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Missouri

$60+ 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 3/10. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — STL
Mar 14 — Mar 211
Sat 3/14
Sat 3/21
1 adult, Economy
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Cheap 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 February 12, 2026.

This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/112:59 am
ONT
-
STL
1 stop16h 13m
Frontier
Mon 5/49:55 pm
STL
-
ONT
1 stop17h 45m
Frontier
Deal found 2/9$162
This Frontier deal was found by Cheapflights users on 2/7. 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 2/258:40 am
ONT
-
STL
1 stop5h 13m
Frontier
Sat 2/282:51 pm
STL
-
ONT
1 stop11h 08m
Frontier
Deal found 2/7$169
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 4/2412:59 am
ONT
-
MCI
1 stop11h 07m
Frontier
Mon 4/272:15 pm
MCI
-
ONT
1 stop11h 40m
Frontier
Deal found 2/11$179
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/266:05 am
ONT
-
MCI
1 stop12h 24m
Frontier
Mon 3/28:33 pm
MCI
-
ONT
1 stop27h 01m
Frontier
Deal found 2/9$180
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.
Tue 3/38:40 am
ONT
-
STL
1 stop29h 13m
Frontier
Thu 3/510:11 pm
STL
-
ONT
1 stop11h 55m
Frontier
Deal found 2/11$184
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.
Sun 4/2612:59 am
ONT
-
MCI
1 stop10h 31m
Frontier
Thu 4/302:15 pm
MCI
-
ONT
1 stop11h 40m
Frontier
Deal found 2/11$186
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/257:17 pm
ONT
-
STL
1 stop24h 09m
Frontier
Sun 3/110:11 pm
STL
-
ONT
1 stop21h 37m
Frontier
Deal found 2/10$190
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2212:59 am
ONT
-
MCI
1 stop10h 31m
Frontier
Mon 4/272:15 pm
MCI
-
ONT
1 stop11h 40m
Frontier
Deal found 2/10$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.
Sun 3/16:10 am
ONT
-
MCI
1 stop4h 49m
Frontier
Mon 3/28:33 pm
MCI
-
ONT
1 stop27h 01m
Frontier
Deal found 2/10$192
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 3/57:22 pm
ONT
-
STL
1 stop13h 57m
Frontier
Sun 3/86:19 pm
STL
-
ONT
1 stop15h 47m
Frontier
Deal found 2/11$193
This Booking.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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/172:23 pm
ONT
-
STL
1 stop18h 56m
Frontier
Wed 3/188:12 pm
STL
-
ONT
1 stop5h 47m
Frontier
Deal found 2/9$197
This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/2412:59 am
ONT
-
STL
1 stop16h 13m
Frontier
Sat 5/28:12 pm
STL
-
ONT
1 stop5h 43m
Frontier
Deal found 2/9$198

Find flight deals from Ontario to Missouri

Keep the following information in mind while searching for Ontario to Missouri flight deals. Data was last updated February 12, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$162
(Trip.com)

One-way from

$60
(Trip.com)

Popular in

February

Cheapest in

October

Average price

$425
Provider with most accurate pricing for Los Angeles-Lambert-St Louis flight deals.
Search Deals
Provider most trusted by Cheapflights users for Los Angeles-Lambert-St Louis flights.
Search Deals
From Ontario to Missouri
Search Deals
One-way flight from Ontario to Missouri
Search Deals
Highest demand for flights based on searches. 5% potential increase in price ($23 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($4 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 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 February 12, 2026.
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

Tue 3/3

8:40 am-3:53 pm

1 stop29h 13m

Lambert-St Louis

Thu 3/5

10:11 pm-8:06 am

1 stop11h 55m

$184

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Thu 4/23

12:59 am-7:12 pm

1 stop16h 13m

Lambert-St Louis

Mon 4/27

9:55 pm-6:34 pm

1 stop22h 39m

$190

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Sun 4/19

12:59 am-7:12 pm

1 stop16h 13m

Lambert-St Louis

Fri 4/24

9:55 pm-10:44 am

1 stop14h 49m

$190

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Tue 3/17

2:23 pm-11:19 am

1 stop18h 56m

Lambert-St Louis

Wed 3/18

8:12 pm-11:59 pm

1 stop5h 47m

$201

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Fri 2/27

9:43 pm-5:46 pm

1 stop18h 03m

Lambert-St Louis

Mon 3/2

10:11 pm-1:11 pm

1 stop17h 00m

$201

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Sun 4/19

12:59 am-7:12 pm

1 stop16h 13m

Lambert-St Louis

Thu 4/23

8:12 pm-11:55 pm

1 stop5h 43m

$201

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Fri 4/17

6:15 am-2:12 pm

1 stop5h 57m

Lambert-St Louis

Mon 4/20

8:12 pm-11:55 pm

1 stop5h 43m

$211

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Wed 2/25

8:40 am-3:44 pm

1 stop5h 04m

Kansas City

Sat 2/28

8:41 pm-11:59 pm

1 stop5h 18m

$211

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Wed 5/13

7:29 pm-1:30 pm

2 stops16h 01m

Kansas City

Sat 5/16

2:51 pm-7:31 am

1 stop18h 40m

$213

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Thu 3/5

2:08 pm-7:55 pm

1 stop27h 47m

Kansas City

Mon 3/9

8:38 pm-11:59 pm

1 stop5h 21m

$218

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/8

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, June is the cheapest month in which you can book a flight from Ontario to Missouri (average of $60). Flying from Ontario to Missouri in November is currently the most expensive (average of $149). 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.

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 February 12, 2026.
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
4,280 reviews

Overall

8.0

Food

7.0

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Southwest
8.0
Very good
4,280 reviews
Southwest
8.0
Very good
4,280 reviews

Overall

8.0

Food

7.0

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Delta
7.9
Good
8,177 reviews
Southwest
8.0
Very good
4,280 reviews

Overall

8.0

Food

7.0

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
United Airlines
7.4
Good
9,276 reviews
Southwest
8.0
Very good
4,280 reviews

Overall

8.0

Food

7.0

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
American Airlines
7.2
Good
11,267 reviews
Southwest
8.0
Very good
4,280 reviews

Overall

8.0

Food

7.0

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Frontier
5.7
Fair
3,052 reviews
Southwest
8.0
Very good
4,280 reviews

Overall

8.0

Food

7.0

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

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, American Airlines, and United Airlines fly from Ontario to Missouri in about 7h 25m. The time it takes to get you to your destination can typically vary by up to 21h 48m. The distance between Ontario and Missouri is about 1372 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • 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, June is the cheapest month in which you can book a flight from Ontario to Missouri (average of $60). Flying from Ontario to Missouri in November is currently the most expensive (average of $149). 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 February 12, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$67Average$221FlexibilityNo cancel feeOn-time62%
DeltaCheapest$98Average$374FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$247Average$418FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$256Average$459FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$268Average$440FlexibilityNo cancel feeOn-time71%

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