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$62+ 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 2/11. Fares are subject to change and may not be available on all flights or dates of travel.
STL — ONT
dic. 6 — dic. 131
sáb. 12/6
sáb. 12/13
1 adult, Economy
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Cheap flight deals from Missouri to Ontario

Keep the following information in mind while searching for Missouri to Ontario flight deals. Data was last updated noviembre 6, 2025.

Most accurate provider

Justfly.com
3 stars

Most trusted provider

Justfly.com
3 stars

Round-trip from

$130
(CheapOair)

One-way from

$62
(Trip.com)

Popular in

March

Cheapest in

September

Average price

$406
Provider with most accurate pricing for Lambert-St Louis-Los Angeles flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Los Angeles flights.
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From Missouri to Ontario
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One-way flight from Missouri to Ontario
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Highest demand for flights based on searches. 3% potential increase in price ($14 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
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Average for round-trip flights in November 2025
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Find 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 noviembre 6, 2025.

This CheapOair deal was found by Cheapflights users on 11/4. 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.
mié. 11/197:45 pmSTL - ONT
1 stop17h 26mFrontier
jue. 11/2712:58 amONT - STL
1 stop7h 04mFrontier
Deal found 11/4$134
This Frontier deal was found by Cheapflights users on 11/4. 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.
jue. 11/277:57 pmSTL - ONT
1 stop6h 00mFrontier
sáb. 12/66:15 amONT - STL
1 stop27h 57mFrontier
Deal found 11/4$135
This Booking.com deal was found by Cheapflights users on 11/4. 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.
mié. 11/196:49 pmMCI - ONT
1 stop18h 22mFrontier
lun. 11/2412:58 amONT - MCI
1 stop16h 36mFrontier
Deal found 11/4$135
This CheapOair deal was found by Cheapflights users on 11/3. 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.
mié. 11/197:45 pmSTL - ONT
1 stop17h 26mFrontier
sáb. 11/2212:58 amONT - STL
1 stop16h 00mFrontier
Deal found 11/3$137
This Mytrip deal was found by Cheapflights users on 11/3. 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.
mié. 11/196:49 pmMCI - ONT
1 stop18h 22mFrontier
sáb. 11/2212:58 amONT - MCI
1 stop16h 35mFrontier
Deal found 11/3$137
This CheapOair deal was found by Cheapflights users on 11/5. 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.
mié. 12/37:43 pmSTL - ONT
1 stop17h 26mFrontier
sáb. 12/66:15 amONT - STL
1 stop27h 57mFrontier
Deal found 11/5$138
This Mytrip deal was found by Cheapflights users on 11/5. 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.
jue. 11/209:54 pmSTL - ONT
1 stop18h 32mFrontier
vie. 11/2812:58 amONT - STL
1 stop7h 04mFrontier
Deal found 11/5$140
This Frontier deal was found by Cheapflights users on 11/4. 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.
sáb. 11/227:43 pmSTL - ONT
1 stop6h 14mFrontier
jue. 11/2712:58 amONT - STL
1 stop7h 04mFrontier
Deal found 11/4$141
This Mytrip deal was found by Cheapflights users on 11/4. 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.
vie. 11/218:28 pmMCI - ONT
1 stop5h 29mFrontier
lun. 11/2412:58 amONT - MCI
1 stop16h 36mFrontier
Deal found 11/4$141
This CheapOair deal was found by Cheapflights users on 11/4. 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.
mié. 12/37:43 pmSTL - ONT
1 stop17h 26mFrontier
dom. 12/76:15 amONT - STL
1 stop27h 57mFrontier
Deal found 11/4$142
This Booking.com deal was found by Cheapflights users on 11/4. 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.
sáb. 11/228:28 pmMCI - ONT
1 stop5h 29mFrontier
lun. 11/2412:58 amONT - MCI
1 stop16h 36mFrontier
Deal found 11/4$142
This Mytrip deal was found by Cheapflights users on 11/5. 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.
jue. 12/48:09 pmMCI - ONT
1 stop20h 16mFrontier
dom. 12/74:01 pmONT - MCI
1 stop25h 49mFrontier
Deal found 11/5$146

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 noviembre 6, 2025.
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

vie. 12/5

7:43 pm-2:25 pm

1 stop20h 42m

Ontario

dom. 12/7

6:15 am-12:12 pm

1 stop27h 57m

$138

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

jue. 12/4

1:16 pm-9:17 pm

1 stop10h 01m

Ontario

dom. 12/7

6:15 am-12:12 pm

1 stop27h 57m

$138

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

dom. 1/11

8:46 pm-11:59 pm

1 stop29h 13m

Ontario

dom. 1/18

6:00 am-7:51 pm

1 stop11h 51m

$138

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

sáb. 11/22

7:43 pm-11:57 pm

1 stop6h 14m

Ontario

dom. 11/23

12:58 am-10:02 am

1 stop7h 04m

$141

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

sáb. 11/22

7:43 pm-11:28 am

1 stop17h 45m

Ontario

vie. 11/28

7:48 pm-10:02 am

1 stop12h 14m

$144

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

jue. 12/4

8:09 pm-2:25 pm

1 stop20h 16m

Ontario

dom. 12/7

4:01 pm-7:50 pm

1 stop25h 49m

$146

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

jue. 11/20

7:57 pm-11:57 pm

1 stop6h 00m

Ontario

sáb. 11/22

12:58 am-6:58 pm

1 stop16h 00m

$149

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

mié. 11/26

8:28 pm-11:57 pm

1 stop5h 29m

Ontario

dom. 11/30

12:58 am-7:33 pm

1 stop16h 35m

$185

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

sáb. 11/22

7:43 pm-11:57 pm

1 stop6h 14m

Ontario

vie. 11/28

12:58 am-10:02 am

1 stop7h 04m

$198

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

jue. 11/20

9:54 pm-2:26 pm

1 stop18h 32m

Ontario

dom. 11/30

5:06 pm-9:09 pm

1 stop26h 03m

$211

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/6

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 $68). Flying from Missouri to Ontario in March is currently the most expensive (average of $146). 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 MO to ONT?

Find hourly flight availability from Missouri to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated noviembre 6, 2025.

When flying from Missouri to Ontario, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 46% versus a flight in the morning.

What is the cheapest day to fly from Missouri to Ontario?

Use this chart to determine the cheapest time to fly round-trip from Missouri to Ontario. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Missouri to Ontario flight should consider departing on Wednesday evenings when fares are most often at their lowest. Monday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

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 $264, Frontier can have you in Ontario from Missouri in 5h 32m. The distance from Missouri to Ontario is about 1442 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 $62. Users have also found prices from $143 and $164 on Alaska Airlines and Delta, 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 $68). Flying from Missouri to Ontario in March is currently the most expensive (average of $146). 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 noviembre 6, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$108Average$236FlexibilityNo cancel feeOn-time62%
DeltaCheapest$171Average$362FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$264Average$426FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$284Average$427FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$290Average$399FlexibilityNo cancel feeOn-time63%

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