$72+ 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 4/7. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — STL
Apr 10 — Apr 171
Round-trip
1 adult, Economy
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Find cheap flights from Ontario to Missouri with Cheapflights
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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 March 11, 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 March 11, 2026.
This Frontier deal was found by Cheapflights users on 3/8. 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.
Thu 4/1611:47 am
ONT
- STL
1 stop7h 13m
Frontier
Mon 4/203:21 pm
STL
- ONT
1 stop10h 22m
Frontier
Deal found 3/8![Frontier logo]()
$190
This Frontier deal was found by Cheapflights users on 3/9. 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.
Thu 4/3012:59 am
ONT
- MCI
1 stop10h 31m
Frontier
Mon 5/112:15 pm
MCI
- ONT
1 stop11h 40m
Frontier
Deal found 3/9![Frontier logo]()
$190
This Frontier deal was found by Cheapflights users on 3/8. 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.
Fri 4/175:33 pm
ONT
- MCI
1 stop18h 33m
Frontier
Sat 4/252:51 pm
MCI
- ONT
1 stop11h 04m
Frontier
Deal found 3/8![Frontier logo]()
$191
This Booking.com deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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 4/2912:59 am
ONT
- STL
1 stop16h 22m
Frontier
Sun 5/39:55 pm
STL
- ONT
1 stop12h 09m
Frontier
Deal found 3/6![Frontier logo]()
$192
This Mytrip deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/242:23 pm
ONT
- STL
1 stop18h 56m
Frontier
Wed 3/258:12 pm
STL
- ONT
1 stop5h 47m
Frontier
Deal found 3/6![Frontier logo]()
$196
This Booking.com deal was found by Cheapflights users on 3/9. 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.
Thu 4/1611:47 am
ONT
- STL
1 stop7h 13m
Frontier
Sun 4/199:55 pm
STL
- ONT
1 stop24h 09m
Frontier
Deal found 3/9![Frontier logo]()
$197
This CheapOair deal was found by Cheapflights users on 3/9. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/2311:47 am
ONT
- STL
1 stop7h 13m
Frontier
Fri 4/249:58 pm
STL
- ONT
1 stop14h 46m
Frontier
Deal found 3/9![Frontier logo]()
$201
This CheapOair deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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.
Fri 5/85:33 pm
ONT
- MCI
1 stop18h 33m
Frontier
Mon 5/112:15 pm
MCI
- ONT
1 stop11h 40m
Frontier
Deal found 3/6![Frontier logo]()
$201
This Booking.com deal was found by Cheapflights users on 3/10. 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 4/157:44 pm
ONT
- STL
1 stop23h 16m
Frontier
Mon 4/209:55 pm
STL
- ONT
1 stop22h 54m
Frontier
Deal found 3/10![Frontier logo]()
$203
This Booking.com deal was found by Cheapflights users on 3/10. 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.
Thu 5/711:44 am
ONT
- STL
1 stop7h 16m
Frontier
Sun 5/109:55 pm
STL
- ONT
1 stop12h 09m
Frontier
Deal found 3/10![Frontier logo]()
$207
This Frontier deal was found by Cheapflights users on 3/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/86:15 am
ONT
- STL
1 stop5h 57m
Frontier
Sun 5/109:55 pm
STL
- ONT
1 stop12h 09m
Frontier
Deal found 3/7![Frontier logo]()
$211
This Frontier deal was found by Cheapflights users on 3/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1712:59 am
ONT
- MCI
1 stop11h 07m
Frontier
Sat 4/252:51 pm
MCI
- ONT
1 stop11h 04m
Frontier
Deal found 3/7![Frontier logo]()
$211
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 March 11, 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 March 11, 2026.
