$183+ Cheap flights from Ontario to Missouri
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 6/10. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — STL
May 31 — Jun 71
Round-trip
1 adult, Economy
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Find cheap flights from Ontario to Missouri with Cheapflights
1. Tell us where you want to go
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Cheapest flights from Ontario to MissouriExplore the most affordable flight options available from Ontario to Missouri. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 1, 2026.
Explore the most affordable flight options available from Ontario to Missouri. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 1, 2026.
This Air Canada deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/232:40 pm
YOW
- STL
1 stop6h 45m
Air Canada
Sun 5/247:05 am
STL
- YOW
1 stop5h 00m
Air Canada
Deal found 4/28![Air Canada logo]()
$314
This United Airlines deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 5/235:50 pm
YOW
- STL
1 stop6h 45m
United Airlines
Wed 5/276:00 am
STL
- YOW
1 stop9h 38m
United Airlines
Deal found 4/26![United Airlines logo]()
$320
This United Airlines deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/210:44 am
YOW
- STL
1 stop11h 32m
United Airlines
Wed 6/36:00 am
STL
- YOW
1 stop9h 38m
United Airlines
Deal found 4/27![United Airlines logo]()
$321
This United Airlines deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 7/246:25 am
YOW
- STL
1 stop10h 21m
United Airlines
Sat 8/81:13 pm
STL
- YOW
1 stop7h 22m
United Airlines
Deal found 4/29![United Airlines logo]()
$328
This American Airlines deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 5/2711:39 am
YYZ
- STL
1 stop9h 51m
American Airlines
Wed 6/107:03 am
STL
- YYZ
1 stop9h 41m
American Airlines
Deal found 4/30![American Airlines logo]()
$344
This Air Canada deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/147:00 am
YOW
- STL
1 stop6h 06m
Air Canada
Sun 6/212:15 pm
STL
- YOW
1 stop9h 30m
Air Canada
Deal found 4/30![Air Canada logo]()
$353
This Kiwi.com deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/279:50 am
YYZ
- STL
1 stop15h 07m
Multiple Airlines
Wed 6/35:27 pm
STL
- YYZ
2 stops29h 13m
Multiple Airlines
Deal found 4/27![Multiple Airlines logo]()
$356
This United Airlines deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 8/126:00 am
YOW
- STL
2 stops10h 38m
United Airlines
Wed 8/195:00 am
STL
- YOW
2 stops8h 11m
United Airlines
Deal found 4/30![United Airlines logo]()
$381
This Kiwi.com deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 6/129:50 am
YYZ
- STL
1 stop15h 19m
Multiple Airlines
Fri 6/194:17 pm
STL
- YYZ
1 stop26h 48m
Multiple Airlines
Deal found 4/28![Multiple Airlines logo]()
$381
This Kiwi.com deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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.
Thu 6/49:50 am
YYZ
- STL
1 stop15h 07m
Multiple Airlines
Sun 6/77:20 pm
STL
- YYZ
2 stops25h 35m
Multiple Airlines
Deal found 4/29![Multiple Airlines logo]()
$386
This American Airlines deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/277:20 am
YYZ
- STL
1 stop7h 46m
American Airlines
Wed 6/39:24 am
STL
- YYZ
1 stop4h 35m
American Airlines
Deal found 4/27![American Airlines logo]()
$391
This Kiwi.com deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 5/299:50 am
YYZ
- STL
1 stop15h 07m
Multiple Airlines
Fri 6/511:24 am
STL
- YYZ
2 stops32h 31m
Multiple Airlines
Deal found 4/30![Multiple Airlines logo]()
$397
Best flights from Ontario to MissouriDiscover carefully curated flight deals from Ontario to Missouri that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 1, 2026.
Discover carefully curated flight deals from Ontario to Missouri that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 1, 2026.
