$80+ 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 4/24. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — STL
Mar 24 — Mar 311
1 adult, Economy
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Find cheap flights from Ontario to Missouri 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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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Ontario to Missouri
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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 February 22, 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 February 22, 2026.
This Frontier deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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
Fri 4/178:06 pm
STL
- ONT
1 stop5h 49m
Frontier
Deal found 2/19![Frontier logo]()
$190
This Frontier deal was found by Cheapflights users on 2/20. Clicking the “Pick Dates” 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 2/20![Frontier logo]()
$190
This Booking.com deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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
Thu 4/238:06 pm
STL
- ONT
1 stop5h 49m
Frontier
Deal found 2/19![Frontier logo]()
$191
This Booking.com deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 3/102:23 pm
ONT
- STL
1 stop18h 56m
Frontier
Tue 3/178:06 pm
STL
- ONT
1 stop19h 22m
Frontier
Deal found 2/18![Frontier logo]()
$192
This Kiwi.com deal was found by Cheapflights users on 2/20. Clicking the “Pick Dates” 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 4/2712:59 am
ONT
- STL
2 stops27h 51m
Frontier
Sat 5/28:17 pm
STL
- ONT
1 stop13h 09m
Frontier
Deal found 2/20![Frontier logo]()
$193
This Booking.com deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 3/242:23 pm
ONT
- STL
1 stop18h 56m
Frontier
Wed 3/258:12 pm
STL
- ONT
1 stop5h 47m
Frontier
Deal found 2/19![Frontier logo]()
$197
This CheapOair deal was found by Cheapflights users on 2/20. Clicking the “Pick Dates” 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 4/175:33 pm
ONT
- STL
1 stop23h 59m
Frontier
Sun 4/199:55 pm
STL
- ONT
1 stop14h 19m
Frontier
Deal found 2/20![Frontier logo]()
$201
This CheapOair deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 4/175:33 pm
ONT
- MCI
1 stop18h 33m
Frontier
Fri 5/12:15 pm
MCI
- ONT
1 stop11h 40m
Frontier
Deal found 2/18![Frontier logo]()
$201
This Jetabroad deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Jetabroad is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/2612:59 am
ONT
- STL
1 stop16h 33m
Frontier
Sat 5/28:17 pm
STL
- ONT
1 stop13h 09m
Frontier
Deal found 2/22![Frontier logo]()
$210
This Frontier deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” 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 4/276:15 am
ONT
- STL
1 stop6h 21m
Frontier
Fri 5/18:06 pm
STL
- ONT
1 stop5h 49m
Frontier
Deal found 2/22![Frontier logo]()
$213
This Kiwi.com deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” 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 4/1511:44 am
ONT
- STL
2 stops29h 37m
Frontier
Sun 4/199:55 pm
STL
- ONT
1 stop14h 19m
Frontier
Deal found 2/22![Frontier logo]()
$216
This Frontier deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” 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.
Sun 4/511:00 am
ONT
- STL
1 stop8h 17m
Frontier
Fri 4/108:16 pm
STL
- ONT
1 stop5h 40m
Frontier
Deal found 2/22![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 February 22, 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 February 22, 2026.
