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Missouri

$174+ 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 10/25. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — STL
août 5 — août 121
mar. 8/5
mar. 8/12
1 adult, Economy
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Cheap flight deals from Ontario to Missouri

Keep the following information in mind while searching for Ontario to Missouri flight deals. Data was last updated juillet 31, 2025.

Round-trip from

$326
(American Airlines)

One-way from

$174
(Kiwi.com)

Popular in

December

Cheapest in

October

Average price

$598

Good round-trip deal

$576 or less

Good one-way deal

$345 or less
From Ontario to Missouri
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One-way flight from Ontario to Missouri
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Highest demand for flights based on searches. 6% potential increase in price ($36 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($11 potential savings vs. average RT price).
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Average for round-trip flights in July 2025
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Price to beat on a round-trip flight from Ontario to Missouri.
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Price to beat on a one-way flight from Ontario to Missouri.
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Find flight deals from Ontario to Missouri

Cheapest flights from Ontario to Missouri
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 juillet 31, 2025.

This American Airlines deal was found by Cheapflights users on 7/29. 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.
sam. 11/84:44 pmYYZ - STL
1 stop8h 12mAmerican Airlines
sam. 11/156:00 amSTL - YYZ
1 stop9h 04mAmerican Airlines
Deal found 7/29$321
This American Airlines deal was found by Cheapflights users on 7/30. 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.
sam. 9/1312:31 pmYUL - STL
1 stop10h 22mAmerican Airlines
sam. 9/202:01 pmSTL - YUL
1 stop20h 45mAmerican Airlines
Deal found 7/30$326
This Kiwi.com deal was found by Cheapflights users on 7/30. 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.
jeu. 9/257:15 amYYZ - MCI
1 stop16h 52mMultiple Airlines
dim. 9/284:05 pmMCI - YYZ
1 stop13h 54mMultiple Airlines
Deal found 7/30$327
This Mytrip deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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.
sam. 8/306:45 amYUL - MCI
1 stop17h 08mMultiple Airlines
sam. 9/65:15 amMCI - YUL
1 stop8h 05mMultiple Airlines
Deal found 7/31$336
This Air Canada deal was found by Cheapflights users on 7/29. 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.
ven. 9/122:15 pmYYZ - STL
Nonstop2h 03mAir Canada
dim. 9/144:05 pmSTL - YYZ
Nonstop1h 55mAir Canada
Deal found 7/29$352
This Delta deal was found by Cheapflights users on 7/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 9/86:04 amYYZ - STL
1 stop11h 45mDelta
jeu. 9/116:05 amSTL - YYZ
1 stop9h 03mDelta
Deal found 7/29$407
This Delta deal was found by Cheapflights users on 7/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 9/86:00 amYUL - STL
1 stop27h 06mDelta
mar. 9/166:40 amSTL - YUL
1 stop4h 20mDelta
Deal found 7/29$408
This American Airlines deal was found by Cheapflights users on 7/31. Clicking the “Pick Dates” 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.
mar. 9/911:44 amYYZ - MCI
1 stop10h 03mAmerican Airlines
lun. 9/157:30 pmMCI - YYZ
1 stop14h 29mAmerican Airlines
Deal found 7/31$415
This Kiwi.com deal was found by Cheapflights users on 7/29. 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.
dim. 9/76:45 amYYZ - STL
2 stops18h 14mMultiple Airlines
jeu. 9/1110:35 amSTL - YYZ
1 stop9h 20mMultiple Airlines
Deal found 7/29$417
This American Airlines deal was found by Cheapflights users on 7/30. 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.
sam. 11/157:14 amYUL - MCI
2 stops12h 04mAmerican Airlines
lun. 11/176:05 amMCI - YUL
1 stop8h 06mAmerican Airlines
Deal found 7/30$424
This Air Canada deal was found by Cheapflights users on 7/29. 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.
lun. 9/86:10 pmYUL - STL
Nonstop2h 47mAir Canada
mar. 9/169:15 amSTL - YUL
1 stop6h 05mAir Canada
Deal found 7/29$427
This United Airlines deal was found by Cheapflights users on 7/30. 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.
mer. 8/276:15 amYUL - STL
1 stop10h 29mUnited Airlines
mer. 9/37:04 pmSTL - YUL
1 stop14h 36mUnited Airlines
Deal found 7/30$445

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 juillet 31, 2025.
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

