$59+ Cheap flights from Missouri 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 9/5. Fares are subject to change and may not be available on all flights or dates of travel.
STL — ORD
Sep 4 — Sep 111
Round-trip
1 adult, Economy
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Find cheap flights from Missouri 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 Missouri to IllinoisExplore the most affordable flight options available from Missouri to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 5, 2026.
Explore the most affordable flight options available from Missouri to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 5, 2026.
This Southwest deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 9/55:45 am -
Nonstop1h 05m
Sun 9/68:35 am -
Nonstop1h 20m
Deal found 8/3![Southwest logo]()
$117
This United Airlines deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/57:25 am -
Nonstop1h 36m
Sun 9/610:29 am -
Nonstop1h 33m
Deal found 8/4![United Airlines logo]()
$117
This American Airlines deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” 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 9/55:00 am -
Nonstop1h 24m
Sun 9/67:00 am -
Nonstop1h 24m
Deal found 8/1![American Airlines logo]()
$118
This United Airlines deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/296:00 am -
Nonstop1h 33m
Sat 9/58:40 am -
Nonstop1h 32m
Deal found 8/1![United Airlines logo]()
$134
This Frontier deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 8/314:23 pm -
1 stop6h 45m
Tue 9/19:20 am -
1 stop7h 11m
Deal found 7/31![Frontier logo]()
$142
This Frontier deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 9/142:29 pm -
1 stop9h 15m
Mon 9/216:25 am -
1 stop6h 45m
Deal found 7/31![Frontier logo]()
$143
This Southwest deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” 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 8/2910:10 am -
1 stop4h 10m
Sat 9/56:35 am -
Nonstop1h 10m
Deal found 8/1![Southwest logo]()
$144
This Frontier deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 10/110:20 am -
1 stop9h 15m
Tue 10/1311:06 am -
1 stop8h 09m
Deal found 7/31![Frontier logo]()
$147
This Frontier deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 9/1010:20 am -
1 stop9h 15m
Mon 9/218:55 pm -
1 stop14h 37m
Deal found 7/31![Frontier logo]()
$148
This Kiwi.com deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 8/2811:26 am -
1 stop5h 56m
Fri 9/46:17 pm -
1 stop21h 48m
Deal found 7/31![Frontier logo]()
$151
This Southwest deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 8/276:05 am -
Nonstop1h 05m
Mon 8/315:50 pm -
Nonstop1h 15m
Deal found 8/4![Southwest logo]()
$151
This United Airlines deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 8/317:25 am -
Nonstop1h 36m
Mon 9/77:05 am -
Nonstop1h 34m
Deal found 8/3![United Airlines logo]()
$151
Best flights from Missouri to IllinoisDiscover carefully curated flight deals from Missouri to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 5, 2026.
Discover carefully curated flight deals from Missouri to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 5, 2026.
This Southwest deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” 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 8/295:45 am -
Nonstop1h 05m
Sat 9/510:05 am -
2 stops6h 45m
Deal found 8/1![Southwest logo]()
$149
This Delta deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 9/55:34 pm -
1 stop4h 13m
Sun 9/66:00 am -
1 stop4h 23m
Deal found 8/4![Delta logo]()
$157
This United Airlines deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 8/2812:59 pm -
Nonstop1h 31m
Mon 8/3110:29 am -
Nonstop1h 33m
Deal found 8/4![United Airlines logo]()
$200
This CheapOair deal was found by Cheapflights users on 8/2. Clicking the “Pick Dates” 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.
