$101+ Cheap flights from Missouri to Ontario (ONT)
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 8/18. Fares are subject to change and may not be available on all flights or dates of travel.
STL — ONT
Jun 15 — Jun 221
Round-trip
1 adult, Economy
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Find cheap flights from Missouri to Ontario with Cheapflights
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Cheapest flights from Missouri to OntarioExplore the most affordable flight options available from Missouri to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 16, 2026.
Explore the most affordable flight options available from Missouri to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 16, 2026.
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.
Wed 6/36:51 pm
STL
- ONT
1 stop22h 18m
Frontier
Wed 6/173:34 pm
ONT
- STL
1 stop20h 32m
Frontier
Deal found 5/12![Frontier logo]()
$210
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.
Sat 6/272:56 pm
STL
- ONT
1 stop6h 55m
Frontier
Tue 6/301:33 pm
ONT
- STL
1 stop27h 18m
Frontier
Deal found 5/11![Frontier logo]()
$224
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 6/32:34 pm
MCI
- ONT
1 stop11h 15m
Frontier
Wed 6/106:00 am
ONT
- MCI
1 stop5h 00m
Frontier
Deal found 5/12![Frontier logo]()
$229
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.
Wed 6/36:51 pm
STL
- ONT
1 stop22h 18m
Frontier
Sat 6/66:00 am
ONT
- STL
1 stop11h 23m
Frontier
Deal found 5/12![Frontier logo]()
$230
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/41:45 pm
MCI
- ONT
1 stop12h 05m
Frontier
Tue 8/116:00 am
ONT
- MCI
1 stop4h 55m
Frontier
Deal found 5/13![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.
Sat 6/68:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Mon 6/86:00 am
ONT
- STL
1 stop11h 23m
Frontier
Deal found 5/12![Frontier logo]()
$238
This Frontier deal was found by Cheapflights users on 5/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/242:17 pm
MCI
- ONT
1 stop11h 38m
Frontier
Mon 9/286:00 am
ONT
- MCI
1 stop5h 22m
Frontier
Deal found 5/12![Frontier logo]()
$238
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 5/308:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Tue 6/26:00 am
ONT
- STL
1 stop11h 23m
Frontier
Deal found 5/11![Frontier logo]()
$240
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/191:45 pm
MCI
- ONT
1 stop12h 04m
Frontier
Tue 7/76:00 am
ONT
- MCI
1 stop4h 55m
Frontier
Deal found 5/13![Frontier logo]()
$240
This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/11:45 pm
MCI
- ONT
1 stop22h 20m
Frontier
Tue 7/76:00 am
ONT
- MCI
1 stop4h 55m
Frontier
Deal found 5/14![Frontier logo]()
$241
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/17:46 pm
STL
- ONT
1 stop26h 05m
Frontier
Sun 7/511:43 am
ONT
- STL
1 stop24h 24m
Frontier
Deal found 5/11![Frontier logo]()
$242
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/231:45 pm
MCI
- ONT
1 stop12h 05m
Frontier
Wed 7/291:28 pm
ONT
- MCI
1 stop21h 27m
Frontier
Deal found 5/11![Frontier logo]()
$242
Best flights from Missouri to OntarioDiscover carefully curated flight deals from Missouri to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 16, 2026.
Discover carefully curated flight deals from Missouri to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 16, 2026.