This United Airlines deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/26:00 am
YOW
- STL
2 stops10h 46m
United Airlines
Wed 6/36:00 am
STL
- YOW
1 stop15h 05m
United Airlines
Deal found 4/28![United Airlines logo]()
$320
This Kiwi.com deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 5/299:50 am
YYZ
- STL
1 stop15h 07m
Multiple Airlines
Fri 6/511:24 am
STL
- YYZ
2 stops32h 31m
Multiple Airlines
Deal found 4/30![Multiple Airlines logo]()
$397
This Delta deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/46:10 am
YYZ
- STL
1 stop4h 19m
Delta
Mon 6/89:21 am
STL
- YYZ
1 stop6h 58m
Delta
Deal found 4/26![Delta logo]()
$426
This Air Canada deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/296:30 pm
YUL
- STL
Nonstop2h 55m
Air Canada
Mon 6/12:15 pm
STL
- YUL
1 stop5h 36m
Air Canada
Deal found 4/26![Air Canada logo]()
$430
This FlightHub deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/217:22 pm
YYZ
- MCI
1 stop4h 54m
WestJet
Sun 5/245:39 am
MCI
- YYZ
1 stop5h 40m
WestJet
Deal found 4/26![WestJet logo]()
$525
This American Airlines deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/226:40 pm
YYZ
- SGF
1 stop15h 58m
American Airlines
Tue 9/297:43 pm
SGF
- YYZ
1 stop15h 47m
American Airlines
Deal found 4/30![American Airlines logo]()
$567
This United Airlines deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 7/246:25 am
YOW
- STL
1 stop10h 21m
United Airlines
Sat 8/81:13 pm
STL
- YOW
1 stop7h 22m
United Airlines
Deal found 4/28![United Airlines logo]()
$320
This United Airlines deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 5/232:52 pm
YOW
- STL
2 stops7h 31m
United Airlines
Wed 5/276:00 am
STL
- YOW
1 stop6h 59m
United Airlines
Deal found 4/26![United Airlines logo]()
$320
This United Airlines deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 8/126:00 am
YOW
- STL
2 stops16h 22m
United Airlines
Wed 8/196:00 am
STL
- YOW
1 stop6h 59m
United Airlines
Deal found 4/30![United Airlines logo]()
$328
This Delta deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/276:30 am
YYZ
- STL
1 stop5h 02m
Delta
Sun 5/315:20 pm
STL
- YYZ
1 stop5h 38m
Delta
Deal found 4/27![Delta logo]()
$426
This Air Canada deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/93:00 pm
YYZ
- STL
1 stop6h 25m
Air Canada
Wed 6/108:40 am
STL
- YYZ
Nonstop1h 58m
Air Canada
Deal found 4/30![Air Canada logo]()
$433
This Kiwi.com deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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.
Thu 6/1112:55 pm
YYZ
- MCI
2 stops25h 05m
Multiple Airlines
Sun 6/1410:35 am
MCI
- YYZ
1 stop12h 00m
Multiple Airlines
Deal found 4/29![Multiple Airlines logo]()
$466
This Delta deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/176:10 am
YYZ
- STL
1 stop4h 19m
Delta
Sun 5/246:00 am
STL
- YYZ
1 stop5h 19m
Delta
Deal found 4/27![Delta logo]()
$426
This Delta deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/3012:09 pm
YYZ
- STL
1 stop6h 07m
Delta
Sun 5/315:20 pm
STL
- YYZ
1 stop5h 38m
Delta
Deal found 4/27![Delta logo]()
$426
This FlightHub deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/154:10 pm
YYZ
- MCI
1 stop5h 39m
WestJet
Tue 8/115:40 pm
MCI
- YYZ
1 stop4h 17m
WestJet
Deal found 4/30![WestJet logo]()
$527
This Air Canada deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/225:20 pm
YOW
- MCI
2 stops6h 58m
Air Canada
Sun 7/266:00 am
MCI
- YOW
1 stop10h 07m
Air Canada
Deal found 4/29![Air Canada logo]()
$495
This United Airlines deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/298:50 am
YYZ
- STL
1 stop4h 21m
United Airlines
Sun 5/316:00 am
STL
- YYZ
1 stop4h 49m
United Airlines
Deal found 4/27![United Airlines logo]()
$426
This Delta deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 5/296:51 pm
YUL
- STL
1 stop6h 08m
Delta
Mon 6/17:05 am
STL
- YUL
1 stop9h 38m
Delta
Deal found 4/26![Delta logo]()
$427
This FlightHub deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/306:15 am
YYZ
- MCI
1 stop6h 00m
WestJet
Fri 7/106:25 am
MCI
- YYZ
1 stop3h 54m
WestJet
Deal found 4/28![WestJet logo]()
$529
This United Airlines deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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.