Mon 8/244:47 pm -
1 stop25h 03m
Wed 8/266:45 pm -
1 stop21h 17m
Deal found 8/2![Frontier logo]()
$202
This American Airlines deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 9/17:39 pm -
1 stop4h 29m
Tue 9/86:45 pm -
1 stop5h 50m
Deal found 8/4![American Airlines logo]()
$289
This Southwest deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 9/16:30 am -
Nonstop1h 05m
Wed 9/22:00 pm -
Nonstop1h 10m
Deal found 7/31![Southwest logo]()
$151
This Delta deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” 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 8/295:34 pm -
1 stop4h 13m
Sun 9/66:00 am -
1 stop4h 23m
Deal found 8/1![Delta logo]()
$164
This Southwest deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 8/266:30 am -
Nonstop1h 05m
Thu 8/273:10 pm -
Nonstop1h 10m
Deal found 8/4![Southwest logo]()
$151
This Southwest deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 10/1210:00 pm -
Nonstop1h 05m
Thu 10/157:50 am -
Nonstop1h 10m
Deal found 8/4![Southwest logo]()
$151
This Delta deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 10/66:47 am -
1 stop6h 12m
Wed 10/77:10 am -
1 stop6h 43m
Deal found 8/3![Delta logo]()
$171
This Southwest deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 9/193:00 pm -
Nonstop1h 10m
Mon 9/217:55 am -
Nonstop1h 20m
Deal found 8/4![Southwest logo]()
$151
This Delta deal was found by Cheapflights users on 8/2. Clicking the “Pick Dates” 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 8/266:30 am -
1 stop4h 12m
Wed 9/21:59 pm -
1 stop6h 43m
Deal found 8/2![Delta logo]()
$171
This United Airlines deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” 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 9/238:00 am -
Nonstop1h 34m
Thu 9/242:12 pm -
Nonstop1h 31m
Deal found 8/1![United Airlines logo]()
$221
This Delta deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” 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 12/102:18 pm -
1 stop6h 07m
Wed 1/139:30 am -
1 stop5h 01m
Deal found 8/5![Delta logo]()
$171
This Southwest deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 10/65:50 am -
Nonstop1h 05m
Wed 10/74:45 pm -
1 stop5h 40m
Deal found 8/3![Southwest logo]()
$161
This United Airlines deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 9/223:12 pm -
Nonstop1h 48m
Sat 9/269:00 am -
Nonstop1h 39m
Deal found 8/4![United Airlines logo]()
$226
This Delta deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 8/276:30 am -
1 stop4h 12m
Mon 8/311:59 pm -
1 stop6h 43m
Deal found 8/4![Delta logo]()
$171
This Southwest deal was found by Cheapflights users on 8/2. Clicking the “Pick Dates” 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 9/1610:45 am -
Nonstop1h 05m
Wed 9/239:00 am -
1 stop4h 55m
Deal found 8/2![Southwest logo]()
$161
This Delta deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 10/66:47 am -
1 stop6h 12m
Thu 10/81:55 pm -
1 stop6h 56m
Deal found 8/3![Delta logo]()
$171
This Kiwi.com deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 8/146:17 pm -
1 stop14h 40m
Fri 8/217:58 pm -
2 stops20h 07m
Deal found 7/31![Frontier logo]()
$284
This United Airlines deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 9/106:37 pm -
Nonstop2h 00m
Sat 9/128:00 pm -
Nonstop2h 02m
Deal found 8/4![United Airlines logo]()
$236
This Southwest deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” 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 8/2612:50 pm -
Nonstop1h 05m
Sat 8/299:55 am -
2 stops6h 45m
Deal found 8/1![Southwest logo]()
$166
This United Airlines deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/306:24 am -
Nonstop1h 58m
Wed 11/410:45 am -
Nonstop1h 52m
Deal found 8/1![United Airlines logo]()
$241
This Southwest deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 10/610:20 am -
2 stops5h 50m
Thu 10/810:05 pm -
Nonstop1h 10m
Deal found 8/3![Southwest logo]()
$166
This United Airlines deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” 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 9/257:32 am -
Nonstop1h 58m
Sun 9/2710:15 am -
Nonstop1h 54m
Deal found 8/5![United Airlines logo]()
$241
This Delta deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” 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 9/26:30 am -
1 stop6h 38m
Fri 9/41:59 pm -
1 stop6h 43m
Deal found 8/5![Delta logo]()
$220
This United Airlines deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/1011:19 am -
Nonstop1h 43m
Mon 10/129:20 pm -
Nonstop1h 35m
Deal found 8/1![United Airlines logo]()
$249
This American Airlines deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 9/175:13 am -
Nonstop1h 46m
Thu 9/173:50 pm -
1 stop6h 06m
Deal found 8/4![American Airlines logo]()
$407
This Delta deal was found by Cheapflights users on 8/2. Clicking the “Pick Dates” 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 8/262:10 pm -
1 stop6h 20m
Fri 8/281:59 pm -
1 stop3h 39m
Deal found 8/2![Delta logo]()
$220
This United Airlines deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 9/116:15 am -
Nonstop1h 39m
Wed 9/309:00 am -
Nonstop1h 39m
Deal found 8/3![United Airlines logo]()
$249
Last-minute flights from Missouri to IllinoisDiscover last-minute flight deals from Missouri to Illinois. Data last updated August 5, 2026 and is based on user searches.
Discover last-minute flight deals from Missouri to Illinois. Data last updated August 5, 2026 and is based on user searches.