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 7/252:52 pm
STL
- ONT
1 stop7h 01m
Frontier
Tue 7/286:00 am
ONT
- STL
1 stop11h 23m
Frontier
Deal found 5/11![Frontier logo]()
$264
This Southwest deal was found by Cheapflights users on 5/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/85:20 pm
MCI
- ONT
1 stop5h 45m
Southwest
Mon 6/154:40 pm
ONT
- MCI
1 stop5h 15m
Southwest
Deal found 5/11![Southwest logo]()
$437
This United Airlines deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” 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 5/303:25 pm
COU
- ONT
1 stop9h 26m
United Airlines
Tue 6/161:18 pm
ONT
- COU
1 stop5h 21m
United Airlines
Deal found 5/15![United Airlines logo]()
$443
This American Airlines deal was found by Cheapflights users on 5/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/195:17 pm
COU
- ONT
1 stop7h 41m
American Airlines
Sun 8/237:06 am
ONT
- COU
1 stop7h 40m
American Airlines
Deal found 5/12![American Airlines logo]()
$474
This Alaska Airlines deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” 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 8/2211:27 am
SGF
- ONT
2 stops13h 57m
Alaska Airlines
Tue 8/257:10 am
ONT
- SGF
2 stops10h 08m
Alaska Airlines
Deal found 5/15![Alaska Airlines logo]()
$529
This Delta deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/266:00 am
SGF
- ONT
1 stop7h 04m
Delta
Mon 9/2810:59 pm
ONT
- SGF
1 stop10h 02m
Delta
Deal found 5/15![Delta logo]()
$529
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.
Fri 7/178:08 pm
STL
- ONT
1 stop5h 42m
Frontier
Sun 7/196:00 am
ONT
- STL
1 stop11h 23m
Frontier
Deal found 5/11![Frontier logo]()
$270
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 7/91:45 pm
MCI
- ONT
1 stop12h 05m
Frontier
Wed 7/226:00 am
ONT
- MCI
1 stop4h 55m
Frontier
Deal found 5/11![Frontier logo]()
$290
This Frontier deal was found by Cheapflights users on 5/16. Clicking the “Pick Dates” 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 6/62:34 pm
MCI
- ONT
1 stop11h 15m
Frontier
Sat 6/136:00 am
ONT
- MCI
1 stop5h 00m
Frontier
Deal found 5/16![Frontier logo]()
$310
This Kiwi.com deal was found by Cheapflights users on 5/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/106:16 pm
MCI
- ONT
2 stops22h 51m
Frontier
Tue 7/146:00 am
ONT
- MCI
1 stop28h 55m
Frontier
Deal found 5/11![Frontier logo]()
$313
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.
Fri 7/106:55 am
MCI
- ONT
2 stops6h 25m
Southwest
Tue 7/141:30 pm
ONT
- MCI
2 stops6h 30m
Southwest
Deal found 5/11![Southwest logo]()
$439
This United Airlines deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” 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 7/295:10 am
STL
- ONT
2 stops9h 02m
United Airlines
Wed 8/55:00 am
ONT
- STL
1 stop5h 42m
United Airlines
Deal found 5/15![United Airlines logo]()
$456
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/127:39 pm
COU
- ONT
1 stop6h 20m
American Airlines
Sun 6/1412:41 pm
ONT
- COU
1 stop7h 39m
American Airlines
Deal found 5/14![American Airlines logo]()
$477
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 6/108:35 am
STL
- ONT
2 stops8h 20m
Southwest
Tue 6/236:10 am
ONT
- STL
2 stops8h 10m
Southwest
Deal found 5/13![Southwest logo]()
$461
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/161:45 pm
MCI
- ONT
1 stop22h 20m
Frontier
Mon 7/66:00 am
ONT
- MCI
1 stop4h 55m
Frontier
Deal found 5/11![Frontier logo]()
$347
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 8/259:00 am
COU
- ONT
1 stop5h 50m
United Airlines
Sat 8/291:18 pm
ONT
- COU
1 stop5h 41m
United Airlines
Deal found 5/11![United Airlines logo]()
$474
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.
Tue 5/267:41 pm
STL
- ONT
1 stop17h 31m
Alaska Airlines
Mon 6/18:11 pm
ONT
- STL
1 stop17h 05m
Alaska Airlines
Deal found 5/11![Alaska Airlines logo]()
$531
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 7/95:35 am
STL
- ONT
2 stops7h 45m
Southwest
Tue 7/146:10 am
ONT
- STL
2 stops8h 10m
Southwest
Deal found 5/14![Southwest logo]()
$468
This United Airlines deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” 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 8/1110:00 am
MCI
- ONT
2 stops12h 01m
United Airlines
Wed 8/127:00 am
ONT
- MCI
1 stop7h 12m
United Airlines
Deal found 5/15![United Airlines logo]()
$486
This Frontier deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” 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 5/242:34 pm
MCI
- ONT
1 stop11h 15m
Frontier
Mon 5/256:00 am
ONT
- MCI
1 stop5h 49m
Frontier
Deal found 5/15![Frontier logo]()
$370
This Southwest deal was found by Cheapflights users on 5/16. Clicking the “Pick Dates” 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 6/255:35 am
STL
- ONT
2 stops7h 45m
Southwest
Fri 6/264:20 pm
ONT
- STL
1 stop6h 15m
Southwest
Deal found 5/16![Southwest logo]()
$482
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.
