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$99+ Cheap flights from Missouri to Ontario (ONT)

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 8/13. Fares are subject to change and may not be available on all flights or dates of travel.
STL — ONT
Aug 5 — Aug 121
Tue 8/5
Tue 8/12
1 adult, Economy
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Cheap flight deals from Missouri to Ontario

Keep the following information in mind while searching for Missouri to Ontario flight deals. Data was last updated July 31, 2025.

Round-trip from

$215
(Cheapflightsfares)

One-way from

$99
(Frontier)

Popular in

March

Cheapest in

September

Average price

$260
From Missouri to Ontario
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One-way flight from Missouri to Ontario
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Highest demand for flights based on searches. 25% potential increase in price ($91 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($12 potential savings vs. average RT price).
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Average for round-trip flights in July 2025
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Find flight deals from Missouri to Ontario

Cheapest flights from Missouri to Ontario
Explore the most affordable flight options available from Missouri to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 31, 2025.

This Cheapflightsfares deal was found by Cheapflights users on 7/29. 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.
Tue 11/47:52 pmSTL - ONT
1 stop5h 58mFrontier
Fri 11/712:59 amONT - STL
1 stop6h 08mFrontier
Deal found 7/29$205
This FlightHub deal was found by Cheapflights users on 7/30. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/88:01 pmMCI - ONT
1 stop5h 49mFrontier
Tue 8/1212:59 amONT - MCI
1 stop15h 24mFrontier
Deal found 7/30$215
This American Airlines deal was found by Cheapflights users on 7/29. 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.
Tue 8/268:23 amSGF - ONT
1 stop7h 16mAmerican Airlines
Tue 9/211:59 pmONT - SGF
1 stop7h 40mAmerican Airlines
Deal found 7/29$268
This American Airlines deal was found by Cheapflights users on 7/29. 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.
Sat 8/307:53 amSTL - ONT
1 stop5h 39mAmerican Airlines
Sat 9/612:47 pmONT - STL
1 stop5h 28mAmerican Airlines
Deal found 7/29$277
This Delta deal was found by Cheapflights users on 7/30. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/215:11 pmSTL - ONT
1 stop7h 09mDelta
Tue 8/2611:45 amONT - STL
1 stop8h 17mDelta
Deal found 7/30$286
This Southwest deal was found by Cheapflights users on 7/30. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/215:45 amSTL - ONT
1 stop6h 00mSouthwest
Tue 8/2612:35 pmONT - STL
2 stops7h 15mSouthwest
Deal found 7/30$291
This Southwest deal was found by Cheapflights users on 7/30. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/66:00 amMCI - ONT
1 stop6h 35mSouthwest
Tue 9/912:35 pmONT - MCI
1 stop5h 15mSouthwest
Deal found 7/30$292
This Delta deal was found by Cheapflights users on 7/30. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/215:45 amMCI - ONT
1 stop5h 10mDelta
Thu 8/286:05 amONT - MCI
1 stop5h 13mDelta
Deal found 7/30$295
This Alaska Airlines deal was found by Cheapflights users on 7/30. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/224:55 pmMCI - ONT
1 stop8h 58mAlaska Airlines
Mon 8/253:04 pmONT - MCI
1 stop6h 55mAlaska Airlines
Deal found 7/30$296
This United Airlines deal was found by Cheapflights users on 7/30. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/276:00 amMCI - ONT
2 stops8h 13mUnited Airlines
Wed 9/37:00 amONT - MCI
1 stop6h 56mUnited Airlines
Deal found 7/30$302
This American Airlines deal was found by Cheapflights users on 7/30. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/275:45 amMCI - ONT
2 stops7h 47mAmerican Airlines
Wed 9/31:10 pmONT - MCI
2 stops7h 57mAmerican Airlines
Deal found 7/30$307
This Delta deal was found by Cheapflights users on 7/31. 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 8/153:54 pmSGF - ONT
1 stop8h 26mDelta
Tue 8/197:05 amONT - SGF
1 stop8h 48mDelta
Deal found 7/31$319

Cheapflights Fare Finder

 
Customize your flight search to find flights from Missouri to Ontario 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 July 31, 2025.
Use the filters below to find and compare flights from Missouri to Ontario that are best for you.