This Southwest deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 8/276:05 am -
Nonstop1h 05m
Mon 8/315:50 pm -
Nonstop1h 15m
Deal found 8/4![Southwest logo]()
$151
This Kiwi.com deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 8/2811:26 am -
1 stop5h 56m
Fri 9/46:17 pm -
1 stop21h 48m
Deal found 7/31![Frontier logo]()
$151
This United Airlines deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/296:00 am -
Nonstop1h 33m
Sat 9/58:40 am -
Nonstop1h 32m
Deal found 8/1![United Airlines logo]()
$134
This Southwest deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” 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 8/2910:10 am -
1 stop4h 10m
Sat 9/56:35 am -
Nonstop1h 10m
Deal found 8/1![Southwest logo]()
$144
This Frontier deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 8/314:23 pm -
1 stop6h 45m
Tue 9/19:20 am -
1 stop7h 11m
Deal found 7/31![Frontier logo]()
$142
This United Airlines deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 8/317:25 am -
Nonstop1h 36m
Mon 9/77:05 am -
Nonstop1h 34m
Deal found 8/3![United Airlines logo]()
$151
This Southwest deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 9/55:45 am -
Nonstop1h 05m
Sun 9/68:35 am -
Nonstop1h 20m
Deal found 8/3![Southwest logo]()
$117
This United Airlines deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/57:25 am -
Nonstop1h 36m
Sun 9/610:29 am -
Nonstop1h 33m
Deal found 8/4![United Airlines logo]()
$117
This American Airlines deal was found by Cheapflights users on 8/1. Clicking the “Pick Dates” 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 9/55:00 am -
Nonstop1h 24m
Sun 9/67:00 am -
Nonstop1h 24m
Deal found 8/1![American Airlines logo]()
$118
This Frontier deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 9/1010:20 am -
1 stop9h 15m
Mon 9/218:55 pm -
1 stop14h 37m
Deal found 7/31![Frontier logo]()
$148
This Frontier deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 9/142:29 pm -
1 stop9h 15m
Mon 9/216:25 am -
1 stop6h 45m
Deal found 7/31![Frontier logo]()
$143
This Frontier deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 9/1710:20 am -
1 stop9h 15m
Sat 9/196:30 am -
1 stop12h 47m
Deal found 8/3![Frontier logo]()
$147
One-way flights from Missouri to IllinoisSearch for one-way flight options from Missouri to Illinois. Find affordable one-way fares based on user searches. Data last updated August 5, 2026.
Search for one-way flight options from Missouri to Illinois. Find affordable one-way fares based on user searches. Data last updated August 5, 2026.
This Southwest deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 9/55:45 am -
Nonstop1h 05m
Deal found 8/3![Southwest logo]()
$59
This American Airlines deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 9/58:06 pm -
Nonstop1h 33m
Deal found 8/3![American Airlines logo]()
$59
This Kiwi.com deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 8/3111:26 am -
1 stop5h 56m
Deal found 7/31![Frontier logo]()
$63
This Kiwi.com deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 8/2811:26 am -
1 stop5h 56m
Deal found 7/31![Frontier logo]()
$67
This Kiwi.com deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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.
Sat 8/295:00 pm -
1 stop24h 22m
Deal found 7/31![Frontier logo]()
$68
This Frontier deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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 8/314:23 pm -
1 stop6h 45m
Deal found 7/31![Frontier logo]()
$71
This Kiwi.com deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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.
Sat 9/55:00 pm -
1 stop24h 22m
Deal found 8/3![Frontier logo]()
$72
This Kiwi.com deal was found by Cheapflights users on 8/2. Clicking the “Pick Dates” 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 9/411:26 am -
1 stop5h 56m
Deal found 8/2![Frontier logo]()
$73
This Southwest deal was found by Cheapflights users on 8/4. Clicking the “Pick Dates” 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 8/312:20 pm -
Nonstop1h 05m
Deal found 8/4![Southwest logo]()
$76
This United Airlines deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/198:00 am -
Nonstop1h 34m
Deal found 8/3![United Airlines logo]()
$76
This Frontier deal was found by Cheapflights users on 8/3. Clicking the “Pick Dates” 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 10/52:29 pm -
1 stop9h 15m
Deal found 8/3![Frontier logo]()
$77
This Priceline deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/110:20 am -
1 stop9h 15m
Deal found 7/31![Frontier logo]()
$77
Find flight deals from Missouri to Illinois
Keep the following information in mind while searching for Missouri to Illinois flight deals. Data was last updated August 5, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $117 (Southwest) |
One-way from | $59 (Southwest) |
Popular in | July |
Cheapest in | November |
Average price | $353 |
Good round-trip deal | $170 or less |
Good one-way deal | $69 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Missouri 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 August 5, 2026.