Sun 5/177:00 am
YYZ
- STL
1 stop6h 47m
United Airlines
Sun 5/245:29 pm
STL
- YYZ
1 stop5h 30m
United Airlines
Deal found 4/29![United Airlines logo]()
$426
This Delta deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 6/31:34 pm
YYZ
- STL
1 stop5h 12m
Delta
Sat 6/66:04 pm
STL
- YYZ
1 stop3h 55m
Delta
Deal found 4/27![Delta logo]()
$427
This Kiwi.com deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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.
Thu 7/25:50 pm
YYZ
- MCI
2 stops24h 31m
Multiple Airlines
Sun 7/55:40 pm
MCI
- YYZ
1 stop4h 34m
Multiple Airlines
Deal found 4/26![Multiple Airlines logo]()
$588
This FlightHub deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/76:05 am
YYZ
- MCI
1 stop4h 39m
WestJet
Mon 6/154:04 pm
MCI
- YYZ
1 stop6h 10m
WestJet
Deal found 4/26![WestJet logo]()
$535
This Delta deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 5/136:30 pm
YYZ
- STL
1 stop6h 29m
Delta
Sun 5/177:05 am
STL
- YYZ
1 stop9h 10m
Delta
Deal found 4/26![Delta logo]()
$427
This United Airlines deal was found by Cheapflights users on 4/25. Clicking the “Pick Dates” 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 6/65:50 pm
YOW
- MCI
1 stop6h 48m
United Airlines
Mon 6/86:00 am
MCI
- YOW
1 stop15h 05m
United Airlines
Deal found 4/25![United Airlines logo]()
$434
This Justfly.com deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/56:15 am
YYZ
- MCI
2 stops11h 27m
WestJet
Fri 9/116:30 am
MCI
- YYZ
1 stop10h 55m
WestJet
Deal found 4/26![WestJet logo]()
$535
This Kiwi.com deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/217:00 am
YYZ
- SGF
2 stops13h 46m
Multiple Airlines
Fri 8/288:36 pm
SGF
- YYZ
1 stop19h 33m
Multiple Airlines
Deal found 4/26![Multiple Airlines logo]()
$622
This Delta deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 6/26:00 am
YUL
- STL
1 stop4h 29m
Delta
Wed 6/35:15 pm
STL
- YUL
1 stop5h 42m
Delta
Deal found 4/27![Delta logo]()
$428
This United Airlines deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 6/136:10 am
YUL
- STL
1 stop5h 24m
United Airlines
Sat 6/201:13 pm
STL
- YUL
2 stops10h 00m
United Airlines
Deal found 4/29![United Airlines logo]()
$435
This Justfly.com deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/221:40 pm
YYZ
- MCI
1 stop6h 16m
WestJet
Thu 7/3010:29 am
MCI
- YYZ
1 stop5h 50m
WestJet
Deal found 4/27![WestJet logo]()
$536
Last-minute flights from Ontario to MissouriDiscover last-minute flight deals from Ontario to Missouri. Data last updated May 1, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Missouri. Data last updated May 1, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/209:50 am
YYZ
- MCI
1 stop24h 39m
Multiple Airlines
Tue 5/262:34 pm
MCI
- YYZ
2 stops31h 11m
Multiple Airlines
Deal found 4/29![Multiple Airlines logo]()
$412
This Air Canada deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/232:40 pm
YOW
- STL
1 stop6h 45m
Air Canada
Sun 5/247:05 am
STL
- YOW
1 stop5h 00m
Air Canada
Deal found 4/28![Air Canada logo]()
$314
This United Airlines deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” 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 5/235:50 pm
YOW
- STL
1 stop6h 45m
United Airlines
Wed 5/276:00 am
STL
- YOW
1 stop9h 38m
United Airlines
Deal found 4/26![United Airlines logo]()
$320
This United Airlines deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/232:52 pm
YOW
- STL
2 stops7h 31m
United Airlines
Sun 5/246:00 am
STL
- YOW
1 stop15h 05m
United Airlines
Deal found 4/27![United Airlines logo]()
$321
This American Airlines deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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.