This American Airlines deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/247:35 pm
ONT
- COU
2 stops12h 11m
American Airlines
Sun 4/267:43 pm
COU
- ONT
1 stop6h 03m
American Airlines
Deal found 3/6![American Airlines logo]()
$304
This United Airlines deal was found by Cheapflights users on 3/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/221:34 pm
ONT
- SGF
1 stop5h 27m
United Airlines
Tue 4/283:10 pm
SGF
- ONT
1 stop9h 21m
United Airlines
Deal found 3/7![United Airlines logo]()
$309
This Delta deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/111:20 pm
ONT
- STL
1 stop6h 11m
Delta
Wed 4/156:45 pm
STL
- ONT
1 stop6h 59m
Delta
Deal found 3/6![Delta logo]()
$317
This Alaska Airlines deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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 4/297:00 am
ONT
- MCI
1 stop7h 17m
Alaska Airlines
Sat 5/25:11 pm
MCI
- ONT
1 stop8h 37m
Alaska Airlines
Deal found 3/6![Alaska Airlines logo]()
$317
This Southwest deal was found by Cheapflights users on 3/8. 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 4/171:55 pm
ONT
- MCI
2 stops7h 30m
Southwest
Sat 4/255:35 am
MCI
- ONT
2 stops7h 30m
Southwest
Deal found 3/8![Southwest logo]()
$392
This United Airlines deal was found by Cheapflights users on 3/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/311:34 pm
ONT
- MCI
1 stop5h 00m
United Airlines
Sat 4/47:00 am
MCI
- ONT
1 stop7h 20m
United Airlines
Deal found 3/10![United Airlines logo]()
$317
This Delta deal was found by Cheapflights users on 3/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/191:35 pm
ONT
- MCI
1 stop8h 00m
Delta
Thu 5/287:40 pm
MCI
- ONT
1 stop5h 54m
Delta
Deal found 3/7![Delta logo]()
$336
This Alaska Airlines deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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.
Sat 4/186:00 am
ONT
- MCI
1 stop15h 59m
Alaska Airlines
Tue 4/216:15 am
MCI
- ONT
1 stop19h 44m
Alaska Airlines
Deal found 3/6![Alaska Airlines logo]()
$370
This Delta deal was found by Cheapflights users on 3/10. 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.
Wed 4/15:09 pm
ONT
- MCI
1 stop5h 37m
Delta
Tue 4/78:11 pm
MCI
- ONT
1 stop5h 40m
Delta
Deal found 3/10![Delta logo]()
$368
This Alaska Airlines deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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.
Fri 5/157:00 am
ONT
- STL
1 stop7h 37m
Alaska Airlines
Tue 5/195:33 pm
STL
- ONT
1 stop8h 23m
Alaska Airlines
Deal found 3/6![Alaska Airlines logo]()
$387
This United Airlines deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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 4/187:00 am
ONT
- SGF
1 stop8h 24m
United Airlines
Tue 4/212:52 pm
SGF
- ONT
1 stop8h 58m
United Airlines
Deal found 3/6![United Airlines logo]()
$389
This Southwest deal was found by Cheapflights users on 3/8. 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 8/510:55 am
ONT
- STL
1 stop5h 50m
Southwest
Sun 8/98:25 am
STL
- ONT
2 stops7h 45m
Southwest
Deal found 3/8![Southwest logo]()
$462
This Delta deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/126:00 am
ONT
- STL
1 stop5h 32m
Delta
Fri 5/157:59 pm
STL
- ONT
1 stop5h 35m
Delta
Deal found 3/6![Delta logo]()
$387
This Alaska Airlines deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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 4/297:00 am
ONT
- MCI
1 stop7h 17m
Alaska Airlines
Fri 5/15:11 pm
MCI
- ONT
1 stop8h 37m
Alaska Airlines
Deal found 3/6![Alaska Airlines logo]()
$392
This United Airlines deal was found by Cheapflights users on 3/10. 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.
Sat 4/181:34 pm
ONT
- COU
1 stop5h 29m
United Airlines
Wed 4/223:23 pm
COU
- ONT
1 stop9h 08m
United Airlines
Deal found 3/10![United Airlines logo]()
$398
This Delta deal was found by Cheapflights users on 3/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/110:25 pm
ONT
- STL
1 stop8h 40m
Delta
Mon 4/66:12 pm
STL
- ONT
1 stop7h 39m
Delta
Deal found 3/9![Delta logo]()
$396
This Alaska Airlines deal was found by Cheapflights users on 3/9. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/147:00 am
ONT
- MCI
1 stop7h 56m
Alaska Airlines
Wed 4/156:15 am
MCI
- ONT
1 stop19h 44m
Alaska Airlines
Deal found 3/9![Alaska Airlines logo]()
$402
This United Airlines deal was found by Cheapflights users on 3/7. Clicking the “Pick Dates” 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 4/146:00 am
ONT
- MCI
2 stops8h 16m
United Airlines
Wed 4/155:18 pm
MCI
- ONT
1 stop5h 18m
United Airlines
Deal found 3/7![United Airlines logo]()
$402
This United Airlines deal was found by Cheapflights users on 3/8. 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.