Wed 9/210:16 am
COU
- ONT
2 stops11h 45m
United Airlines
Sat 9/51:18 pm
ONT
- COU
1 stop5h 41m
United Airlines
Deal found 5/14![United Airlines logo]()
$495
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 6/52:55 pm
STL
- ONT
2 stops8h 10m
Southwest
Tue 6/96:10 am
ONT
- STL
2 stops8h 10m
Southwest
Deal found 5/14![Southwest logo]()
$484
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.
Tue 9/15:30 am
SGF
- ONT
1 stop9h 20m
United Airlines
Wed 9/306:00 am
ONT
- SGF
1 stop8h 14m
United Airlines
Deal found 5/13![United Airlines logo]()
$507
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 6/125:55 am
MCI
- ONT
2 stops7h 25m
Southwest
Fri 6/1912:45 pm
ONT
- MCI
2 stops8h 35m
Southwest
Deal found 5/14![Southwest logo]()
$497
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.
Fri 8/211:53 pm
JLN
- ONT
2 stops8h 08m
United Airlines
Tue 8/251:56 pm
ONT
- JLN
2 stops31h 48m
United Airlines
Deal found 5/12![United Airlines logo]()
$511
This Alaska 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/812:55 pm
SGF
- ONT
2 stops12h 56m
Alaska Airlines
Wed 7/155:54 pm
ONT
- SGF
2 stops12h 57m
Alaska Airlines
Deal found 5/14![Alaska Airlines logo]()
$768
This Southwest deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” 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 6/108:35 am
STL
- ONT
2 stops8h 20m
Southwest
Sun 6/145:15 am
ONT
- STL
2 stops7h 30m
Southwest
Deal found 5/15![Southwest logo]()
$502
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.
Tue 6/2312:46 pm
SGF
- ONT
2 stops12h 25m
Alaska Airlines
Tue 6/305:26 pm
ONT
- SGF
2 stops13h 33m
Alaska Airlines
Deal found 5/11![Alaska Airlines logo]()
$819
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 6/125:55 am
MCI
- ONT
2 stops7h 25m
Southwest
Sun 6/1411:55 pm
ONT
- MCI
1 stop7h 35m
Southwest
Deal found 5/14![Southwest logo]()
$512
Last-minute flights from Missouri to OntarioDiscover last-minute flight deals from Missouri to Ontario. Data last updated May 16, 2026 and is based on user searches.
Discover last-minute flight deals from Missouri to Ontario. Data last updated May 16, 2026 and is based on user searches.
This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/298:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Tue 7/73:40 pm
ONT
- STL
1 stop24h 25m
Frontier
Deal found 5/13![Frontier logo]()
$251
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 5/308:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Tue 6/26:00 am
ONT
- STL
1 stop11h 23m
Frontier
Deal found 5/11![Frontier logo]()
$240
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.
Wed 6/36:51 pm
STL
- ONT
1 stop22h 18m
Frontier
Wed 6/173:34 pm
ONT
- STL
1 stop20h 32m
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 6/32:34 pm
MCI
- ONT
1 stop11h 15m
Frontier
Wed 6/106:00 am
ONT
- MCI
1 stop5h 00m
Frontier
Deal found 5/12![Frontier logo]()
$229
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.
Wed 6/36:51 pm
STL
- ONT
1 stop22h 18m
Frontier
Sat 6/66:00 am
ONT
- STL
1 stop11h 23m
Frontier
Deal found 5/12![Frontier logo]()
$230
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.