Mon 5/251:15 pm
YYZ
- STL
1 stop11h 39m
American Airlines
Fri 5/292:56 pm
STL
- YYZ
1 stop7h 09m
American Airlines
Deal found 4/28![American Airlines logo]()
$412
This Air Canada deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/2511:00 am
YYZ
- STL
Nonstop2h 06m
Air Canada
Fri 5/297:05 am
STL
- YYZ
Nonstop1h 51m
Air Canada
Deal found 4/28![Air Canada logo]()
$413
This American Airlines deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 5/2711:39 am
YYZ
- STL
1 stop9h 51m
American Airlines
Wed 6/107:03 am
STL
- YYZ
1 stop9h 41m
American Airlines
Deal found 4/30![American Airlines logo]()
$344
This Kiwi.com deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/279:50 am
YYZ
- STL
1 stop15h 07m
Multiple Airlines
Wed 6/35:27 pm
STL
- YYZ
2 stops29h 13m
Multiple Airlines
Deal found 4/27![Multiple Airlines logo]()
$356
This American Airlines deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 5/277:20 am
YYZ
- STL
1 stop7h 46m
American Airlines
Wed 6/39:24 am
STL
- YYZ
1 stop4h 35m
American Airlines
Deal found 4/27![American Airlines logo]()
$391
This Air Canada deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/2711:00 am
YYZ
- STL
Nonstop2h 06m
Air Canada
Wed 6/102:15 pm
STL
- YYZ
Nonstop1h 51m
Air Canada
Deal found 4/27![Air Canada logo]()
$405
This Kiwi.com deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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 5/299:50 am
YYZ
- STL
1 stop15h 07m
Multiple Airlines
Fri 6/511:24 am
STL
- YYZ
2 stops32h 31m
Multiple Airlines
Deal found 4/30![Multiple Airlines logo]()
$397
This American Airlines deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 5/301:15 pm
YYZ
- STL
1 stop8h 15m
American Airlines
Sat 6/61:43 pm
STL
- YYZ
1 stop8h 40m
American Airlines
Deal found 4/29![American Airlines logo]()
$402
One-way flights from Ontario to MissouriSearch for one-way flight options from Ontario to Missouri. Find affordable one-way fares based on user searches. Data last updated May 1, 2026.
Search for one-way flight options from Ontario to Missouri. Find affordable one-way fares based on user searches. Data last updated May 1, 2026.
This Kiwi.com deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 6/109:50 am
YYZ
- STL
1 stop14h 59m
Multiple Airlines
Deal found 4/29![Multiple Airlines logo]()
$183
This Kiwi.com deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/166:30 am
YYZ
- STL
2 stops27h 22m
Multiple Airlines
Deal found 4/29![Multiple Airlines logo]()
$184
This Air Canada deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/77:00 am
YOW
- STL
1 stop6h 06m
Air Canada
Deal found 4/27![Air Canada logo]()
$187
This United Airlines deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 6/126:25 am
YOW
- STL
1 stop15h 51m
United Airlines
Deal found 4/28![United Airlines logo]()
$190
This Kiwi.com deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 5/188:10 am
YYZ
- STL
2 stops34h 23m
Multiple Airlines
Deal found 4/28![Multiple Airlines logo]()
$190
This Kiwi.com deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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.