Fly from

Missouri

Fly to

Ontario

Route

Depart

Return

Price

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Wed 10/8

7:52 pm-11:50 pm

1 stop5h 58m

Ontario

Tue 10/21

12:59 am-9:07 am

1 stop6h 08m

$206

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Mon 8/4

8:01 pm-11:50 pm

1 stop5h 49m

Ontario

Tue 8/5

12:59 am-6:23 pm

1 stop15h 24m

$215

SpringfieldOntario

SGF - ONT

SGFONT

Springfield-Branson

Tue 8/26

8:23 am-1:39 pm

1 stop7h 16m

Ontario

Tue 9/2

11:59 pm-9:39 am

1 stop7h 40m

$268

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Sat 8/30

7:53 am-11:32 am

1 stop5h 39m

Ontario

Sat 9/6

12:47 pm-8:15 pm

1 stop5h 28m

$277

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Thu 8/21

6:00 am-10:35 am

1 stop6h 35m

Ontario

Tue 8/26

7:05 am-7:07 pm

1 stop10h 02m

$286

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Thu 8/21

5:45 am-9:45 am

1 stop6h 00m

Ontario

Tue 8/26

12:35 pm-9:50 pm

2 stops7h 15m

$291

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Sat 9/6

6:00 am-10:35 am

1 stop6h 35m

Ontario

Tue 9/9

12:35 pm-7:50 pm

1 stop5h 15m

$292

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Thu 8/21

5:45 am-8:55 am

1 stop5h 10m

Ontario

Thu 8/28

6:05 am-1:18 pm

1 stop5h 13m

$295

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Fri 8/22

4:55 pm-11:53 pm

1 stop8h 58m

Ontario

Tue 8/26

7:10 am-4:01 pm

1 stop6h 51m

$296

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Wed 8/27

6:00 am-12:13 pm

2 stops8h 13m

Ontario

Wed 9/3

7:00 am-3:56 pm

1 stop6h 56m

$302

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/31

Showing 1-10 of 38 results
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Best time to book a flight from Missouri to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Missouri 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 Missouri to Ontario

What is the cheapest month to book a flight from Missouri to Ontario?

Currently, August is the cheapest month in which you can book a flight from Missouri to Ontario (average of $246). Flying from Missouri to Ontario in March is currently the most expensive (average of $328). 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 MO to ONT?

Find hourly flight availability from Missouri to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 31, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Missouri to Ontario as you normally would.

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated July 31, 2025.
Read reviews from past customers who have flown Alaska Airlines, Southwest, and Delta from Missouri to Ontario. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

Crew

8.5

Comfort

7.8

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

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

Crew

8.5

Comfort

7.8

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
4,246 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

Crew

8.5

Comfort

7.8

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
7,981 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Hawaiian Airlines
7.8
Good
2,611 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

Crew

8.5

Comfort

7.8

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
8,900 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

Crew

8.5

Comfort

7.8

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 Missouri to Ontario. 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 into for flights to Ontario from Missouri?

    For a flight from Missouri to Ontario, you will be flying into Ontario. Ontario (ONT) is just 3.1 mi from the center of the city.

  • What are the cheapest airlines to fly from Missouri to Ontario one-way?

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $99. Users have also found prices from $136 and $145 on Alaska Airlines and American Airlines, respectively.

  • What are the most popular routes from Missouri to Ontario?

    When deciding which route to take from Missouri to Ontario consider Kansas City - Ontario, Lambert-St Louis - Ontario or Springfield-Branson - Ontario as they are the most popular.

  • Can I find deals for flights from Missouri to Ontario that include hotel bookings?

    Yes. In addition to deals on Missouri to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Missouri to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Missouri to Ontario.

  • Can I find deals for business class flights from Missouri to Ontario?

    Yes. Cheapflights offers flight deals from Missouri to Ontario 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 Missouri to Ontario?

    Currently, August is the cheapest month in which you can book a flight from Missouri to Ontario (average of $246). Flying from Missouri to Ontario in March is currently the most expensive (average of $328). 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 Missouri to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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Top 5 airlines flying from Missouri to Ontario

Discover the top 5 airlines that operate flights from Missouri to Ontario. 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 July 31, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$107Average$227FlexibilityNo cancel feeOn-time62%
DeltaCheapest$181Average$346FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$268Average$385FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$294Average$429FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$316Average$410FlexibilityNo cancel feeOn-time63%

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