This Booking.com deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 3/102:23 pm
ONT
- STL
1 stop18h 56m
Frontier
Tue 3/178:06 pm
STL
- ONT
1 stop19h 22m
Frontier
Deal found 2/18![Frontier logo]()
$192
This Expedia deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 4/216:00 am
ONT
- STL
1 stop15h 59m
Multiple Airlines
Sat 4/258:17 pm
STL
- ONT
1 stop5h 38m
Multiple Airlines
Deal found 2/18![Multiple Airlines logo]()
$257
This Alaska Airlines deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 5/97:00 am
ONT
- MCI
1 stop7h 17m
Alaska Airlines
Tue 5/127:00 am
MCI
- ONT
1 stop9h 32m
Alaska Airlines
Deal found 2/18![Alaska Airlines logo]()
$293
This Delta deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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
Sat 4/116:40 am
MCI
- ONT
1 stop7h 43m
Delta
Deal found 2/18![Delta logo]()
$293
This United Airlines deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 4/211:34 pm
ONT
- STL
1 stop5h 20m
United Airlines
Sat 4/252:40 pm
STL
- ONT
1 stop7h 56m
United Airlines
Deal found 2/19![United Airlines logo]()
$303
This American Airlines deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/611:58 pm
ONT
- SGF
1 stop7h 01m
American Airlines
Tue 3/106:00 am
SGF
- ONT
1 stop6h 06m
American Airlines
Deal found 2/18![American Airlines logo]()
$339
This Frontier deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 5/112:59 am
ONT
- MCI
1 stop11h 07m
Frontier
Sat 5/92:51 pm
MCI
- ONT
1 stop11h 04m
Frontier
Deal found 2/18![Frontier logo]()
$211
This Trip.com deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 5/912:59 am
ONT
- STL
1 stop16h 13m
Frontier
Thu 5/148:12 pm
STL
- ONT
1 stop5h 43m
Frontier
Deal found 2/19![Frontier logo]()
$222
This Expedia deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 4/176:15 am
ONT
- STL
1 stop5h 57m
Multiple Airlines
Tue 4/217:00 am
STL
- ONT
1 stop28h 45m
Multiple Airlines
Deal found 2/18![Multiple Airlines logo]()
$258
This Orbitz deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/114:02 pm
ONT
- MCI
1 stop19h 53m
Alaska Airlines
Tue 3/175:16 pm
MCI
- ONT
1 stop8h 36m
Alaska Airlines
Deal found 2/18![Alaska Airlines logo]()
$293
This Expedia deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 4/76:25 pm
ONT
- STL
2 stops27h 34m
Multiple Airlines
Fri 4/108:16 pm
STL
- ONT
1 stop5h 40m
Multiple Airlines
Deal found 2/19![Multiple Airlines logo]()
$268
This Delta deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/285:05 pm
ONT
- STL
1 stop5h 20m
Delta
Sat 5/26:00 am
STL
- ONT
1 stop7h 36m
Delta
Deal found 2/22![Delta logo]()
$303
This CheapOair deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 4/245:33 pm
ONT
- MCI
1 stop18h 33m
Frontier
Mon 4/272:15 pm
MCI
- ONT
1 stop11h 40m
Frontier
Deal found 2/18![Frontier logo]()
$251
This United Airlines deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 3/611:59 pm
ONT
- COU
1 stop8h 34m
United Airlines
Tue 3/102:41 pm
COU
- ONT
1 stop9h 37m
United Airlines
Deal found 2/19![United Airlines logo]()
$328
This Alaska Airlines deal was found by Cheapflights users on 2/21. Clicking the “Pick Dates” 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 4/216:00 am
ONT
- MCI
1 stop15h 59m
Alaska Airlines
Mon 4/277:00 am
MCI
- ONT
1 stop18h 59m
Alaska Airlines
Deal found 2/21![Alaska Airlines logo]()
$303
This Kiwi.com deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 4/217:44 pm
ONT
- STL
2 stops25h 35m
Frontier
Sat 4/258:17 pm
STL
- ONT
1 stop13h 09m
Frontier
Deal found 2/19![Frontier logo]()
$263
