$82+ Cheap flights from Ontario (ONT) to Missouri
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.
ONT — STL
Jun 14 — Jun 211
Round-trip
1 adult, Economy
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Find cheap flights from Ontario to Missouri with Cheapflights
1. Tell us where you want to go
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Cheapest flights from Ontario to MissouriExplore the most affordable flight options available from Ontario to Missouri. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 15, 2026.
Explore the most affordable flight options available from Ontario to Missouri. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 15, 2026.
This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/2510:50 am
ONT
- STL
1 stop6h 33m
Frontier
Tue 9/18:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Deal found 5/12![Frontier logo]()
$185
This Kiwi.com deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” 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 8/126:00 am
ONT
- STL
1 stop11h 23m
Frontier
Wed 8/268:08 pm
STL
- ONT
1 stop15h 57m
Frontier
Deal found 5/14![Frontier logo]()
$197
This Kiwi.com deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” 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 8/1210:49 am
ONT
- STL
1 stop6h 34m
Frontier
Mon 8/315:33 pm
STL
- ONT
2 stops32h 16m
Frontier
Deal found 5/14![Frontier logo]()
$200
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.
Tue 7/143:40 pm
ONT
- STL
2 stops25h 43m
Frontier
Tue 7/218:08 pm
STL
- ONT
1 stop15h 55m
Frontier
Deal found 5/10![Frontier logo]()
$206
This Expedia 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/93:34 pm
ONT
- STL
1 stop24h 34m
Frontier
Tue 6/238:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Deal found 5/12![Frontier logo]()
$210
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/26:00 am
ONT
- MCI
1 stop5h 49m
Frontier
Tue 6/91:45 pm
MCI
- ONT
1 stop12h 04m
Frontier
Deal found 5/11![Frontier logo]()
$210
This Kiwi.com deal was found by Cheapflights users on 5/13. 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 7/211:28 pm
ONT
- MCI
2 stops21h 27m
Frontier
Tue 7/281:45 pm
MCI
- ONT
1 stop22h 18m
Frontier
Deal found 5/13![Frontier logo]()
$214
This Kiwi.com deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” 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 8/1210:49 am
ONT
- STL
1 stop6h 34m
Frontier
Fri 8/285:33 pm
STL
- ONT
2 stops26h 19m
Frontier
Deal found 5/14![Frontier logo]()
$216
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.
Wed 8/1210:49 am
ONT
- MCI
1 stop24h 06m
Frontier
Wed 8/191:45 pm
MCI
- ONT
1 stop22h 20m
Frontier
Deal found 5/12![Frontier logo]()
$218
This Super.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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/223:40 pm
ONT
- STL
1 stop20h 27m
Frontier
Tue 7/287:03 pm
STL
- ONT
1 stop26h 50m
Frontier
Deal found 5/12![Frontier logo]()
$219
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/151:28 pm
ONT
- STL
1 stop22h 39m
Frontier
Tue 7/217:03 pm
STL
- ONT
1 stop26h 50m
Frontier
Deal found 5/11![Frontier logo]()
$220
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/81:28 pm
ONT
- MCI
1 stop21h 27m
Frontier
Tue 7/141:45 pm
MCI
- ONT
1 stop22h 18m
Frontier
Deal found 5/11![Frontier logo]()
$220
Best flights from Ontario to MissouriDiscover carefully curated flight deals from Ontario to Missouri that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 15, 2026.
Discover carefully curated flight deals from Ontario to Missouri that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 15, 2026.
This deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/178:07 am
ONT
- STL
1 stop7h 37m
Frontier
Mon 9/218:10 pm
STL
- ONT
1 stop5h 45m
Frontier
Deal found 5/14![Frontier logo]()
$216
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 6/97:13 pm
ONT
- COU
2 stops12h 53m
American Airlines
Mon 6/157:39 pm
COU
- ONT
1 stop6h 20m
American Airlines
Deal found 5/11![American Airlines logo]()
$353
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.
