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Missouri

$66+ Cheap flights from Ontario (ONT) 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 10/22. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — STL
Oct 17 — Oct 241
Fri 10/17
Fri 10/24
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 September 17, 2025.

Round-trip from

$143
(Priceline)

One-way from

$66
(Trip.com)

Popular in

February

Cheapest in

September

Average price

$228
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. 9% potential increase in price ($32 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($7 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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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 September 17, 2025.

This Mytrip deal was found by Cheapflights users on 9/15. 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.
Fri 10/310:28 pmONT - STL
1 stop15h 35mFrontier
Sun 10/57:55 pmSTL - ONT
1 stop13h 58mFrontier
Deal found 9/15$143
This Mytrip deal was found by Cheapflights users on 9/14. 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.
Thu 11/136:53 amONT - MCI
1 stop10h 40mFrontier
Sat 11/158:28 pmMCI - ONT
1 stop16h 42mFrontier
Deal found 9/14$143
This Frontier deal was found by Cheapflights users on 9/16. 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 10/188:00 amONT - STL
1 stop5h 56mFrontier
Thu 10/2310:17 amSTL - ONT
1 stop7h 15mFrontier
Deal found 9/16$144
This Booking.com deal was found by Cheapflights users on 9/15. 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 10/18:59 pmONT - MCI
1 stop14h 49mFrontier
Mon 10/63:01 pmMCI - ONT
1 stop9h 12mFrontier
Deal found 9/15$144
This Booking.com deal was found by Cheapflights users on 9/14. 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 9/238:59 pmONT - STL
1 stop10h 07mFrontier
Tue 9/307:55 pmSTL - ONT
1 stop25h 59mFrontier
Deal found 9/14$145
This Booking.com deal was found by Cheapflights users on 9/15. 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 9/268:59 pmONT - STL
1 stop10h 07mFrontier
Mon 9/299:29 pmSTL - ONT
1 stop26h 27mFrontier
Deal found 9/15$146
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/88:00 amONT - STL
1 stop5h 56mFrontier
Tue 11/117:45 pmSTL - ONT
1 stop6h 05mFrontier
Deal found 9/15$155
This Booking.com deal was found by Cheapflights users on 9/15. 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.
Sun 9/288:59 pmONT - STL
1 stop10h 07mFrontier
Tue 9/307:55 pmSTL - ONT
1 stop25h 59mFrontier
Deal found 9/15$157
This Trip.com deal was found by Cheapflights users on 9/16. 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 10/96:05 amONT - STL
1 stop27h 38mFrontier
Tue 10/147:52 pmSTL - ONT
1 stop5h 58mFrontier
Deal found 9/16$158
This Booking.com deal was found by Cheapflights users on 9/15. 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.
Sat 10/48:59 pmONT - MCI
1 stop14h 49mFrontier
Mon 10/63:01 pmMCI - ONT
1 stop9h 12mFrontier
Deal found 9/15$168
This Priceline deal was found by Cheapflights users on 9/15. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/910:30 amONT - MCI
1 stop7h 23mFrontier
Mon 10/138:38 pmMCI - ONT
1 stop5h 12mFrontier
Deal found 9/15$170
This Booking.com deal was found by Cheapflights users on 9/15. 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.
Sat 10/117:04 amONT - MCI
1 stop8h 51mFrontier
Mon 10/138:38 pmMCI - ONT
1 stop5h 12mFrontier
Deal found 9/15$171

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 September 17, 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

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Thu 11/13

6:00 am-1:57 pm

1 stop5h 57m

Lambert-St Louis

Mon 11/17

7:45 pm-11:50 pm

1 stop6h 05m

$143

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Tue 10/14

7:04 am-9:07 am

1 stop24h 03m

Lambert-St Louis

Tue 10/21

7:52 pm-11:50 pm

1 stop5h 58m

$143

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Sat 10/18

8:00 am-3:56 pm

1 stop5h 56m

Lambert-St Louis

Tue 10/21

7:52 pm-11:50 pm

1 stop5h 58m

$144

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Sat 11/8

8:00 am-3:56 pm

1 stop5h 56m

Lambert-St Louis

Tue 11/11

7:45 pm-11:50 pm

1 stop6h 05m

$156

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Thu 10/9

6:05 am-11:43 am

1 stop27h 38m

Lambert-St Louis

Tue 10/14

7:52 pm-11:50 pm

1 stop5h 58m

$158

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Thu 10/2

8:59 pm-1:48 pm

1 stop14h 49m

Kansas City

Mon 10/6

3:01 pm-10:13 pm

1 stop9h 12m

$187

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Fri 10/24

10:47 pm-3:56 pm

1 stop15h 09m

Lambert-St Louis

Sun 10/26

7:52 pm-9:35 am

1 stop15h 43m

$190

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Wed 10/22

6:53 am-9:07 am

1 stop24h 14m

Lambert-St Louis

Sun 10/26

10:17 am-3:32 pm

1 stop7h 15m

$201

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Thu 10/23

10:30 am-7:53 pm

1 stop7h 23m

Kansas City

Sun 10/26

4:00 pm-11:47 am

2 stops21h 47m

$220

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Fri 10/10

11:53 am-5:55 pm

1 stop28h 02m

Kansas City

Mon 10/13

8:38 pm-11:50 pm

1 stop5h 12m

$223

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 60 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 Ontario to Missouri?

Currently, August is the cheapest month in which you can book a flight from Ontario to Missouri (average of $311). Flying from 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 ONT 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 September 17, 2025.

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

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 September 17, 2025.
See what other customers who have flown with Southwest, Delta, and United Airlines from Ontario to Missouri have to say. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,242 reviews

Entertainment

7.5

Food

7.0

Overall

8.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Southwest
8.0
Very good
4,242 reviews
Southwest
8.0
Very good
4,242 reviews

Entertainment

7.5

Food

7.0

Overall

8.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Delta
8.0
Very good
7,957 reviews
Southwest
8.0
Very good
4,242 reviews

Entertainment

7.5

Food

7.0

Overall

8.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
United Airlines
7.4
Good
8,924 reviews
Southwest
8.0
Very good
4,242 reviews

Entertainment

7.5

Food

7.0

Overall

8.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,242 reviews

Entertainment

7.5

Food

7.0

Overall

8.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Frontier
5.8
Fair
3,174 reviews
Southwest
8.0
Very good
4,242 reviews

Entertainment

7.5

Food

7.0

Overall

8.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

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 airport do you fly from for flights from Ontario to Missouri?

    Located just 3.1 mi from the city center, Ontario (ONT) is the airport most travelers will use when flying to Missouri from Ontario.

  • How long is the flight from Ontario to Missouri?

    Airlines like Frontier, Alaska Airlines, and American Airlines fly from Ontario to Missouri in about 5h 57m. The time it takes to get you to your destination can typically vary by up to 13h 54m. The distance between Ontario and Missouri is about 1541 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $72. Users have also found prices from $118 and $129 on Alaska Airlines and Delta, respectively.

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

    The most popular route from Ontario to Missouri is Ontario - Kansas City. You may also consider Ontario - Lambert-St Louis or Ontario - Springfield-Branson.

  • 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 Ontario to Missouri?

    Currently, August is the cheapest month in which you can book a flight from Ontario to Missouri (average of $311). Flying from 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 5 airlines flying from Ontario to Missouri

Discover the top 5 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 September 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$121Average$240FlexibilityNo cancel feeOn-time62%
DeltaCheapest$134Average$386FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$247Average$424FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$268Average$451FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$278Average$477FlexibilityNo cancel feeOn-time69%

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