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

sam. 9/13

12:31 pm-9:53 pm

1 stop10h 22m

Lambert-St Louis

sam. 9/20

2:01 pm-11:46 am

1 stop20h 45m

$326

TorontoKansas City

YYZ - MCI

YYZMCI

Toronto Pearson Intl

jeu. 9/25

7:15 am-11:07 pm

1 stop16h 52m

Kansas City

dim. 9/28

4:05 pm-6:59 am

1 stop13h 54m

$327

MontrealKansas City

YUL - MCI

YULMCI

Montreal Pierre Elliott Trudeau Intl

sam. 8/30

6:45 am-10:53 pm

1 stop17h 08m

Kansas City

sam. 9/6

5:15 am-2:20 pm

1 stop8h 05m

$336

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

ven. 9/12

2:15 pm-3:18 pm

Nonstop2h 03m

Lambert-St Louis

dim. 9/14

4:05 pm-7:00 pm

Nonstop1h 55m

$352

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

ven. 9/5

3:11 pm-11:30 am

1 stop21h 19m

Lambert-St Louis

lun. 9/8

7:59 pm-12:32 pm

1 stop15h 33m

$354

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

lun. 9/8

6:04 am-4:49 pm

1 stop11h 45m

Lambert-St Louis

jeu. 9/11

6:05 am-4:08 pm

1 stop9h 03m

$407

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

lun. 9/8

6:00 am-8:06 am

1 stop27h 06m

Lambert-St Louis

mar. 9/16

6:40 am-12:00 pm

1 stop4h 20m

$408

TorontoKansas City

YYZ - MCI

YYZMCI

Toronto Pearson Intl

mar. 9/9

11:44 am-8:47 pm

1 stop10h 03m

Kansas City

lun. 9/15

7:30 pm-10:59 am

1 stop14h 29m

$415

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

dim. 9/7

6:45 am-11:59 pm

2 stops18h 14m

Lambert-St Louis

jeu. 9/11

10:35 am-8:55 pm

1 stop9h 20m

$417

MontrealKansas City

YUL - MCI

YULMCI

Montreal Pierre Elliott Trudeau Intl

sam. 11/15

7:14 am-6:18 pm

2 stops12h 04m

Kansas City

lun. 11/17

6:05 am-3:11 pm

1 stop8h 06m

$424

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/30

Showing 1-10 of 52 results
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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.
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

What is the cheapest month to book a flight from Region of Ontario to Missouri?

Currently, August is the cheapest month in which you can book a flight from Region of Ontario to Missouri (average of $311). Flying from Region of Ontario to Missouri in March 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 juillet 31, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Region of Ontario to Missouri as you normally would.

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 juillet 31, 2025.

The most flights from CAON to USMO are scheduled on a Wednesday (4 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (2 on average).

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 juillet 31, 2025.
Peruse reviews from past customers who have flown with Alaska Airlines, Delta, and United Airlines 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.
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,Jul 2025

YEG - SEA

Alaska airline excellent airline pilot smooth, landing, crew staff very nice friendly behave
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,Jul 2025

YEG - SEA

Alaska airline excellent airline pilot smooth, landing, crew staff very nice friendly behave
Delta
8.0
Very good
7,981 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,Jul 2025

YEG - SEA

Alaska airline excellent airline pilot smooth, landing, crew staff very nice friendly behave
United Airlines
7.4
Good
8,900 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,Jul 2025

YEG - SEA

Alaska airline excellent airline pilot smooth, landing, crew staff very nice friendly behave
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,Jul 2025

YEG - SEA

Alaska airline excellent airline pilot smooth, landing, crew staff very nice friendly behave
WestJet
7.2
Good
2,978 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,Jul 2025

YEG - SEA

Alaska airline excellent airline pilot smooth, landing, crew staff very nice friendly behave

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.

  • What are the cheapest airlines to fly from Region of Ontario to Missouri one-way?

    To fly one-way, consider booking your trip with American Airlines, which is currently one of the cheapest options available, starting at $190. Iberia flights start at $197 while deals on Air Canada start at $210 one-way.

  • Can I find deals for flights from Ontario to Missouri that include hotel bookings?

    Yes. In addition to deals on Ontario to Missouri flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Missouri?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Missouri.

  • Can I find deals for business class flights from Ontario to Missouri?

    Yes. Cheapflights offers flight deals from Ontario to Missouri by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Region of Ontario to Missouri?

    Currently, August is the cheapest month in which you can book a flight from Region of Ontario to Missouri (average of $311). Flying from Region of Ontario to Missouri in March 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.

See more FAQs

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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.
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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 juillet 31, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$324Average$491FlexibilityNo cancel feeOn-time67%
DeltaCheapest$400Average$505FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$421Average$550FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$449Average$697FlexibilityNo cancel feeOn-time69%

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