Thu 6/116:30 am
YYZ
- MCI
2 stops35h 51m
Multiple Airlines
Deal found 4/27![Multiple Airlines logo]()
$191
This Kiwi.com deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” 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.
Thu 6/47:00 am
YOW
- STL
2 stops28h 29m
Multiple Airlines
Deal found 4/30![Multiple Airlines logo]()
$191
This Kiwi.com deal was found by Cheapflights users on 4/28. Clicking the “Pick Dates” 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 5/206:45 am
YUL
- STL
3 stops34h 30m
Multiple Airlines
Deal found 4/28![Multiple Airlines logo]()
$193
This United Airlines deal was found by Cheapflights users on 4/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/46:25 am
YOW
- STL
1 stop10h 21m
United Airlines
Deal found 4/30![United Airlines logo]()
$194
This Kiwi.com deal was found by Cheapflights users on 4/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/27:00 am
YOW
- MCI
3 stops35h 29m
Multiple Airlines
Deal found 4/26![Multiple Airlines logo]()
$197
This American Airlines deal was found by Cheapflights users on 4/29. Clicking the “Pick Dates” 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 6/171:15 pm
YYZ
- STL
1 stop12h 01m
American Airlines
Deal found 4/29![American Airlines logo]()
$202
This Trip.com deal was found by Cheapflights users on 4/27. Clicking the “Pick Dates” 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 6/119:50 am
YYZ
- STL
1 stop15h 19m
Multiple Airlines
Deal found 4/27![Multiple Airlines logo]()
$203
Find flight deals from Ontario to Missouri
Keep the following information in mind while searching for Ontario to Missouri flight deals. Data was last updated May 1, 2026.
Round-trip from | $314 (Air Canada) |
|---|---|
One-way from | $183 (Kiwi.com) |
Popular in | March |
Cheapest in | June |
Average price | $491 |
Good round-trip deal | $485 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to Missouri that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 1, 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
OttawaSt. Louis
YOW - STL
YOWSTL
Ottawa
Tue 6/2
6:00 am-3:46 pm
2 stops10h 46m
Lambert-St Louis
Wed 6/3
6:00 am-10:05 pm
1 stop15h 05m
$320
OttawaSt. Louis
YOW - STL
YOWSTL
Ottawa
Fri 7/24
6:25 am-3:46 pm
1 stop10h 21m
Lambert-St Louis
Sat 8/8
1:13 pm-9:35 pm
1 stop7h 22m
$320
OttawaSt. Louis
YOW - STL
YOWSTL
Ottawa
Sat 5/23
2:52 pm-9:23 pm
2 stops7h 31m
Lambert-St Louis
Wed 5/27
6:00 am-1:59 pm
1 stop6h 59m
$320
OttawaSt. Louis
YOW - STL
YOWSTL
Ottawa
Wed 8/12
6:00 am-9:22 pm
2 stops16h 22m
Lambert-St Louis
Wed 8/19
6:00 am-1:59 pm
1 stop6h 59m
$328
TorontoSt. Louis
YYZ - STL
YYZSTL
Toronto Pearson Intl
Fri 5/29
9:50 am-11:57 pm
1 stop15h 07m
Lambert-St Louis
Fri 6/5
11:24 am-8:55 pm
2 stops32h 31m
$397
TorontoSt. Louis
YYZ - STL
YYZSTL
Toronto Pearson Intl
Thu 6/4
6:10 am-9:29 am
1 stop4h 19m
Lambert-St Louis
Mon 6/8
9:21 am-5:19 pm
1 stop6h 58m
$426
TorontoSt. Louis
YYZ - STL
YYZSTL
Toronto Pearson Intl
Wed 5/27
6:30 am-10:32 am
1 stop5h 02m
Lambert-St Louis
Sun 5/31
5:20 pm-11:58 pm
1 stop5h 38m
$426
TorontoSt. Louis
YYZ - STL
YYZSTL
Toronto Pearson Intl
Sun 5/17
6:10 am-9:29 am
1 stop4h 19m
Lambert-St Louis
Sun 5/24
6:00 am-12:19 pm
1 stop5h 19m
$426
TorontoSt. Louis
YYZ - STL
YYZSTL
Toronto Pearson Intl
Sat 5/30
12:09 pm-5:16 pm
1 stop6h 07m
Lambert-St Louis
Sun 5/31
5:20 pm-11:58 pm
1 stop5h 38m
$426
TorontoSt. Louis
YYZ - STL
YYZSTL
Toronto Pearson Intl
Fri 5/29
8:50 am-12:11 pm
1 stop4h 21m
Lambert-St Louis
Sun 5/31
6:00 am-11:49 am
1 stop4h 49m
$426
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.
