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Ontario

$111+ 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 7/28. Fares are subject to change and may not be available on all flights or dates of travel.
MCI — ONT
Jul 28 — Aug 41
Tue 7/28
Tue 8/4
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 June 28, 2026.

This Kiwi.com deal was found by Cheapflights users on 6/24. 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 8/48:08 pm
STL
-
ONT
1 stop15h 56m
Frontier
Tue 8/116:00 am
ONT
-
STL
1 stop11h 23m
Frontier
Deal found 6/24$221
This Kiwi.com deal was found by Cheapflights users on 6/24. 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 8/37:10 pm
STL
-
ONT
1 stop14h 53m
Frontier
Wed 8/510:49 am
ONT
-
STL
1 stop6h 34m
Frontier
Deal found 6/24$234
This Kiwi.com deal was found by Cheapflights users on 6/23. 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.
Sat 8/81:45 pm
MCI
-
ONT
1 stop12h 05m
Frontier
Wed 8/125:08 pm
ONT
-
MCI
1 stop20h 39m
Frontier
Deal found 6/23$240
This Expedia deal was found by Cheapflights users on 6/25. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/51:45 pm
MCI
-
ONT
1 stop12h 05m
Frontier
Sat 8/86:00 am
ONT
-
MCI
1 stop5h 00m
Frontier
Deal found 6/25$244
This Frontier deal was found by Cheapflights users on 6/28. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/151:45 pm
MCI
-
ONT
1 stop12h 05m
Frontier
Sat 8/223:40 pm
ONT
-
MCI
1 stop22h 22m
Frontier
Deal found 6/28$245
This Frontier deal was found by Cheapflights users on 6/24. 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 8/111:45 pm
MCI
-
ONT
1 stop12h 05m
Frontier
Wed 8/126:00 am
ONT
-
MCI
1 stop5h 00m
Frontier
Deal found 6/24$247
This Frontier deal was found by Cheapflights users on 6/24. 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.
Wed 7/221:45 pm
MCI
-
ONT
1 stop12h 05m
Frontier
Wed 7/296:00 am
ONT
-
MCI
1 stop5h 00m
Frontier
Deal found 6/24$248
This Travelocity deal was found by Cheapflights users on 6/24. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/32:17 pm
MCI
-
ONT
1 stop11h 38m
Frontier
Tue 11/102:35 pm
ONT
-
MCI
1 stop20h 47m
Frontier
Deal found 6/24$250
This Frontier deal was found by Cheapflights users on 6/23. 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 7/141:45 pm
MCI
-
ONT
1 stop12h 05m
Frontier
Sat 7/186:00 am
ONT
-
MCI
1 stop5h 00m
Frontier
Deal found 6/23$252
This Booking.com deal was found by Cheapflights users on 6/23. 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 7/211:45 pm
MCI
-
ONT
1 stop22h 19m
Frontier
Sat 7/256:00 am
ONT
-
MCI
1 stop5h 00m
Frontier
Deal found 6/23$256
This Frontier deal was found by Cheapflights users on 6/23. 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 7/211:45 pm
MCI
-
ONT
1 stop12h 05m
Frontier
Tue 7/286:00 am
ONT
-
MCI
1 stop5h 00m
Frontier
Deal found 6/23$257
This Booking.com deal was found by Cheapflights users on 6/24. 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 8/51:45 pm
MCI
-
ONT
1 stop22h 19m
Frontier
Wed 8/197:56 pm
ONT
-
MCI
1 stop15h 24m
Frontier
Deal found 6/24$258

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 June 28, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$221
(Kiwi.com)

One-way from

$111
(Trip.com)

Popular in

June

Cheapest in

September

Average price

$456
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. 10% potential increase in price ($46 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($7 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 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 June 28, 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

Price

Cheapest round-trip

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Tue 8/4

8:08 pm-11:50 pm

1 stop5h 42m

Ontario

Thu 8/13

10:49 am-7:23 pm

1 stop6h 34m

$276

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Wed 10/14

6:13 am-1:21 pm

1 stop9h 08m

Ontario

Wed 10/14

5:30 pm-5:18 pm

1 stop21h 48m

$371

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Wed 10/14

6:40 am-12:30 pm

1 stop7h 50m

Ontario

Wed 10/14

5:05 pm-12:21 am

1 stop5h 16m

$371

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Wed 11/4

6:40 am-12:30 pm

1 stop7h 50m

Ontario

Wed 11/4

5:05 pm-12:21 am

1 stop5h 16m

$371

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Tue 9/8

2:53 pm-9:51 am

1 stop20h 58m

Ontario

Wed 9/16

6:02 am-11:59 pm

1 stop15h 57m

$371

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Sat 8/8

11:20 am-6:15 pm

2 stops8h 55m

Ontario

Wed 8/12

12:59 pm-12:35 am

2 stops9h 36m

$381

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Thu 8/20

10:20 am-3:05 pm

2 stops6h 45m

Ontario

Mon 8/24

5:15 am-3:35 pm

2 stops8h 20m

$387

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Sat 8/8

5:15 am-9:35 am

1 stop6h 20m

Ontario

Thu 8/13

12:35 pm-9:55 pm

2 stops7h 20m

$390
Quickest round-trip

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Thu 11/26

7:40 pm-11:48 pm

1 stop6h 08m

Ontario

Tue 12/1

5:05 pm-12:21 am

1 stop5h 16m

$392

ColumbiaOntario

COU - ONT

COUONT

Columbia Regional

Thu 7/9

10:49 am-10:37 pm

2 stops13h 48m

Ontario

Thu 12/24

11:59 pm-10:33 am

1 stop8h 34m

$394

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/26

Showing 1-10 of 60 resultsSorted by cheapest first
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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, 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.

  • 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 $276, Frontier can have you in Ontario from Missouri in 5h 42m. The distance from Missouri to Ontario is about 1541 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 $79. Users have also found prices from $128 and $142 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, 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.

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 4 airlines flying from Missouri to Ontario

Discover the top 4 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 June 28, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$94Average$277FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$201Average$421FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$247Average$429FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$269Average$435FlexibilityNo cancel feeOn-time63%

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