Thu 6/42:34 pm
MCI
- ONT
1 stop11h 15m
Frontier
Mon 6/86:00 am
ONT
- MCI
1 stop5h 49m
Frontier
Deal found 5/12![Frontier logo]()
$250
This Frontier deal was found by Cheapflights users on 5/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/42:34 pm
MCI
- ONT
1 stop11h 15m
Frontier
Wed 6/106:00 am
ONT
- MCI
1 stop5h 00m
Frontier
Deal found 5/12![Frontier logo]()
$251
This Frontier deal was found by Cheapflights users on 5/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/68:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Mon 6/86:00 am
ONT
- STL
1 stop11h 23m
Frontier
Deal found 5/12![Frontier logo]()
$238
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 6/98:08 pm
STL
- ONT
1 stop15h 57m
Frontier
Tue 6/161:33 pm
ONT
- STL
1 stop27h 18m
Frontier
Deal found 5/12![Frontier logo]()
$246
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/161:45 pm
MCI
- ONT
1 stop22h 20m
Frontier
Sat 7/43:34 pm
ONT
- MCI
1 stop19h 21m
Frontier
Deal found 5/13![Frontier logo]()
$252
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/191:45 pm
MCI
- ONT
1 stop12h 04m
Frontier
Tue 7/76:00 am
ONT
- MCI
1 stop4h 55m
Frontier
Deal found 5/13![Frontier logo]()
$240
This Orbitz 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/301:45 pm
MCI
- ONT
1 stop22h 20m
Frontier
Sun 7/123:40 pm
ONT
- MCI
1 stop19h 15m
Frontier
Deal found 5/13![Frontier logo]()
$246
One-way flights from Missouri to OntarioSearch for one-way flight options from Missouri to Ontario. Find affordable one-way fares based on user searches. Data last updated May 16, 2026.
Search for one-way flight options from Missouri to Ontario. Find affordable one-way fares based on user searches. Data last updated May 16, 2026.
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 8/188:08 pm
STL
- ONT
1 stop5h 41m
Frontier
Deal found 5/11![Frontier logo]()
$101
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 6/107:03 pm
STL
- ONT
1 stop22h 05m
Frontier
Deal found 5/12![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.
Tue 7/141:45 pm
MCI
- ONT
1 stop22h 18m
Frontier
Deal found 5/12![Frontier logo]()
$106
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 8/52:51 pm
SGF
- ONT
1 stop7h 02m
Multiple Airlines
Deal found 5/12![Multiple Airlines 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 7/17:46 pm
STL
- ONT
1 stop21h 22m
Frontier
Deal found 5/12![Frontier logo]()
$109
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 6/91:45 pm
MCI
- ONT
1 stop22h 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.
Wed 6/241:45 pm
MCI
- ONT
1 stop22h 20m
Frontier
Deal found 5/13![Frontier logo]()
$116
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.
Sat 7/111:45 pm
MCI
- ONT
1 stop22h 18m
Frontier
Deal found 5/11![Frontier logo]()
$119
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 6/49:06 pm
STL
- ONT
1 stop20h 03m
Frontier
Deal found 5/12![Frontier logo]()
$120
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.
Fri 8/141:50 pm
MCI
- ONT
1 stop8h 03m
Frontier
Deal found 5/13![Frontier logo]()
$120
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 8/41:45 pm
MCI
- ONT
1 stop12h 05m
Frontier
Deal found 5/12![Frontier logo]()
$121
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.
Sat 6/202:56 pm
STL
- ONT
1 stop6h 55m
Frontier
Deal found 5/12![Frontier logo]()
$123
Find flight deals from Missouri to Ontario
Keep the following information in mind while searching for Missouri to Ontario flight deals. Data was last updated May 16, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $210 (Frontier) |
One-way from | $101 (Super.com) |
Popular in | May |
Cheapest in | September |
Average price | $437 |
Cheapflights Fare Finder
Customize your flight search to find flights from Missouri to Ontario 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 16, 2026.