YOW-STL
YYZ-STL
YYZ-MCI
YUL-STL
YOW-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
CAON-USMO
YOW-STL
YYZ-STL
YYZ-MCI
YUL-STL
How far ahead should I book a flight from Region of Ontario to Missouri?
To ensure you get the cheapest price possible for a flight from Region of Ontario to Missouri, you should look to book at least 67 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.
What is the cheapest month to book a flight from Region of Ontario to Missouri?
Currently, December is the cheapest month in which you can book a flight from Region of Ontario to Missouri (average of $168). Flying from Region of Ontario to Missouri in April is currently the most expensive (average of $356). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
What is the cheapest time of day to fly from ON to MO?
Find hourly flight availability from Ontario to Missouri. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated May 1, 2026.
Unlike in the evening, when flights are generally more expensive, you can save up to 51% on flights from Region of Ontario to Missouri by exploring options for tickets in the morning.
Weekly flight availability from Region of Ontario to Missouri
Explore weekly flight availability from Ontario to Missouri. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated May 1, 2026.
The most flights from CAON to USMO are scheduled on a Monday (4 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (2 on average).
How much does it cost to fly round-trip from Region of Ontario to Missouri?
Reviews of airlines servicing Missouri
Get insights into the airlines that provide service to Missouri. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Missouri. Reviews last updated May 1, 2026.
Peruse reviews from past customers who have flown with Delta,United Airlines, andWestJet from Ontario to Missouri to help guide your decision. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.8
Food
7.2
Boarding
8.1
Crew
8.5
Comfort
7.9
Overall
7.9
Reviews
1 / 20
6.0
GoodJim,Nov 2025
AVL - ATL
Entertainment
7.8
Food
7.2
Boarding
8.1
Crew
8.5
Comfort
7.9
Overall
7.9
Reviews
1 / 20
6.0
GoodJim,Nov 2025
AVL - ATL
Entertainment
7.8
Food
7.2
Boarding
8.1
Crew
8.5
Comfort
7.9
Overall
7.9
Reviews
1 / 20
6.0
GoodJim,Nov 2025
AVL - ATL
Entertainment
7.8
Food
7.2
Boarding
8.1
Crew
8.5
Comfort
7.9
Overall
7.9
Reviews
1 / 20
6.0
GoodJim,Nov 2025
AVL - ATL
Entertainment
7.8
Food
7.2
Boarding
8.1
Crew
8.5
Comfort
7.9
Overall
7.9
Reviews
1 / 20
6.0
GoodJim,Nov 2025
AVL - ATL
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.
Browse thousands of different options on Cheapflights for your next trip
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Alternative routes for Ontario to Missouri
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Missouri by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Ontario to Missouri by cabin class
Find flights from Ontario to Missouri, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Ontario and Missouri flights
Browse other Ontario and Missouri flight options. Last updated on May 1, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Find a return flight route from Missouri
Find the right flight back to Ontario after your stay in Missouri
Ontario to Missouri flights
Consider these flights traveling from Ontario to Missouri.
Top 4 airlines flying from Ontario to Missouri
Discover the top 4 airlines that operate flights from Ontario to Missouri. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 1, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$256 | Average$498 | FlexibilityNo cancel fee | On-time67% | |
| Cheapest$428 | Average$696 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$443 | Average$585 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$530 | Average$721 | FlexibilityNo cancel fee | On-time60% |