This American Airlines deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/1211:58 pm
ONT
- SGF
1 stop8h 11m
American Airlines
Sun 3/227:46 pm
SGF
- ONT
1 stop6h 13m
American Airlines
Deal found 2/18![American Airlines logo]()
$379
This Booking.com deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/36:20 am
ONT
- STL
1 stop25h 28m
Frontier
Wed 4/88:16 pm
STL
- ONT
1 stop5h 40m
Frontier
Deal found 2/18![Frontier logo]()
$269
This United Airlines deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 4/226:49 pm
ONT
- COU
2 stops14h 06m
United Airlines
Wed 4/293:23 pm
COU
- ONT
1 stop9h 03m
United Airlines
Deal found 2/19![United Airlines logo]()
$364
This Frontier deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 4/26:20 am
ONT
- MCI
1 stop11h 41m
Frontier
Sun 4/128:28 pm
MCI
- ONT
1 stop5h 28m
Frontier
Deal found 2/18![Frontier logo]()
$270
This United Airlines deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 4/226:05 am
ONT
- SGF
1 stop8h 22m
United Airlines
Wed 4/292:52 pm
SGF
- ONT
1 stop8h 58m
United Airlines
Deal found 2/19![United Airlines logo]()
$369
This Frontier deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 4/46:20 am
ONT
- MCI
1 stop11h 38m
Frontier
Sun 4/128:28 pm
MCI
- ONT
1 stop5h 28m
Frontier
Deal found 2/18![Frontier logo]()
$270
This United Airlines deal was found by Cheapflights users on 2/20. Clicking the “Pick Dates” 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 3/1111:59 pm
ONT
- SGF
1 stop8h 47m
United Airlines
Tue 3/243:10 pm
SGF
- ONT
1 stop9h 08m
United Airlines
Deal found 2/20![United Airlines logo]()
$394
This CheapOair deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 3/196:15 am
ONT
- STL
1 stop25h 34m
Frontier
Wed 3/2512:14 pm
STL
- ONT
1 stop10h 49m
Frontier
Deal found 2/19![Frontier logo]()
$271
This American Airlines deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 4/2410:59 am
ONT
- COU
1 stop6h 14m
American Airlines
Sun 4/267:43 pm
COU
- ONT
1 stop6h 03m
American Airlines
Deal found 2/19![American Airlines logo]()
$524
This United Airlines deal was found by Cheapflights users on 2/20. Clicking the “Pick Dates” 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 3/105:15 am
ONT
- SGF
1 stop5h 31m
United Airlines
Tue 3/243:10 pm
SGF
- ONT
1 stop9h 08m
United Airlines
Deal found 2/20![United Airlines logo]()
$394
This Kiwi.com deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 4/36:20 am
ONT
- MCI
1 stop11h 38m
Frontier
Mon 4/68:43 pm
MCI
- ONT
1 stop29h 13m
Frontier
Deal found 2/18![Frontier logo]()
$272
This Kiwi.com deal was found by Cheapflights users on 2/21. Clicking the “Pick Dates” 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 3/112:23 pm
ONT
- STL
1 stop26h 48m
Frontier
Wed 3/188:12 pm
STL
- ONT
1 stop29h 47m
Frontier
Deal found 2/21![Frontier logo]()
$290
This American Airlines deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 4/412:26 pm
ONT
- SGF
2 stops9h 29m
American Airlines
Sat 4/1110:54 am
SGF
- ONT
2 stops7h 28m
American Airlines
Deal found 2/19![American Airlines logo]()
$579
This United Airlines deal was found by Cheapflights users on 2/22. Clicking the “Pick Dates” 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 5/291:18 pm
ONT
- COU
1 stop5h 21m
United Airlines
Fri 6/193:05 pm
COU
- ONT
1 stop9h 41m
United Airlines
Deal found 2/22![United Airlines logo]()
$443
Last-minute flights from Ontario to MissouriDiscover last-minute flight deals from Ontario to Missouri. Data last updated February 22, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Missouri. Data last updated February 22, 2026 and is based on user searches.