Tue 7/281:18 pm
ONT
- COU
1 stop5h 21m
United Airlines
Tue 8/49:14 am
COU
- ONT
1 stop5h 33m
United Airlines
Deal found 3/8![United Airlines logo]()
$403
This Delta deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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 3/275:09 pm
ONT
- STL
1 stop5h 12m
Delta
Tue 3/317:15 am
STL
- ONT
1 stop7h 08m
Delta
Deal found 3/6![Delta logo]()
$406
This Alaska Airlines deal was found by Cheapflights users on 3/10. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/107:00 am
ONT
- MCI
1 stop7h 17m
Alaska Airlines
Wed 5/135:52 pm
MCI
- ONT
1 stop8h 04m
Alaska Airlines
Deal found 3/10![Alaska Airlines logo]()
$408
This United Airlines deal was found by Cheapflights users on 3/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/151:34 pm
ONT
- COU
1 stop5h 29m
United Airlines
Tue 4/213:23 pm
COU
- ONT
1 stop9h 08m
United Airlines
Deal found 3/7![United Airlines logo]()
$403
This Delta deal was found by Cheapflights users on 3/9. 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.
Mon 3/305:09 pm
ONT
- STL
1 stop5h 12m
Delta
Fri 4/37:15 am
STL
- ONT
1 stop7h 08m
Delta
Deal found 3/9![Delta logo]()
$406
This Alaska Airlines deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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.
Mon 5/113:26 pm
ONT
- STL
1 stop30h 33m
Alaska Airlines
Wed 5/137:41 pm
STL
- ONT
1 stop30h 17m
Alaska Airlines
Deal found 3/6![Alaska Airlines logo]()
$443
This United Airlines deal was found by Cheapflights users on 3/11. 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.
Fri 4/101:43 pm
ONT
- COU
1 stop5h 20m
United Airlines
Sat 4/183:23 pm
COU
- ONT
1 stop9h 08m
United Airlines
Deal found 3/11![United Airlines logo]()
$423
This Alaska Airlines deal was found by Cheapflights users on 3/8. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/2012:00 pm
ONT
- STL
1 stop9h 59m
Alaska Airlines
Sun 8/236:20 pm
STL
- ONT
1 stop7h 39m
Alaska Airlines
Deal found 3/8![Alaska Airlines logo]()
$457
This Delta deal was found by Cheapflights users on 3/11. 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.
Sun 5/174:57 pm
ONT
- STL
1 stop5h 33m
Delta
Mon 5/187:59 pm
STL
- ONT
1 stop5h 35m
Delta
Deal found 3/11![Delta logo]()
$459
This United Airlines deal was found by Cheapflights users on 3/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/21:40 pm
ONT
- COU
1 stop5h 09m
United Airlines
Sat 5/911:30 am
COU
- ONT
1 stop8h 31m
United Airlines
Deal found 3/9![United Airlines logo]()
$423
This United Airlines deal was found by Cheapflights users on 3/11. 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 4/151:34 pm
ONT
- COU
1 stop5h 29m
United Airlines
Sat 4/183:23 pm
COU
- ONT
1 stop9h 08m
United Airlines
Deal found 3/11![United Airlines logo]()
$423
This United Airlines deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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 5/205:00 am
ONT
- STL
1 stop6h 13m
United Airlines
Sat 5/239:06 am
STL
- ONT
1 stop5h 41m
United Airlines
Deal found 3/6![United Airlines logo]()
$448
Last-minute flights from Ontario to MissouriDiscover last-minute flight deals from Ontario to Missouri. Data last updated March 11, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Missouri. Data last updated March 11, 2026 and is based on user searches.