Use the filters below to find and compare flights from Missouri to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Sat 8/29
5:45 am-6:50 am
Nonstop1h 05m
Chicago Midway
Sat 9/5
10:05 am-4:50 pm
2 stops6h 45m
$149
Quickest round-trip
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Tue 9/1
6:30 am-7:35 am
Nonstop1h 05m
Chicago Midway
Wed 9/2
2:00 pm-3:10 pm
Nonstop1h 10m
$151
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Wed 8/26
6:30 am-7:35 am
Nonstop1h 05m
Chicago Midway
Thu 8/27
3:10 pm-4:20 pm
Nonstop1h 10m
$151
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Mon 10/12
10:00 pm-11:05 pm
Nonstop1h 05m
Chicago Midway
Thu 10/15
7:50 am-9:00 am
Nonstop1h 10m
$151
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Sat 9/19
3:00 pm-4:10 pm
Nonstop1h 10m
Chicago Midway
Mon 9/21
7:55 am-9:15 am
Nonstop1h 20m
$151
St. LouisChicago
STL - ORD
STLORD
Lambert-St Louis
Sat 9/5
5:34 pm-9:47 pm
1 stop4h 13m
Chicago O'Hare Intl
Sun 9/6
6:00 am-10:23 am
1 stop4h 23m
$157
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Tue 10/6
5:50 am-6:55 am
Nonstop1h 05m
Chicago Midway
Wed 10/7
4:45 pm-10:25 pm
1 stop5h 40m
$161
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Wed 9/16
10:45 am-11:50 am
Nonstop1h 05m
Chicago Midway
Wed 9/23
9:00 am-1:55 pm
1 stop4h 55m
$161
St. LouisChicago
STL - ORD
STLORD
Lambert-St Louis
Sat 8/29
5:34 pm-9:47 pm
1 stop4h 13m
Chicago O'Hare Intl
Sun 9/6
6:00 am-10:23 am
1 stop4h 23m
$164
St. LouisChicago
STL - MDW
STLMDW
Lambert-St Louis
Wed 8/26
12:50 pm-1:55 pm
Nonstop1h 05m
Chicago Midway
Sat 8/29
9:55 am-4:40 pm
2 stops6h 45m
$166
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Missouri to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from Missouri with our price prediction graph.
MCI-STL
STL-MDW
STL-ORD
MCI-MLI
COU-ORD
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Missouri to Illinois
USMO-USIL
MCI-STL
STL-MDW
STL-ORD
MCI-MLI
What is the cheapest month to book a flight from Missouri to Illinois?
Currently, December is the cheapest month in which you can book a flight from Missouri to Illinois (average of $280). Flying from Missouri to Illinois in July is currently the most expensive (average of $384). 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 MO to IL?
Find hourly flight availability from Missouri 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 August 5, 2026.
When flying from Missouri 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 35% versus a flight in the evening.
Weekly flight availability from Missouri to Illinois
Explore weekly flight availability from Missouri 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 August 5, 2026.
The most flights from USMO to USIL are scheduled on a Monday (76 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (23 on average).
How much does it cost to fly round-trip from Missouri to Illinois?
Airfare is below average for this route at the moment.
Missouri to Illinois flights typically cost between $246 and $404 in September.The cheapest round-trip price found within the last 5 days was $117 on United Airlines (Sep 5-Sep 6).
How far ahead should I book a flight from Missouri to Illinois?
The price you pay for your flight from Missouri to Illinois may vary depending on when you book. For the best chance of a lower fare, look to book 83 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest day to fly from Missouri to Illinois?
Use this chart to determine the cheapest time to fly round-trip from Missouri to Illinois. Price data was last updated on August 1, 2026.
Travelers seeking maximum savings on their Missouri to Illinois flight should consider departing on Friday at noon when fares are most often at their lowest. Monday evenings flights should be avoided if possible as fares are typically the most expensive at this time.
Reviews of airlines servicing Illinois
Get insights into the airlines that provide service to Illinois. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Illinois. Reviews last updated August 5, 2026.
Read reviews from past customers who have flown Southwest,Contour, andUnited Airlines from Missouri to Illinois. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Comfort
8.0
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Comfort
8.0
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Comfort
8.0
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Comfort
8.0
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Comfort
8.0
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Comfort
8.0
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Overall
8.0
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Related info for your journey
Find useful and relevant information for your journey from Missouri 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 Missouri to Illinois
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Illinois by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Missouri to Illinois by cabin class
Find flights from Missouri to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Missouri and Illinois flights
Browse other Missouri and Illinois flight options. Last updated on August 5, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Find a return flight route from Illinois
Find the right flight back to Missouri after your stay in Illinois
Missouri to Illinois flights
Consider these flights traveling from Missouri to Illinois.
Top 5 airlines flying from Missouri to Illinois
Discover the top 5 airlines that operate flights from Missouri 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 August 5, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$62 | Average$164 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$97 | Average$387 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$117 | Average$384 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$158 | Average$182 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$181 | Average$473 | FlexibilityNo cancel fee | On-time63% |