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Missouri

$85+ 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 5/9. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — STL
Apr 27 — May 41
Sun 4/27
Sun 5/4
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 April 22, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$181
(CheapOair)

One-way from

$85
(Trip.com)

Popular in

February

Cheapest in

May

Average price

$348
Provider with most accurate pricing for Los Angeles-Kansas City flight deals.
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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. 10% potential increase in price ($36 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 April 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 April 22, 2025.

This Frontier deal was found by Cheapflights users on 4/21. 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 4/2912:59 amONT - STL
1 stop7h 02mFrontier
Sat 5/38:15 pmSTL - ONT
1 stop5h 44mFrontier
Deal found 4/21$178
This CheapOair deal was found by Cheapflights users on 4/21. 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 5/812:59 amONT - MCI
1 stop16h 52mFrontier
Sun 5/118:51 pmMCI - ONT
1 stop16h 24mFrontier
Deal found 4/21$240
This Trip.com deal was found by Cheapflights users on 4/21. 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 5/910:52 amONT - STL
2 stops20h 23mMultiple Airlines
Mon 5/126:53 pmSTL - ONT
1 stop7h 06mMultiple Airlines
Deal found 4/21$262
This United Airlines deal was found by Cheapflights users on 4/21. 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.
Tue 5/65:05 amONT - SGF
1 stop5h 45mUnited Airlines
Wed 6/43:00 pmSGF - ONT
1 stop8h 10mUnited Airlines
Deal found 4/21$294
This American Airlines deal was found by Cheapflights users on 4/21. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/61:14 pmONT - SGF
2 stops8h 40mAmerican Airlines
Wed 6/47:17 pmSGF - ONT
1 stop6h 26mAmerican Airlines
Deal found 4/21$299
This Delta deal was found by Cheapflights users on 4/21. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/204:57 pmONT - MCI
1 stop5h 23mDelta
Wed 5/285:45 amMCI - ONT
1 stop5h 26mDelta
Deal found 4/21$299
This American Airlines deal was found by Cheapflights users on 4/21. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/252:44 pmONT - STL
1 stop6h 01mAmerican Airlines
Tue 6/32:19 pmSTL - ONT
1 stop6h 04mAmerican Airlines
Deal found 4/21$308
This American Airlines deal was found by Cheapflights users on 4/21. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/912:59 amONT - MCI
1 stop5h 52mAmerican Airlines
Sat 6/145:49 pmMCI - ONT
1 stop8h 10mAmerican Airlines
Deal found 4/21$318
This Delta deal was found by Cheapflights users on 4/22. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/246:00 amONT - STL
1 stop5h 34mDelta
Thu 7/241:30 pmSTL - ONT
1 stop7h 59mDelta
Deal found 4/22$325
This United Airlines deal was found by Cheapflights users on 4/21. 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.
Thu 6/51:33 pmONT - STL
1 stop5h 15mUnited Airlines
Sat 6/218:05 amSTL - ONT
2 stops11h 22mUnited Airlines
Deal found 4/21$348
This Southwest deal was found by Cheapflights users on 4/22. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/144:35 pmONT - STL
1 stop4h 50mSouthwest
Mon 8/46:45 pmSTL - ONT
1 stop7h 10mSouthwest
Deal found 4/22$366
This Southwest deal was found by Cheapflights users on 4/20. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/194:15 pmONT - MCI
1 stop4h 45mSouthwest
Sun 7/275:40 amMCI - ONT
1 stop5h 10mSouthwest
Deal found 4/20$366

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 April 22, 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

Tue 4/29

12:59 am-10:01 am

1 stop7h 02m

Lambert-St Louis

Sat 5/3

8:15 pm-11:59 pm

1 stop5h 44m

$178

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Thu 5/8

12:59 am-7:51 pm

1 stop16h 52m

Kansas City

Sun 5/11

8:51 pm-11:15 am

1 stop16h 24m

$240

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Fri 5/9

10:52 am-9:15 am

2 stops20h 23m

Lambert-St Louis

Mon 5/12

6:53 pm-11:59 pm

1 stop7h 06m

$262

OntarioSpringfield

ONT - SGF

ONTSGF

Ontario

Tue 5/6

5:05 am-12:50 pm

1 stop5h 45m

Springfield-Branson

Wed 6/4

3:00 pm-9:10 pm

1 stop8h 10m

$294

OntarioSpringfield

ONT - SGF

ONTSGF

Ontario

Tue 5/6

1:14 pm-11:54 pm

2 stops8h 40m

Springfield-Branson

Wed 6/4

7:17 pm-11:43 pm

1 stop6h 26m

$299

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Tue 5/20

4:57 pm-12:20 am

1 stop5h 23m

Kansas City

Wed 5/28

5:45 am-9:11 am

1 stop5h 26m

$299

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Sun 5/25

2:44 pm-10:45 pm

1 stop6h 01m

Lambert-St Louis

Tue 6/3

2:19 pm-6:23 pm

1 stop6h 04m

$308

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Mon 6/9

12:59 am-8:51 am

1 stop5h 52m

Kansas City

Sat 6/14

5:49 pm-11:59 pm

1 stop8h 10m

$318

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Sat 5/24

6:00 am-1:34 pm

1 stop5h 34m

Lambert-St Louis

Thu 7/24

1:30 pm-7:29 pm

1 stop7h 59m

$325

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Thu 6/5

6:00 am-4:53 pm

1 stop8h 53m

Lambert-St Louis

Wed 6/25

5:20 am-12:14 pm

2 stops8h 54m

$348

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/22

Showing 1-10 of 37 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 April 22, 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.

Rainfall in Missouri by month

Plan your trip to Missouri by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Missouri ranges from 1.1 - 5.2 inches per month. May is typically the wettest month, when rainfall can reach 5.2 in. January is typically the driest time to visit Missouri when rainfall is around 1.1 in.

Temperature in Missouri by month

Plan your trip to Missouri by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Missouri, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 28.4 F).

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 April 22, 2025.
Read reviews from past customers who have flown Alaska Airlines, Southwest and Delta from Ontario to Missouri. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,911 reviews

Comfort

7.9

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Alaska Airlines
8.0
Very good
9,911 reviews
Alaska Airlines
8.0
Very good
9,911 reviews

Comfort

7.9

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Southwest
8.0
Very good
4,287 reviews
Alaska Airlines
8.0
Very good
9,911 reviews

Comfort

7.9

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Delta
8.0
Very good
7,920 reviews
Alaska Airlines
8.0
Very good
9,911 reviews

Comfort

7.9

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Hawaiian Airlines
7.9
Good
2,392 reviews
Alaska Airlines
8.0
Very good
9,911 reviews

Comfort

7.9

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
United Airlines
7.4
Good
8,683 reviews
Alaska Airlines
8.0
Very good
9,911 reviews

Comfort

7.9

Overall

8.0

Food

7.1

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

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.

  • 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 $85. Users have also found prices from $106 and $149 on American Airlines and Alaska Airlines, 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 6 airlines flying from Ontario to Missouri

Discover the top 6 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 April 22, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$97Average$176FlexibilityNo cancel feeOn-time65%
FrontierCheapest$128Average$232FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$266Average$431FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$268Average$568FlexibilityNo cancel feeOn-time71%
DeltaCheapest$296Average$408FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$317Average$415FlexibilityNo cancel feeOn-time63%

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