Wed 7/11:30 pm
ONT
- MCI
2 stops6h 30m
Southwest
Wed 7/86:00 am
MCI
- ONT
1 stop5h 15m
Southwest
Deal found 5/12![Southwest logo]()
$396
This United Airlines deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” 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 9/19:15 am
ONT
- SGF
1 stop7h 40m
United Airlines
Sat 9/55:30 am
SGF
- ONT
2 stops8h 42m
United Airlines
Deal found 5/14![United Airlines logo]()
$424
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 6/227:05 am
ONT
- SGF
1 stop9h 07m
Delta
Thu 7/24:08 pm
SGF
- ONT
1 stop7h 40m
Delta
Deal found 5/11![Delta logo]()
$429
This Alaska 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/152:05 pm
ONT
- MCI
1 stop7h 54m
Alaska Airlines
Sat 7/185:50 pm
MCI
- ONT
1 stop8h 02m
Alaska Airlines
Deal found 5/11![Alaska Airlines logo]()
$553
This Frontier deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” 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 6/66:00 am
ONT
- STL
1 stop11h 23m
Frontier
Tue 6/98:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Deal found 5/14![Frontier logo]()
$324
This KAYAK deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/177:57 pm
ONT
- UIN
2 stops15h 53m
Multiple Airlines
Sun 9/209:55 am
UIN
- ONT
2 stops12h 29m
Multiple Airlines
Deal found 5/14![Multiple Airlines logo]()
$659
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.
Sat 6/271:00 pm
ONT
- MCI
1 stop6h 12m
Delta
Mon 6/296:00 pm
MCI
- ONT
1 stop7h 49m
Delta
Deal found 5/10![Delta logo]()
$437
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.
Thu 7/910:25 am
ONT
- COU
1 stop6h 31m
American Airlines
Tue 7/145:19 pm
COU
- ONT
1 stop8h 40m
American Airlines
Deal found 5/12![American Airlines logo]()
$439
This Southwest deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” 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 6/1112:45 pm
ONT
- MCI
2 stops8h 35m
Southwest
Thu 6/189:15 pm
MCI
- ONT
1 stop4h 50m
Southwest
Deal found 5/14![Southwest logo]()
$442
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.
Thu 7/25:21 pm
ONT
- MCI
1 stop4h 57m
Delta
Mon 7/66:00 pm
MCI
- ONT
1 stop7h 49m
Delta
Deal found 5/11![Delta logo]()
$437
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/26:39 pm
ONT
- MCI
2 stops13h 50m
United Airlines
Sat 6/65:24 pm
MCI
- ONT
1 stop5h 22m
United Airlines
Deal found 5/12![United Airlines logo]()
$489
This Southwest deal was found by Cheapflights users on 5/13. 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.
Wed 6/104:35 pm
ONT
- MCI
1 stop4h 35m
Southwest
Wed 6/176:25 pm
MCI
- ONT
1 stop6h 10m
Southwest
Deal found 5/13![Southwest logo]()
$459
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/235:45 am
ONT
- SGF
1 stop8h 36m
United Airlines
Sat 9/265:30 am
SGF
- ONT
2 stops8h 42m
United Airlines
Deal found 5/11![United Airlines logo]()
$490
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.
Wed 8/56:00 am
ONT
- STL
1 stop5h 34m
Delta
Wed 8/57:35 pm
STL
- ONT
1 stop5h 59m
Delta
Deal found 5/11![Delta logo]()
$451
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.
Wed 8/59:40 am
ONT
- STL
1 stop6h 10m
Southwest
Sun 8/95:50 am
STL
- ONT
1 stop7h 55m
Southwest
Deal found 5/11![Southwest logo]()
$464
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.
