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Missouri

$64+ 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 2/11. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — STL
Jan 27 — Feb 31
Tue 1/27
Tue 2/3
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 December 28, 2025.

This CheapOair deal was found by Cheapflights users on 12/26. 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 12/296:00 amONT - STL
1 stop13h 25mFrontier
Mon 1/57:43 pmSTL - ONT
1 stop28h 29mFrontier
Deal found 12/26$354
This Frontier deal was found by Cheapflights users on 12/26. 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 12/316:45 amONT - MCI
1 stop11h 05mFrontier
Mon 1/58:45 pmMCI - ONT
1 stop5h 14mFrontier
Deal found 12/26$383
This CheapOair deal was found by Cheapflights users on 12/26. 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 12/296:00 amONT - STL
1 stop13h 25mFrontier
Fri 1/210:10 pmSTL - ONT
1 stop20h 21mFrontier
Deal found 12/26$388
This Gotogate deal was found by Cheapflights users on 12/26. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/306:45 amONT - STL
1 stop25h 17mFrontier
Fri 1/210:10 pmSTL - ONT
1 stop27h 11mFrontier
Deal found 12/26$401
This United Airlines deal was found by Cheapflights users on 12/26. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/2911:59 pmONT - SGF
1 stop8h 50mUnited Airlines
Mon 1/125:03 pmSGF - ONT
1 stop5h 55mUnited Airlines
Deal found 12/26$404
This Frontier deal was found by Cheapflights users on 12/26. 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 12/276:45 amONT - MCI
1 stop11h 06mFrontier
Fri 1/28:45 pmMCI - ONT
1 stop5h 14mFrontier
Deal found 12/26$407
This CheapOair deal was found by Cheapflights users on 12/26. 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.
Sat 12/275:16 pmONT - STL
1 stop26h 09mFrontier
Sun 1/410:10 pmSTL - ONT
1 stop25h 07mFrontier
Deal found 12/26$408
This Frontier deal was found by Cheapflights users on 12/26. 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 12/306:45 amONT - MCI
1 stop11h 05mFrontier
Sun 1/48:45 pmMCI - ONT
1 stop5h 14mFrontier
Deal found 12/26$432
This United Airlines deal was found by Cheapflights users on 12/27. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/315:05 amONT - COU
2 stops10h 20mUnited Airlines
Thu 1/2911:17 amCOU - ONT
2 stops13h 36mUnited Airlines
Deal found 12/27$452
This Frontier deal was found by Cheapflights users on 12/25. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/266:45 amONT - MCI
1 stop11h 05mFrontier
Fri 1/28:45 pmMCI - ONT
1 stop5h 14mFrontier
Deal found 12/25$452
This United Airlines deal was found by Cheapflights users on 12/27. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/315:05 amONT - COU
2 stops10h 20mUnited Airlines
Fri 2/2011:15 amCOU - ONT
2 stops11h 35mUnited Airlines
Deal found 12/27$477
This Expedia deal was found by Cheapflights users on 12/26. 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.
Mon 12/296:00 amONT - STL
1 stop13h 25mFrontier
Wed 12/315:19 pmSTL - ONT
1 stop5h 58mFrontier
Deal found 12/26$482

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 December 28, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$145
(Kiwi.com)

One-way from

$64
(Cheapflightsfares)

Popular in

December

Cheapest in

October

Average price

$437
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. 1% potential increase in price ($7 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 December 2025
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 December 28, 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

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Mon 1/26

6:20 am-7:51 pm

1 stop11h 31m

Kansas City

Fri 1/30

8:41 pm-11:24 pm

1 stop28h 43m

$153

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Wed 2/4

7:15 am-2:46 pm

1 stop5h 31m

Lambert-St Louis

Sat 2/7

3:46 pm-11:24 pm

1 stop9h 38m

$165

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Thu 1/22

11:04 am-9:06 pm

1 stop8h 02m

Lambert-St Louis

Mon 1/26

1:40 pm-12:20 am

1 stop12h 40m

$182

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Fri 2/6

2:28 pm-2:46 pm

2 stops22h 18m

Lambert-St Louis

Mon 2/9

9:45 pm-1:52 pm

1 stop18h 07m

$203

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Fri 1/30

6:20 am-7:51 pm

1 stop11h 31m

Kansas City

Mon 2/2

8:41 pm-12:20 am

1 stop5h 39m

$210

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Thu 2/19

6:05 am-7:33 pm

1 stop11h 28m

Kansas City

Sun 2/22

1:44 pm-11:59 pm

1 stop12h 15m

$210

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Mon 1/12

10:18 pm-2:48 pm

2 stops38h 30m

Lambert-St Louis

Sun 1/18

10:09 pm-7:37 am

1 stop11h 28m

$216

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Thu 1/15

10:18 pm-12:40 pm

1 stop12h 22m

Lambert-St Louis

Sun 1/18

10:09 pm-7:37 am

1 stop11h 28m

$217

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Mon 1/26

6:20 am-7:51 pm

1 stop11h 31m

Kansas City

Mon 2/2

8:41 pm-12:20 am

1 stop5h 39m

$222

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Fri 1/23

2:28 pm-11:33 pm

1 stop7h 05m

Kansas City

Sun 1/25

8:41 pm-2:41 pm

2 stops20h 00m

$233

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/26

Showing 1-10 of 56 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 December 28, 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
4,256 reviews

Entertainment

7.5

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.1

Food

7.0

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
4,256 reviews
Southwest
8.0
Very good
4,256 reviews

Entertainment

7.5

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.1

Food

7.0

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
8,019 reviews
Southwest
8.0
Very good
4,256 reviews

Entertainment

7.5

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.1

Food

7.0

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
9,113 reviews
Southwest
8.0
Very good
4,256 reviews

Entertainment

7.5

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.1

Food

7.0

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
11,072 reviews
Southwest
8.0
Very good
4,256 reviews

Entertainment

7.5

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.1

Food

7.0

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
5.8
Fair
3,065 reviews
Southwest
8.0
Very good
4,256 reviews

Entertainment

7.5

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.1

Food

7.0

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 5h 40m. The time it takes to get you to your destination can typically vary by up to 5h 51m. 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 - Lambert-St Louis. You may also consider Ontario - Kansas City 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 December 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$98Average$376FlexibilityNo cancel feeOn-timeN/A
FrontierCheapest$115Average$220FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$247Average$420FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$256Average$461FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$268Average$445FlexibilityNo cancel feeOn-time71%

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