This Mytrip deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/242:23 pm
ONT
- STL
1 stop18h 56m
Frontier
Wed 3/258:12 pm
STL
- ONT
1 stop5h 47m
Frontier
Deal found 3/6![Frontier logo]()
$196
This Frontier deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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 4/210:50 am
ONT
- STL
1 stop8h 27m
Frontier
Wed 4/88:16 pm
STL
- ONT
1 stop5h 40m
Frontier
Deal found 3/6![Frontier logo]()
$214
This Kiwi.com deal was found by Cheapflights users on 3/10. 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 4/76:20 am
ONT
- MCI
1 stop11h 38m
Multiple Airlines
Tue 4/146:04 pm
MCI
- ONT
1 stop18h 40m
Multiple Airlines
Deal found 3/10![Multiple Airlines logo]()
$218
This Booking.com deal was found by Cheapflights users on 3/10. 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 4/157:44 pm
ONT
- STL
1 stop23h 16m
Frontier
Mon 4/209:55 pm
STL
- ONT
1 stop22h 54m
Frontier
Deal found 3/10![Frontier logo]()
$203
This Frontier deal was found by Cheapflights users on 3/8. 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.
Thu 4/1611:47 am
ONT
- STL
1 stop7h 13m
Frontier
Mon 4/203:21 pm
STL
- ONT
1 stop10h 22m
Frontier
Deal found 3/8![Frontier logo]()
$190
This Booking.com deal was found by Cheapflights users on 3/9. 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.
Thu 4/1611:47 am
ONT
- STL
1 stop7h 13m
Frontier
Sun 4/199:55 pm
STL
- ONT
1 stop24h 09m
Frontier
Deal found 3/9![Frontier logo]()
$197
This Frontier deal was found by Cheapflights users on 3/8. 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.
Fri 4/175:33 pm
ONT
- MCI
1 stop18h 33m
Frontier
Sat 4/252:51 pm
MCI
- ONT
1 stop11h 04m
Frontier
Deal found 3/8![Frontier logo]()
$191
This Expedia deal was found by Cheapflights users on 3/9. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1712:59 am
ONT
- STL
1 stop16h 33m
Frontier
Fri 4/248:06 pm
STL
- ONT
1 stop5h 49m
Frontier
Deal found 3/9![Frontier logo]()
$211
This Frontier deal was found by Cheapflights users on 3/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1712:59 am
ONT
- MCI
1 stop11h 07m
Frontier
Sat 4/252:51 pm
MCI
- ONT
1 stop11h 04m
Frontier
Deal found 3/7![Frontier logo]()
$211
This CheapOair deal was found by Cheapflights users on 3/9. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/2311:47 am
ONT
- STL
1 stop7h 13m
Frontier
Fri 4/249:58 pm
STL
- ONT
1 stop14h 46m
Frontier
Deal found 3/9![Frontier logo]()
$201
This Booking.com deal was found by Cheapflights users on 3/10. 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.
Thu 4/2311:47 am
ONT
- STL
1 stop7h 13m
Frontier
Mon 4/279:55 pm
STL
- ONT
1 stop22h 54m
Frontier
Deal found 3/10![Frontier logo]()
$212
This Booking.com deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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 4/2912:59 am
ONT
- STL
1 stop16h 22m
Frontier
Sun 5/39:55 pm
STL
- ONT
1 stop12h 09m
Frontier
Deal found 3/6![Frontier logo]()
$192
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 March 11, 2026.
Search for one-way flight options from Ontario to Missouri. Find affordable one-way fares based on user searches. Data last updated March 11, 2026.
This Trip.com deal was found by Cheapflights users on 3/5. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/76:20 am
ONT
- MCI
1 stop11h 38m
Frontier
Deal found 3/5![Frontier logo]()
$72
This Trip.com deal was found by Cheapflights users on 3/5. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/112:59 am
ONT
- MCI
1 stop11h 07m
Frontier
Deal found 3/5![Frontier logo]()
$73
This Frontier deal was found by Cheapflights users on 3/9. 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.
Fri 4/1711:44 am
ONT
- STL
1 stop7h 26m
Frontier
Deal found 3/9![Frontier logo]()
$95
This Trip.com deal was found by Cheapflights users on 3/5. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/212:59 am
ONT
- MCI
1 stop10h 31m
Frontier
Deal found 3/5![Frontier logo]()
$95
This Super.com deal was found by Cheapflights users on 3/8. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/242:23 pm
ONT
- STL
1 stop18h 56m
Frontier
Deal found 3/8![Frontier logo]()
$99
This Trip.com deal was found by Cheapflights users on 3/10. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/1712:59 am
ONT
- MCI
1 stop11h 07m
Frontier
Deal found 3/10![Frontier logo]()
$100
This Booking.com deal was found by Cheapflights users on 3/8. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/76:20 am
ONT
- STL
1 stop25h 28m
Frontier
Deal found 3/8![Frontier logo]()
$101
This Frontier deal was found by Cheapflights users on 3/5. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/612:59 am
ONT
- MCI
1 stop10h 31m
Frontier
Deal found 3/5![Frontier logo]()
$101
This Trip.com deal was found by Cheapflights users on 3/6. Clicking the “Pick Dates” 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.