Sun 8/2312:33 pm
ONT
- COU
1 stop7h 54m
American Airlines
Mon 8/315:17 pm
COU
- ONT
1 stop7h 41m
American Airlines
Deal found 5/11![American Airlines logo]()
$529
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/21:18 pm
ONT
- STL
1 stop5h 52m
United Airlines
Wed 6/35:10 am
STL
- ONT
2 stops9h 02m
United Airlines
Deal found 5/10![United Airlines logo]()
$502
This Delta deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” 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 6/295:21 pm
ONT
- STL
1 stop5h 22m
Delta
Thu 7/97:55 pm
STL
- ONT
1 stop5h 53m
Delta
Deal found 5/14![Delta logo]()
$465
This Southwest deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” 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 8/71:15 pm
ONT
- STL
2 stops7h 50m
Southwest
Mon 8/108:30 am
STL
- ONT
2 stops7h 30m
Southwest
Deal found 5/14![Southwest logo]()
$481
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/231:44 pm
ONT
- JLN
2 stops8h 09m
United Airlines
Sat 9/261:53 pm
JLN
- ONT
2 stops11h 06m
United Airlines
Deal found 5/11![United Airlines logo]()
$504
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.
Fri 7/316:00 am
ONT
- MCI
1 stop5h 57m
Delta
Sun 8/96:51 am
MCI
- ONT
1 stop7h 14m
Delta
Deal found 5/10![Delta logo]()
$467
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/210:05 am
ONT
- STL
2 stops8h 55m
Southwest
Mon 10/58:25 am
STL
- ONT
2 stops7h 35m
Southwest
Deal found 5/10![Southwest logo]()
$481
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/276:00 am
ONT
- JLN
2 stops9h 11m
United Airlines
Sun 11/16:02 pm
JLN
- ONT
1 stop28h 18m
United Airlines
Deal found 5/11![United Airlines logo]()
$510
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.
Wed 9/2312:00 pm
ONT
- SGF
1 stop8h 29m
Delta
Sun 9/273:30 pm
SGF
- ONT
1 stop8h 26m
Delta
Deal found 5/11![Delta logo]()
$479
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/156:10 am
ONT
- STL
2 stops8h 10m
Southwest
Mon 7/203:35 pm
STL
- ONT
2 stops8h 35m
Southwest
Deal found 5/10![Southwest logo]()
$487
This United Airlines deal was found by Cheapflights users on 5/13. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/15:00 am
ONT
- STL
1 stop16h 57m
United Airlines
Wed 8/198:00 am
STL
- ONT
2 stops14h 01m
United Airlines
Deal found 5/13![United Airlines logo]()
$514
This American Airlines deal was found by Cheapflights users on 5/13. 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.
Thu 6/1110:22 am
ONT
- COU
1 stop6h 47m
American Airlines
Wed 6/175:19 pm
COU
- ONT
1 stop7h 20m
American Airlines
Deal found 5/13![American Airlines logo]()
$687
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.
Thu 9/2410:59 pm
ONT
- SGF
1 stop10h 02m
Delta
Sun 9/2711:40 am
SGF
- ONT
1 stop8h 21m
Delta
Deal found 5/11![Delta logo]()
$479
Last-minute flights from Ontario to MissouriDiscover last-minute flight deals from Ontario to Missouri. Data last updated May 15, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Missouri. Data last updated May 15, 2026 and is based on user searches.
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.
Tue 5/266:00 am
ONT
- STL
1 stop11h 23m
Frontier
Sat 6/68:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Deal found 5/12![Frontier logo]()
$234
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/110:50 am
ONT
- MCI
1 stop24h 59m
Frontier
Tue 6/91:45 pm
MCI
- ONT
1 stop12h 04m
Frontier
Deal found 5/9![Frontier logo]()
$231
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/26:00 am
ONT
- MCI
1 stop5h 49m
Frontier
Tue 6/91:45 pm
MCI
- ONT
1 stop12h 04m
Frontier
Deal found 5/11![Frontier logo]()
$210
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/26:00 am
ONT
- STL
1 stop11h 23m
Frontier
Wed 6/38:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Deal found 5/11![Frontier logo]()
$230
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/26:00 am
ONT
- MCI
1 stop5h 49m
Frontier
Sun 6/72:34 pm
MCI
- ONT
1 stop11h 15m
Frontier
Deal found 5/11![Frontier logo]()
$230
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.