Use the filters below to find and compare flights from Missouri to Ontario that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisOntario
STL - ONT
STLONT
Lambert-St Louis
Sat 7/25
2:52 pm-7:53 pm
1 stop7h 01m
Ontario
Tue 7/28
6:00 am-7:23 pm
1 stop11h 23m
$264
St. LouisOntario
STL - ONT
STLONT
Lambert-St Louis
Fri 7/17
8:08 pm-11:50 pm
1 stop5h 42m
Ontario
Sun 7/19
6:00 am-7:23 pm
1 stop11h 23m
$270
Kansas CityOntario
MCI - ONT
MCIONT
Kansas City
Thu 7/9
1:45 pm-11:50 pm
1 stop12h 05m
Ontario
Wed 7/22
6:00 am-12:55 pm
1 stop4h 55m
$290
Kansas CityOntario
MCI - ONT
MCIONT
Kansas City
Sat 6/6
2:34 pm-11:49 pm
1 stop11h 15m
Ontario
Sat 6/13
6:00 am-1:00 pm
1 stop5h 00m
$310
Kansas CityOntario
MCI - ONT
MCIONT
Kansas City
Fri 7/10
6:16 pm-3:07 pm
2 stops22h 51m
Ontario
Tue 7/14
6:00 am-12:55 pm
1 stop28h 55m
$313
Kansas CityOntario
MCI - ONT
MCIONT
Kansas City
Tue 6/16
1:45 pm-10:05 am
1 stop22h 20m
Ontario
Mon 7/6
6:00 am-12:55 pm
1 stop4h 55m
$347
Kansas CityOntario
MCI - ONT
MCIONT
Kansas City
Sun 5/24
2:34 pm-11:49 pm
1 stop11h 15m
Ontario
Mon 5/25
6:00 am-1:49 pm
1 stop5h 49m
$370
Quickest round-trip
Kansas CityOntario
MCI - ONT
MCIONT
Kansas City
Mon 6/8
5:20 pm-9:05 pm
1 stop5h 45m
Ontario
Mon 6/15
4:40 pm-11:55 pm
1 stop5h 15m
$437
Kansas CityOntario
MCI - ONT
MCIONT
Kansas City
Fri 7/10
6:55 am-11:20 am
2 stops6h 25m
Ontario
Tue 7/14
1:30 pm-10:00 pm
2 stops6h 30m
$439
ColumbiaOntario
COU - ONT
COUONT
Columbia Regional
Sat 5/30
3:25 pm-10:51 pm
1 stop9h 26m
Ontario
Tue 6/16
1:18 pm-8:39 pm
1 stop5h 21m
$443
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Missouri to Ontario
Have a flexible travel schedule? Discover the best time to fly to Ontario from Missouri with our price prediction graph.
STL-ONT
SGF-ONT
MCI-ONT
COU-ONT
JLN-ONT
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Missouri to Ontario
USMO-ONT
STL-ONT
SGF-ONT
MCI-ONT
COU-ONT
What is the cheapest month to book a flight from Missouri to Ontario?
Currently, August is the cheapest month in which you can book a flight from Missouri to Ontario (average of $61). Flying from Missouri to Ontario in February is currently the most expensive (average of $284). 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 Missouri to Ontario?
Related info for your journey
Find useful and relevant information for your journey from Missouri to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
Alternative routes
Complete your trip
Flights by cabin class
Ontario flight routes
Other flight options
Popular flights
Top destinations
Alternative routes for Missouri to Ontario
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Ontario by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Missouri to Ontario by cabin class
Find flights from Missouri to Ontario, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Other flights to Ontario
Explore flights to Ontario departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on May 16, 2026.
Missouri and Ontario flights
Browse other Missouri and Ontario flight options. Last updated on May 16, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Missouri to Ontario flights
Consider these flights traveling from Missouri to Ontario.
Top 5 airlines flying from Missouri to Ontario
Discover the top 5 airlines that operate flights from Missouri to Ontario. 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 16, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$94 | Average$261 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$253 | Average$412 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$264 | Average$423 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$269 | Average$405 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$276 | Average$378 | FlexibilityNo cancel fee | On-timeN/A |