This Trip.com deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 2/267:22 pm
ONT
- STL
1 stop24h 04m
Frontier
Mon 3/210:11 pm
STL
- ONT
1 stop17h 00m
Frontier
Deal found 2/18![Frontier logo]()
$240
This CheapOair deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 2/267:22 pm
ONT
- STL
1 stop24h 04m
Frontier
Sun 3/110:11 pm
STL
- ONT
1 stop21h 37m
Frontier
Deal found 2/18![Frontier logo]()
$243
This Expedia deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 2/279:43 pm
ONT
- STL
1 stop18h 03m
Frontier
Mon 3/210:11 pm
STL
- ONT
1 stop17h 00m
Frontier
Deal found 2/18![Frontier logo]()
$232
This CheapOair deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 3/47:17 pm
ONT
- STL
1 stop24h 09m
Frontier
Sun 3/86:19 pm
STL
- ONT
1 stop23h 18m
Frontier
Deal found 2/18![Frontier logo]()
$241
This Booking.com deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 3/102:23 pm
ONT
- STL
1 stop18h 56m
Frontier
Tue 3/178:06 pm
STL
- ONT
1 stop19h 22m
Frontier
Deal found 2/18![Frontier logo]()
$192
This Kiwi.com deal was found by Cheapflights users on 2/21. Clicking the “Pick Dates” 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 3/112:23 pm
ONT
- STL
2 stops30h 56m
Frontier
Wed 3/188:12 pm
STL
- ONT
1 stop29h 47m
Frontier
Deal found 2/21![Frontier logo]()
$237
This Mytrip deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 3/176:15 am
ONT
- STL
1 stop25h 34m
Frontier
Sat 3/218:12 pm
STL
- ONT
1 stop5h 47m
Frontier
Deal found 2/18![Frontier logo]()
$226
This Booking.com deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 3/242:23 pm
ONT
- STL
1 stop18h 56m
Frontier
Wed 3/258:12 pm
STL
- ONT
1 stop5h 47m
Frontier
Deal found 2/19![Frontier logo]()
$197
This Booking.com deal was found by Cheapflights users on 2/20. Clicking the “Pick Dates” 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 3/242:23 pm
ONT
- STL
1 stop18h 56m
Frontier
Sat 3/288:12 pm
STL
- ONT
1 stop5h 47m
Frontier
Deal found 2/20![Frontier logo]()
$227
This Frontier deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 3/279:49 pm
ONT
- STL
1 stop11h 30m
Frontier
Fri 4/108:16 pm
STL
- ONT
1 stop5h 40m
Frontier
Deal found 2/18![Frontier logo]()
$220
This Frontier deal was found by Cheapflights users on 2/21. Clicking the “Pick Dates” 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 3/276:15 am
ONT
- MCI
1 stop11h 40m
Frontier
Tue 4/78:43 pm
MCI
- ONT
1 stop5h 13m
Frontier
Deal found 2/21![Frontier logo]()
$240
This Kiwi.com deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/312:23 pm
ONT
- MCI
1 stop24h 46m
Multiple Airlines
Tue 4/78:43 pm
MCI
- ONT
1 stop29h 13m
Multiple Airlines
Deal found 2/19![Multiple Airlines logo]()
$229
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 February 22, 2026.
Search for one-way flight options from Ontario to Missouri. Find affordable one-way fares based on user searches. Data last updated February 22, 2026.
This Trip.com deal was found by Cheapflights users on 2/21. Clicking the “Pick Dates” 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 4/2412:59 am
ONT
- MCI
1 stop11h 07m
Frontier
Deal found 2/21![Frontier logo]()
$80
This Kiwi.com deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/246:15 am
ONT
- STL
1 stop25h 34m
Frontier
Deal found 2/19![Frontier logo]()
$94
This Booking.com deal was found by Cheapflights users on 2/20. Clicking the “Pick Dates” 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 4/206:15 am
ONT
- STL
1 stop6h 21m
Frontier
Deal found 2/20![Frontier logo]()
$95
This Trip.com deal was found by Cheapflights users on 2/21. Clicking the “Pick Dates” 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.
Sun 5/312:59 am
ONT
- MCI
1 stop10h 31m
Frontier
Deal found 2/21![Frontier logo]()
$96
This Super.com deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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 4/157:44 pm
ONT
- STL
1 stop23h 16m
Frontier
Deal found 2/18![Frontier logo]()
$99
This Trip.com deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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 3/126:15 am
ONT
- STL
1 stop25h 34m
Frontier
Deal found 2/19![Frontier logo]()
$101
This Frontier deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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
Deal found 2/19![Frontier logo]()
$101
This CheapOair deal was found by Cheapflights users on 2/20. Clicking the “Pick Dates” 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 5/712:59 am
ONT
- STL
1 stop16h 13m
Frontier
Deal found 2/20![Frontier logo]()
$107
This CheapOair deal was found by Cheapflights users on 2/19. Clicking the “Pick Dates” 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.
