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Missouri

$88+ 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 5/29. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — STL
May 6 — May 131
Tue 5/6
Tue 5/13
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 May 1, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$176
(Cheapflightsfares)

One-way from

$88
(Cheapflightsfares)

Popular in

February

Cheapest in

May

Average price

$246
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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 May 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 May 1, 2025.

This Cheapflightsfares deal was found by Cheapflights users on 4/29. 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.
Sun 5/412:59 amONT - STL
1 stop6h 10mFrontier
Sat 5/108:15 pmSTL - ONT
1 stop5h 44mFrontier
Deal found 4/29$176
This CheapOair deal was found by Cheapflights users on 4/30. 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 5/2912:59 amONT - MCI
1 stop16h 05mFrontier
Fri 6/67:51 pmMCI - ONT
1 stop5h 59mFrontier
Deal found 4/30$228
This Expedia deal was found by Cheapflights users on 4/29. 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 5/2811:51 amONT - MCI
1 stop9h 47mMultiple Airlines
Fri 5/307:51 pmMCI - ONT
1 stop6h 00mMultiple Airlines
Deal found 4/29$263
This American Airlines deal was found by Cheapflights users on 4/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/42:44 pmONT - SGF
1 stop7h 10mAmerican Airlines
Tue 6/107:27 pmSGF - ONT
1 stop6h 32mAmerican Airlines
Deal found 4/28$269
This Hawaiian Airlines deal was found by Cheapflights users on 4/29. 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 Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/277:10 amONT - MCI
1 stop6h 51mHawaiian Airlines
Sun 8/314:55 pmMCI - ONT
1 stop8h 58mHawaiian Airlines
Deal found 4/29$298
This Delta deal was found by Cheapflights users on 4/29. 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.
Wed 5/2110:01 amONT - MCI
1 stop5h 08mDelta
Wed 5/286:05 pmMCI - ONT
1 stop7h 37mDelta
Deal found 4/29$299
This American Airlines deal was found by Cheapflights users on 4/29. 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.
Wed 5/216:01 amONT - MCI
1 stop6h 12mAmerican Airlines
Wed 5/2811:13 amMCI - ONT
2 stops9h 10mAmerican Airlines
Deal found 4/29$304
This Delta deal was found by Cheapflights users on 4/29. 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.
Sun 5/256:00 amONT - STL
1 stop5h 34mDelta
Tue 6/36:00 amSTL - ONT
1 stop7h 08mDelta
Deal found 4/29$307
This American Airlines deal was found by Cheapflights users on 4/29. 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 5/2511:59 pmONT - STL
1 stop7h 55mAmerican Airlines
Tue 6/35:00 amSTL - ONT
2 stops8h 50mAmerican Airlines
Deal found 4/29$312
This Alaska Airlines deal was found by Cheapflights users on 4/29. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/213:04 pmONT - MCI
1 stop6h 55mAlaska Airlines
Tue 8/264:55 pmMCI - ONT
1 stop8h 58mAlaska Airlines
Deal found 4/29$316
This Southwest deal was found by Cheapflights users on 4/29. 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.
Thu 5/295:45 amONT - MCI
1 stop4h 50mSouthwest
Sat 5/316:55 pmMCI - ONT
1 stop4h 50mSouthwest
Deal found 4/29$335
This Expedia deal was found by Cheapflights users on 4/28. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/1311:46 amONT - STL
1 stop10h 13mMultiple Airlines
Thu 5/159:55 pmSTL - ONT
1 stop11h 29mMultiple Airlines
Deal found 4/28$340

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 May 1, 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

Sun 5/4

12:59 am-9:09 am

1 stop6h 10m

Lambert-St Louis

Sat 5/10

8:15 pm-11:59 pm

1 stop5h 44m

$176

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Thu 5/29

12:59 am-7:04 pm

1 stop16h 05m

Kansas City

Fri 6/6

7:51 pm-11:50 pm

1 stop5h 59m

$228

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Wed 5/28

11:51 am-11:38 pm

1 stop9h 47m

Kansas City

Fri 5/30

7:51 pm-11:51 pm

1 stop6h 00m

$263

OntarioSpringfield

ONT - SGF

ONTSGF

Ontario

Wed 6/4

2:44 pm-11:54 pm

1 stop7h 10m

Springfield-Branson

Tue 6/10

7:27 pm-11:59 pm

1 stop6h 32m

$269

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Wed 8/27

7:10 am-4:01 pm

1 stop6h 51m

Kansas City

Sun 8/31

4:55 pm-11:53 pm

1 stop8h 58m

$298

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Wed 5/21

10:01 am-5:09 pm

1 stop5h 08m

Kansas City

Wed 5/28

6:05 pm-11:42 pm

1 stop7h 37m

$299

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Wed 5/21

6:01 am-2:13 pm

1 stop6h 12m

Kansas City

Wed 5/28

11:13 am-6:23 pm

2 stops9h 10m

$304

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Sun 5/25

6:00 am-1:34 pm

1 stop5h 34m

Lambert-St Louis

Tue 6/3

6:00 am-11:08 am

1 stop7h 08m

$307

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Sun 5/25

11:59 pm-9:54 am

1 stop7h 55m

Lambert-St Louis

Tue 6/3

5:00 am-11:50 am

2 stops8h 50m

$312

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Thu 8/21

3:04 pm-11:59 pm

1 stop6h 55m

Kansas City

Tue 8/26

4:55 pm-11:53 pm

1 stop8h 58m

$316

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/30

Showing 1-10 of 39 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 May 1, 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 May 1, 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
9,968 reviews

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.1

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
9,968 reviews
Alaska Airlines
8.0
Very good
9,968 reviews

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.1

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,294 reviews
Alaska Airlines
8.0
Very good
9,968 reviews

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.1

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,934 reviews
Alaska Airlines
8.0
Very good
9,968 reviews

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.1

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Hawaiian Airlines
7.9
Good
2,409 reviews
Alaska Airlines
8.0
Very good
9,968 reviews

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.1

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,696 reviews
Alaska Airlines
8.0
Very good
9,968 reviews

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.1

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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 $88. Users have also found prices from $149 and $150 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 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 May 1, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$72Average$176FlexibilityNo cancel feeOn-time65%
FrontierCheapest$116Average$226FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$266Average$452FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$268Average$569FlexibilityNo cancel feeOn-time71%
DeltaCheapest$284Average$383FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$317Average$416FlexibilityNo cancel feeOn-time63%

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