Tue 6/26:00 am
ONT
- MCI
1 stop5h 49m
Frontier
Sat 6/62:34 pm
MCI
- ONT
1 stop11h 15m
Frontier
Deal found 5/12![Frontier logo]()
$240
This CheapOair deal was found by Cheapflights users on 5/13. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/34:39 pm
ONT
- STL
1 stop25h 32m
Frontier
Sat 6/68:08 pm
STL
- ONT
1 stop15h 57m
Frontier
Deal found 5/13![Frontier logo]()
$224
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/411:51 am
ONT
- STL
1 stop6h 20m
Frontier
Mon 6/88:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Deal found 5/11![Frontier logo]()
$244
This Booking.com 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/83:30 pm
ONT
- STL
1 stop23h 35m
Frontier
Tue 6/98:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Deal found 5/9![Frontier logo]()
$231
This Expedia 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/93:34 pm
ONT
- STL
1 stop24h 34m
Frontier
Tue 6/238:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Deal found 5/12![Frontier logo]()
$210
This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/101:33 pm
ONT
- STL
1 stop22h 33m
Frontier
Wed 6/177:46 pm
STL
- ONT
1 stop21h 22m
Frontier
Deal found 5/12![Frontier logo]()
$226
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.
Wed 6/101:33 pm
ONT
- STL
1 stop22h 33m
Frontier
Mon 6/152:56 pm
STL
- ONT
1 stop6h 55m
Frontier
Deal found 5/10![Frontier logo]()
$232
One-way flights from Ontario to MissouriSearch for one-way flight options from Ontario to Missouri. Find affordable one-way fares based on user searches. Data last updated May 15, 2026.
Search for one-way flight options from Ontario to Missouri. Find affordable one-way fares based on user searches. Data last updated May 15, 2026.
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 6/26:00 am
ONT
- STL
1 stop11h 23m
Frontier
Deal found 5/12![Frontier logo]()
$82
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/110:50 am
ONT
- STL
1 stop6h 33m
Frontier
Deal found 5/11![Frontier logo]()
$105
This Super.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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/101:33 pm
ONT
- STL
1 stop22h 33m
Frontier
Deal found 5/12![Frontier logo]()
$106
This Super.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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/710:49 am
ONT
- MCI
1 stop24h 06m
Frontier
Deal found 5/11![Frontier logo]()
$106
This Super.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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/291:28 pm
ONT
- MCI
1 stop21h 27m
Frontier
Deal found 5/12![Frontier logo]()
$109
This Super.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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/301:33 pm
ONT
- STL
1 stop27h 18m
Frontier
Deal found 5/11![Frontier logo]()
$110
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.
Wed 7/83:40 pm
ONT
- MCI
1 stop19h 15m
Frontier
Deal found 5/10![Frontier logo]()
$111
This Super.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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/411:51 am
ONT
- STL
1 stop6h 20m
Frontier
Deal found 5/12![Frontier logo]()
$114
This Super.com deal was found by Cheapflights users on 5/13. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/266:00 am
ONT
- STL
1 stop11h 23m
Frontier
Deal found 5/13![Frontier logo]()
$116
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/223:40 pm
ONT
- MCI
1 stop19h 15m
Frontier
Deal found 5/11![Frontier logo]()
$116
This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/51:28 pm
ONT
- MCI
1 stop21h 27m
Frontier
Deal found 5/12![Frontier logo]()
$117
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/186:00 am
ONT
- MCI
1 stop4h 55m
Frontier
Deal found 5/11![Frontier logo]()
$119
Find flight deals from Ontario to Missouri
Keep the following information in mind while searching for Ontario to Missouri flight deals. Data was last updated May 15, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $185 (Trip.com) |
One-way from | $82 (Kiwi.com) |
Popular in | March |
Cheapest in | October |
Average price | $450 |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to Missouri 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 15, 2026.