Thu 5/712:59 am
ONT
- MCI
1 stop10h 31m
Frontier
Deal found 3/6![Frontier logo]()
$104
This Trip.com deal was found by Cheapflights users on 3/10. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/116:20 am
ONT
- MCI
1 stop11h 38m
Frontier
Deal found 3/10![Frontier logo]()
$105
This Kiwi.com deal was found by Cheapflights users on 3/10. 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.
Sun 4/126:20 am
ONT
- STL
1 stop25h 28m
Frontier
Deal found 3/10![Frontier logo]()
$106
This CheapOair deal was found by Cheapflights users on 3/9. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/106:20 am
ONT
- STL
1 stop25h 28m
Frontier
Deal found 3/9![Frontier logo]()
$107
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 March 11, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $190 (Frontier) |
One-way from | $72 (Trip.com) |
Popular in | March |
Cheapest in | October |
Average price | $468 |
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 March 11, 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
OntarioColumbia
ONT - COU
ONTCOU
Ontario
Fri 4/24
7:35 pm-9:46 am
2 stops12h 11m
Columbia Regional
Sun 4/26
7:43 pm-11:46 pm
1 stop6h 03m
$304
OntarioSpringfield
ONT - SGF
ONTSGF
Ontario
Wed 4/22
1:34 pm-9:01 pm
1 stop5h 27m
Springfield-Branson
Tue 4/28
3:10 pm-10:31 pm
1 stop9h 21m
$309
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Sat 4/11
1:20 pm-9:31 pm
1 stop6h 11m
Lambert-St Louis
Wed 4/15
6:45 pm-11:44 pm
1 stop6h 59m
$317
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Wed 4/29
7:00 am-4:17 pm
1 stop7h 17m
Kansas City
Sat 5/2
5:11 pm-11:48 pm
1 stop8h 37m
$317
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Tue 3/31
1:34 pm-8:34 pm
1 stop5h 00m
Kansas City
Sat 4/4
7:00 am-12:20 pm
1 stop7h 20m
$317
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Tue 5/19
1:35 pm-11:35 pm
1 stop8h 00m
Kansas City
Thu 5/28
7:40 pm-11:34 pm
1 stop5h 54m
$336
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Wed 4/1
5:09 pm-12:46 am
1 stop5h 37m
Kansas City
Tue 4/7
8:11 pm-11:51 pm
1 stop5h 40m
$368
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Sat 4/18
6:00 am-11:59 pm
1 stop15h 59m
Kansas City
Tue 4/21
6:15 am-11:59 pm
1 stop19h 44m
$370
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Fri 5/15
7:00 am-4:37 pm
1 stop7h 37m
Lambert-St Louis
Tue 5/19
5:33 pm-11:56 pm
1 stop8h 23m
$387
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Tue 5/12
6:00 am-1:32 pm
1 stop5h 32m
Lambert-St Louis
Fri 5/15
7:59 pm-11:34 pm
1 stop5h 35m
$387
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-COU
ONT-SGF
ONT-STL
ONT-MCI
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-COU
ONT-SGF
ONT-STL
ONT-MCI
What is the cheapest month to book a flight from Ontario to Missouri?
Currently, June is the cheapest month in which you can book a flight from Ontario to Missouri (average of $60). Flying from Ontario to Missouri in February is currently the most expensive (average of $158). 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.
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 March 11, 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
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Boarding
8.1
Food
7.0
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Boarding
8.1
Food
7.0
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Boarding
8.1
Food
7.0
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Boarding
8.1
Food
7.0
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Boarding
8.1
Food
7.0
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
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
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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 March 11, 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 March 11, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$98 | Average$371 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$115 | Average$221 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$236 | Average$459 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$247 | Average$425 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$268 | Average$452 | FlexibilityNo cancel fee | On-time71% |