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$60+ 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 4/25. Fares are subject to change and may not be available on all flights or dates of travel.
STL — ONT
Mar 14 — Mar 211
Sat 3/14
Sat 3/21
1 adult, Economy
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Cheap flight deals from Missouri to Ontario

Cheapest flights from Missouri to Ontario
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 February 12, 2026.

This Kiwi.com deal was found by Cheapflights users on 2/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/308:12 pm
STL
-
ONT
1 stop13h 19m
Frontier
Fri 5/112:59 am
ONT
-
STL
1 stop16h 13m
Frontier
Deal found 2/8$160
This Kiwi.com deal was found by Cheapflights users on 2/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/232:15 pm
MCI
-
ONT
1 stop11h 40m
Frontier
Sat 4/2512:59 am
ONT
-
MCI
1 stop10h 31m
Frontier
Deal found 2/9$167
This Kiwi.com deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/98:38 pm
MCI
-
ONT
1 stop29h 21m
Multiple Airlines
Tue 3/172:23 pm
ONT
-
MCI
1 stop24h 46m
Multiple Airlines
Deal found 2/10$177
This Kiwi.com deal was found by Cheapflights users on 2/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/178:06 pm
STL
-
ONT
1 stop19h 22m
Frontier
Fri 4/175:33 pm
ONT
-
STL
1 stop23h 39m
Frontier
Deal found 2/9$179
This Mytrip deal was found by Cheapflights users on 2/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/44:39 pm
MCI
-
ONT
1 stop6h 55m
Frontier
Mon 3/96:15 am
ONT
-
MCI
1 stop11h 38m
Frontier
Deal found 2/9$179
This Kiwi.com deal was found by Cheapflights users on 2/11. 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.
Thu 4/302:15 pm
MCI
-
ONT
1 stop11h 40m
Frontier
Sun 5/312:59 am
ONT
-
MCI
1 stop10h 31m
Frontier
Deal found 2/11$186
This Kiwi.com deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/108:06 pm
STL
-
ONT
2 stops29h 53m
Frontier
Tue 3/176:15 am
ONT
-
STL
1 stop25h 34m
Frontier
Deal found 2/10$190
This Frontier deal was found by Cheapflights users on 2/11. 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.
Mon 4/202:15 pm
MCI
-
ONT
1 stop11h 40m
Frontier
Thu 4/2312:59 am
ONT
-
MCI
1 stop10h 31m
Frontier
Deal found 2/11$190
This Booking.com deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/108:16 pm
STL
-
ONT
1 stop5h 40m
Frontier
Sun 4/126:20 am
ONT
-
STL
1 stop25h 28m
Frontier
Deal found 2/10$197
This CheapOair deal was found by Cheapflights users on 2/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/210:11 pm
STL
-
ONT
1 stop17h 00m
Frontier
Mon 3/1611:17 am
ONT
-
STL
1 stop22h 58m
Frontier
Deal found 2/8$203
This Kiwi.com deal was found by Cheapflights users on 2/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/126:04 pm
MCI
-
ONT
1 stop16h 00m
Multiple Airlines
Wed 4/152:44 pm
ONT
-
MCI
1 stop6h 49m
Multiple Airlines
Deal found 2/10$203
This Kiwi.com deal was found by Cheapflights users on 2/11. 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 5/152:15 pm
MCI
-
ONT
2 stops22h 29m
Frontier
Sun 5/1712:59 am
ONT
-
MCI
1 stop10h 31m
Frontier
Deal found 2/11$208

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 February 12, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$160
(Kiwi.com)

One-way from

$60
(Trip.com)

Popular in

March

Cheapest in

September

Average price

$372
Provider with most accurate pricing for Lambert-St Louis-Los Angeles flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Los Angeles flights.
Search Deals
From Missouri to Ontario
Search Deals
One-way flight from Missouri to Ontario
Search Deals
Highest demand for flights based on searches. 3% potential increase in price ($14 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2026
Search Deals

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 February 12, 2026.
Use the filters below to find and compare flights from Missouri to Ontario that are best for you.

Fly from

Missouri

Fly to

Ontario

Route

Depart

Return

Price

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Tue 3/10

8:06 pm-9:03 pm

1 stop26h 57m

Ontario

Tue 3/17

6:15 am-9:49 am

1 stop25h 34m

$193

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Mon 2/23

8:33 pm-11:59 pm

1 stop5h 26m

Ontario

Sun 3/1

6:10 am-12:59 pm

1 stop4h 49m

$211

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Thu 4/30

11:21 am-11:24 pm

2 stops14h 03m

Ontario

Fri 5/1

12:59 am-7:12 pm

1 stop16h 13m

$218

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Mon 3/2

8:33 pm-9:34 pm

1 stop27h 01m

Ontario

Sat 3/14

6:15 am-7:55 pm

1 stop11h 40m

$220

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Fri 5/15

2:15 pm-11:55 pm

1 stop11h 40m

Ontario

Sun 5/17

5:33 pm-1:30 pm

1 stop17h 57m

$222

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Sun 4/12

6:04 pm-8:04 am

1 stop16h 00m

Ontario

Tue 4/14

12:59 am-11:33 pm

2 stops20h 34m

$226

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Mon 2/23

1:54 pm-11:59 pm

1 stop12h 05m

Ontario

Wed 2/25

8:40 am-3:53 pm

1 stop5h 13m

$232

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Sun 4/12

8:28 pm-11:56 pm

1 stop5h 28m

Ontario

Wed 4/22

12:59 am-1:30 pm

1 stop10h 31m

$240

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Sun 4/26

2:15 pm-11:55 pm

1 stop11h 40m

Ontario

Sun 4/26

12:59 am-1:30 pm

1 stop10h 31m

$250

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Fri 3/20

8:12 pm-11:59 pm

1 stop5h 47m

Ontario

Mon 3/23

11:17 am-11:19 am

1 stop22h 02m

$252

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/11

Showing 1-10 of 60 results
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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.
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

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

Currently, November is the cheapest month in which you can book a flight from Missouri to Ontario (average of $67). Flying from Missouri to Ontario in December is currently the most expensive (average of $169). 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.

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.

  • What airport do you fly into for flights to Ontario from Missouri?

    For a flight from Missouri to Ontario, you will be flying into Ontario. Ontario (ONT) is just 3.1 mi from the center of the city.

  • How long is the flight from Missouri to Ontario?

    For as low as $289, Frontier can have you in Ontario from Missouri in 6h 36m. The distance from Missouri to Ontario is about 1372 mi. This flight may include one or multiple stops.

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

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $67. Users have also found prices from $92 and $118 on American Airlines and Southwest, respectively.

  • What are the most popular routes from Missouri to Ontario?

    When deciding which route to take from Missouri to Ontario consider Kansas City - Ontario, Lambert-St Louis - Ontario or Springfield-Branson - Ontario as they are the most popular.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Missouri to Ontario 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 Missouri to Ontario?

    Currently, November is the cheapest month in which you can book a flight from Missouri to Ontario (average of $67). Flying from Missouri to Ontario in December is currently the most expensive (average of $169). 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 Missouri to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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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 February 12, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$128Average$241FlexibilityNo cancel feeOn-time62%
DeltaCheapest$171Average$362FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$253Average$427FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$264Average$421FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$289Average$394FlexibilityNo cancel feeOn-time63%

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