Use the filters below to find and compare flights from Ontario to Missouri that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Thu 9/17
8:07 am-5:44 pm
1 stop7h 37m
Lambert-St Louis
Mon 9/21
8:10 pm-11:55 pm
1 stop5h 45m
$216
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Sat 6/6
6:00 am-7:23 pm
1 stop11h 23m
Lambert-St Louis
Tue 6/9
8:08 pm-11:49 pm
1 stop5h 41m
$324
OntarioColumbia
ONT - COU
ONTCOU
Ontario
Tue 6/9
7:13 pm-10:06 am
2 stops12h 53m
Columbia Regional
Mon 6/15
7:39 pm-11:59 pm
1 stop6h 20m
$353
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Wed 7/1
1:30 pm-10:00 pm
2 stops6h 30m
Kansas City
Wed 7/8
6:00 am-9:15 am
1 stop5h 15m
$396
OntarioSpringfield
ONT - SGF
ONTSGF
Ontario
Tue 9/1
9:15 am-6:55 pm
1 stop7h 40m
Springfield-Branson
Sat 9/5
5:30 am-12:12 pm
2 stops8h 42m
$424
OntarioSpringfield
ONT - SGF
ONTSGF
Ontario
Mon 6/22
7:05 am-6:12 pm
1 stop9h 07m
Springfield-Branson
Thu 7/2
4:08 pm-9:48 pm
1 stop7h 40m
$429
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Sat 6/27
1:00 pm-9:12 pm
1 stop6h 12m
Kansas City
Mon 6/29
6:00 pm-11:49 pm
1 stop7h 49m
$437
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Thu 7/2
5:21 pm-12:18 am
1 stop4h 57m
Kansas City
Mon 7/6
6:00 pm-11:49 pm
1 stop7h 49m
$437
OntarioColumbia
ONT - COU
ONTCOU
Ontario
Thu 7/9
10:25 am-6:56 pm
1 stop6h 31m
Columbia Regional
Tue 7/14
5:19 pm-11:59 pm
1 stop8h 40m
$439
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Thu 6/11
12:45 pm-11:20 pm
2 stops8h 35m
Kansas City
Thu 6/18
9:15 pm-12:05 am
1 stop4h 50m
$442
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Ontario to Missouri
Have a flexible travel schedule? Discover the best time to fly to Missouri from Ontario with our price prediction graph.
ONT-STL
ONT-MCI
ONT-SGF
ONT-COU
ONT-UIN
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 Ontario to Missouri
ONT-USMO
ONT-STL
ONT-MCI
ONT-SGF
ONT-COU
How far ahead should I book a flight from Ontario to Missouri?
Booking 77 days in advance of your planned departure date is, on average, the best time to get cheap flights from Ontario to Missouri. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
What is the cheapest month to book a flight from Ontario to Missouri?
Currently, September is the cheapest month in which you can book a flight from Ontario to Missouri (average of $71). Flying from Ontario to Missouri in March is currently the most expensive (average of $252). 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.
How much does it cost to fly round-trip from Ontario to Missouri?
Reviews of airlines servicing Missouri
Get insights into the airlines that provide service to Missouri. 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 Missouri. Reviews last updated May 15, 2026.
See what other customers who have flown with Southwest,Delta, andUnited Airlines from Ontario to Missouri have to say. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Boarding
8.1
Food
7.0
Comfort
8.0
Crew
8.6
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Boarding
8.1
Food
7.0
Comfort
8.0
Crew
8.6
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Boarding
8.1
Food
7.0
Comfort
8.0
Crew
8.6
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Boarding
8.1
Food
7.0
Comfort
8.0
Crew
8.6
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Boarding
8.1
Food
7.0
Comfort
8.0
Crew
8.6
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Boarding
8.1
Food
7.0
Comfort
8.0
Crew
8.6
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Related info for your journey
Find useful and relevant information for your journey from Ontario to Missouri. 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 Ontario to Missouri
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Missouri by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Ontario to Missouri by cabin class
Find flights from Ontario to Missouri, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Ontario and Missouri flights
Browse other Ontario and Missouri flight options. Last updated on May 15, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Ontario to Missouri flights
Consider these flights traveling from Ontario to Missouri.
Top 5 airlines flying from Ontario to Missouri
Discover the top 5 airlines that operate flights from Ontario to Missouri. 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 15, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$98 | Average$342 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$121 | Average$223 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$236 | Average$437 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$246 | Average$451 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$259 | Average$436 | FlexibilityNo cancel fee | On-time71% |