ORDSTL
Chicago O'Hare Intl
Wed 6/10
8:52 am-1:09 pm
1 stop4h 17m
Lambert-St Louis
Thu 6/11
10:20 am-4:26 pm
1 stop6h 06m
$257
ChicagoSt. Louis
ORD - STL
ORDSTL
Chicago O'Hare Intl
Fri 6/12
6:22 pm-11:56 pm
1 stop5h 34m
Lambert-St Louis
Tue 6/16
6:21 am-11:31 am
1 stop5h 10m
$257
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Tue 6/9
6:00 am-5:30 pm
1 stop11h 30m
Lambert-St Louis
Tue 6/9
8:08 pm-11:09 am
2 stops15h 01m
$264
ChicagoSt. Louis
ORD - STL
ORDSTL
Chicago O'Hare Intl
Tue 6/9
8:52 am-4:46 pm
2 stops7h 54m
Lambert-St Louis
Wed 6/10
6:21 am-1:04 pm
2 stops6h 43m
$265
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Mon 6/8
9:35 pm-10:50 pm
Nonstop1h 15m
Lambert-St Louis
Mon 6/15
12:50 pm-5:05 pm
1 stop4h 15m
$274
Quickest round-trip
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Thu 6/4
11:00 am-12:10 pm
Nonstop1h 10m
Lambert-St Louis
Sun 6/7
5:50 am-6:55 am
Nonstop1h 05m
$275
ChicagoSt. Louis
MDW - STL
MDWSTL
Chicago Midway
Sat 5/30
9:05 am-4:25 pm
1 stop7h 20m
Lambert-St Louis
Mon 6/1
9:40 pm-10:45 pm
Nonstop1h 05m
$285
ChicagoSt. Louis
ORD - STL
ORDSTL
Chicago O'Hare Intl
Sat 6/6
1:44 pm-11:21 pm
2 stops9h 37m
Lambert-St Louis
Sat 6/13
11:18 am-5:27 pm
1 stop6h 09m
$289
ChicagoSt. Louis
ORD - STL
ORDSTL
Chicago O'Hare Intl
Mon 6/1
5:19 pm-9:09 pm
1 stop3h 50m
Lambert-St Louis
Tue 6/30
1:39 pm-8:32 pm
1 stop6h 53m
$297
Showing 1-10 of 47 resultsSorted by cheapest first
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
How far ahead should I book a flight from Illinois to St. Louis?
The price you pay for your flight from Illinois to St. Louis may vary depending on when you book. For the best chance of a lower fare, look to book 82 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest month to book a flight from Illinois to St. Louis?
Currently, September is the cheapest month in which you can book a flight from Illinois to St. Louis (average of $68). Flying from Illinois to St. Louis in January is currently the most expensive (average of $143). 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 May 13, 2026.
It’s typically best to fly out from Illinois to St. Louis at noon. Doing so could potentially save you 33% on the flight price compared to flying in the evening, 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 May 9, 2026.
Travelers seeking maximum savings on their Illinois to St. Louis flight should consider departing on Thursday at noon when fares are most often at their lowest. Sunday evenings 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 May 13, 2026.
The most flights from USIL to STL are scheduled on a Monday (80 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (53 on average).
How much does it cost to fly round-trip from Illinois to St. Louis?
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
Fenton
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Wentzville
Glencoe
Chesterfield
Alton
Farmington
Festus
Browse thousands of different options on Cheapflights for your next trip
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Alternative routes for Illinois to St. Louis
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Complete your trip
Complete your trip to St. Louis by adding a car rental and/or hotel reservation to your travel itinerary.
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Illinois and St. Louis flights
Browse other Illinois and St. Louis flight options. Last updated on May 13, 2026.
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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 May 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 May 13, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$77 | Average$423 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$124 | Average$342 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$155 | Average$393 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$165 | Average$238 | FlexibilityNo cancel fee | On-timeN/A |