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Missouri

$107+ 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 9/2. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — STL
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
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 June 12, 2025.

Round-trip from

$234
(CheapOair)

One-way from

$107
(Trip.com)

Popular in

February

Cheapest in

August

Average price

$283
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. 8% potential increase in price ($27 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 June 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 June 12, 2025.

This CheapOair deal was found by Cheapflights users on 6/10. 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.
Tue 8/2612:59 amONT - STL
1 stop6h 12mFrontier
Sun 8/317:54 pmSTL - ONT
1 stop14h 51mFrontier
Deal found 6/10$234
This Frontier deal was found by Cheapflights users on 6/11. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/2712:59 amONT - MCI
1 stop10h 34mFrontier
Sun 8/312:18 pmMCI - ONT
1 stop11h 32mFrontier
Deal found 6/11$248
This Delta deal was found by Cheapflights users on 6/11. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/305:08 pmONT - STL
1 stop5h 35mDelta
Sat 7/56:00 amSTL - ONT
1 stop6h 38mDelta
Deal found 6/11$279
This Hawaiian Airlines deal was found by Cheapflights users on 6/11. 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 Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/227:10 amONT - MCI
1 stop6h 51mHawaiian Airlines
Sun 8/244:55 pmMCI - ONT
1 stop8h 58mHawaiian Airlines
Deal found 6/11$288
This Alaska Airlines deal was found by Cheapflights users on 6/11. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/67:10 amONT - MCI
1 stop7h 12mAlaska Airlines
Fri 10/175:57 pmMCI - ONT
1 stop7h 52mAlaska Airlines
Deal found 6/11$289
This American Airlines deal was found by Cheapflights users on 6/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/256:47 amONT - MCI
2 stops7h 13mAmerican Airlines
Tue 10/286:12 pmMCI - ONT
1 stop5h 48mAmerican Airlines
Deal found 6/11$294
This United Airlines deal was found by Cheapflights users on 6/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/121:19 pmONT - MCI
2 stops8h 12mUnited Airlines
Fri 8/156:00 amMCI - ONT
2 stops8h 14mUnited Airlines
Deal found 6/10$299
This American Airlines deal was found by Cheapflights users on 6/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/412:49 pmONT - SGF
1 stop5h 11mAmerican Airlines
Sat 7/126:32 pmSGF - ONT
1 stop6h 02mAmerican Airlines
Deal found 6/11$321
This Southwest deal was found by Cheapflights users on 6/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/187:00 amONT - MCI
1 stop5h 30mSouthwest
Sun 10/199:30 amMCI - ONT
1 stop5h 35mSouthwest
Deal found 6/10$328
This Delta deal was found by Cheapflights users on 6/11. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/41:15 pmONT - MCI
1 stop5h 52mDelta
Wed 7/95:45 amMCI - ONT
1 stop5h 02mDelta
Deal found 6/11$330
This Southwest deal was found by Cheapflights users on 6/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/305:25 pmONT - STL
1 stop5h 55mSouthwest
Mon 8/117:15 amSTL - ONT
2 stops7h 25mSouthwest
Deal found 6/9$333
This Alaska Airlines deal was found by Cheapflights users on 6/9. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/302:21 pmONT - STL
1 stop7h 38mAlaska Airlines
Wed 9/36:00 amSTL - ONT
1 stop10h 09mAlaska Airlines
Deal found 6/9$337

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 June 12, 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 8/26

12:59 am-9:11 am

1 stop6h 12m

Lambert-St Louis

Sun 8/31

7:54 pm-8:45 am

1 stop14h 51m

$234

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Wed 8/27

12:59 am-1:33 pm

1 stop10h 34m

Kansas City

Sun 8/31

2:18 pm-11:50 pm

1 stop11h 32m

$248

OntarioSt. Louis

ONT - STL

ONTSTL

Ontario

Mon 6/30

5:08 pm-12:43 am

1 stop5h 35m

Lambert-St Louis

Sat 7/5

6:00 am-10:38 am

1 stop6h 38m

$279

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Fri 8/8

12:00 pm-11:35 pm

1 stop9h 35m

Kansas City

Thu 8/14

6:45 am-1:26 pm

1 stop8h 41m

$288

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Mon 10/6

7:10 am-4:22 pm

1 stop7h 12m

Kansas City

Thu 10/16

7:00 am-12:37 pm

1 stop7h 37m

$289

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Sat 10/25

1:26 pm-10:24 pm

2 stops6h 58m

Kansas City

Tue 10/28

12:09 pm-5:45 pm

1 stop7h 36m

$294

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Tue 8/12

1:19 pm-11:31 pm

2 stops8h 12m

Kansas City

Fri 8/15

6:00 am-12:14 pm

2 stops8h 14m

$299

OntarioSpringfield

ONT - SGF

ONTSGF

Ontario

Fri 7/4

12:49 pm-8:00 pm

1 stop5h 11m

Springfield-Branson

Sat 7/12

6:32 pm-10:34 pm

1 stop6h 02m

$321

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Sat 10/18

7:00 am-2:30 pm

1 stop5h 30m

Kansas City

Sun 10/19

9:30 am-1:05 pm

1 stop5h 35m

$328

OntarioKansas City

ONT - MCI

ONTMCI

Ontario

Fri 7/4

1:15 pm-9:07 pm

1 stop5h 52m

Kansas City

Tue 7/8

5:45 am-8:47 am

1 stop5h 02m

$330

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/10

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 June 12, 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 June 12, 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
10,000 reviews

Food

7.1

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.8

Crew

8.5

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
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.8

Crew

8.5

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
4,287 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.8

Crew

8.5

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
7,950 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.8

Crew

8.5

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
2,494 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.8

Crew

8.5

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
8,790 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.8

Crew

8.5

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 $107. Users have also found prices from $140 and $144 on Delta and Hawaiian 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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$72Average$176FlexibilityNo cancel feeOn-time65%
FrontierCheapest$115Average$226FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$263Average$446FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$268Average$515FlexibilityNo cancel feeOn-time71%
DeltaCheapest$284Average$381FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$322Average$433FlexibilityNo cancel feeOn-time63%

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