Sun 5/35:12 pm
ONT
- MCI
1 stop18h 18m
Frontier
Deal found 2/19![Frontier logo]()
$107
This Trip.com deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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.
Sun 3/151:55 pm
ONT
- STL
1 stop19h 24m
Frontier
Deal found 2/18![Frontier logo]()
$113
This Mytrip deal was found by Cheapflights users on 2/18. Clicking the “Pick Dates” 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.
Sat 2/286:00 am
ONT
- STL
1 stop5h 56m
Frontier
Deal found 2/18![Frontier logo]()
$116
This Priceline deal was found by Cheapflights users on 2/20. Clicking the “Pick Dates” 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.
Wed 3/48:40 am
ONT
- MCI
1 stop5h 04m
Frontier
Deal found 2/20![Frontier logo]()
$116
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 February 22, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $190 (Frontier) |
One-way from | $80 (Trip.com) |
Popular in | February |
Cheapest in | October |
Average price | $437 |
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 February 22, 2026.
Use the filters below to find and compare flights from Ontario to Missouri that are best for you.
Fly from
Ontario
Fly to
Missouri
Route
Depart
Return
Price
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Tue 3/10
2:23 pm-11:19 am
1 stop18h 56m
Lambert-St Louis
Tue 3/17
8:06 pm-1:28 pm
1 stop19h 22m
$192
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Fri 5/1
12:59 am-2:06 pm
1 stop11h 07m
Kansas City
Sat 5/9
2:51 pm-11:55 pm
1 stop11h 04m
$211
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Sat 5/9
12:59 am-7:12 pm
1 stop16h 13m
Lambert-St Louis
Thu 5/14
8:12 pm-11:55 pm
1 stop5h 43m
$222
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Fri 4/24
5:33 pm-2:06 pm
1 stop18h 33m
Kansas City
Mon 4/27
2:15 pm-11:55 pm
1 stop11h 40m
$251
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Tue 4/21
6:00 am-11:59 pm
1 stop15h 59m
Lambert-St Louis
Sat 4/25
8:17 pm-11:55 pm
1 stop5h 38m
$257
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Fri 4/17
6:15 am-2:12 pm
1 stop5h 57m
Lambert-St Louis
Tue 4/21
7:00 am-9:45 am
1 stop28h 45m
$258
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Tue 4/21
7:44 pm-11:19 pm
2 stops25h 35m
Lambert-St Louis
Sat 4/25
8:17 pm-7:26 am
1 stop13h 09m
$263
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Tue 4/7
6:25 pm-11:59 pm
2 stops27h 34m
Lambert-St Louis
Fri 4/10
8:16 pm-11:56 pm
1 stop5h 40m
$268
OntarioSt. Louis
ONT - STL
ONTSTL
Ontario
Fri 4/3
6:20 am-9:48 am
1 stop25h 28m
Lambert-St Louis
Wed 4/8
8:16 pm-11:56 pm
1 stop5h 40m
$269
OntarioKansas City
ONT - MCI
ONTMCI
Ontario
Thu 4/2
6:20 am-8:01 pm
1 stop11h 41m
Kansas City
Sun 4/12
8:28 pm-11:56 pm
1 stop5h 28m
$270
Showing 1-10 of 60 results
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
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 November is currently the most expensive (average of $149). 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 February 22, 2026.
See what other customers who have flown with Southwest, Delta, and United 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.
Food
7.0
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Food
7.0
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Food
7.0
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Food
7.0
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Food
7.0
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Food
7.0
Crew
8.6
Entertainment
7.5
Overall
8.0
Comfort
8.0
Boarding
8.1
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 February 22, 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 February 22, 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$463 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$247 | Average$421 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$268 | Average$446 | FlexibilityNo cancel fee | On-time71% |