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Ontario

$87+ 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 5/10. Fares are subject to change and may not be available on all flights or dates of travel.
STL — ONT
May 6 — May 131
Tue 5/6
Tue 5/13
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 May 1, 2025.

Most accurate provider

Mytrip
3 stars

Most trusted provider

Mytrip
3 stars

Round-trip from

$188
(CheapOair)

One-way from

$87
(Cheapflightsfares)

Popular in

March

Cheapest in

September

Average price

$211
Provider with most accurate pricing for Kansas City-Los Angeles flight deals.
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Provider most trusted by Cheapflights users for Kansas City-Los Angeles flights.
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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. 22% potential increase in price ($80 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($11 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 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 May 1, 2025.

This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/49:55 pmSTL - ONT
1 stop11h 29mFrontier
Tue 5/612:59 amONT - STL
1 stop7h 00mFrontier
Deal found 4/30$178
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/88:51 pmMCI - ONT
1 stop16h 24mFrontier
Mon 5/1212:16 pmONT - MCI
1 stop5h 35mFrontier
Deal found 4/28$221
This American Airlines deal was found by Cheapflights users on 5/1. 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 8/158:23 amSGF - ONT
1 stop7h 18mAmerican Airlines
Fri 8/2211:59 pmONT - SGF
1 stop6h 45mAmerican Airlines
Deal found 5/1$269
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/17:00 amMCI - ONT
1 stop6h 59mAmerican Airlines
Thu 7/312:59 amONT - MCI
1 stop5h 52mAmerican Airlines
Deal found 4/30$299
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/235:23 pmSTL - ONT
1 stop7h 04mDelta
Tue 7/297:05 amONT - STL
1 stop7h 13mDelta
Deal found 4/30$307
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.
Sat 9/134:55 pmMCI - ONT
1 stop8h 58mAlaska Airlines
Wed 9/1711:39 amONT - MCI
1 stop7h 33mAlaska Airlines
Deal found 4/29$316
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/226:05 pmMCI - ONT
1 stop7h 37mDelta
Sun 5/256:00 amONT - MCI
1 stop5h 15mDelta
Deal found 4/30$317
This eDestinos 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/96:53 pmSTL - ONT
1 stop7h 06mMultiple Airlines
Sun 5/1112:16 pmONT - STL
3 stops29h 54mMultiple Airlines
Deal found 4/30$319
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 9/103:35 pmSTL - ONT
1 stop10h 24mHawaiian Airlines
Mon 9/1511:39 amONT - STL
1 stop10h 20mHawaiian Airlines
Deal found 4/29$324
This Orbitz 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/237:51 pmMCI - ONT
1 stop6h 00mMultiple Airlines
Sun 5/2511:51 amONT - MCI
1 stop9h 47mMultiple Airlines
Deal found 4/30$334
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/288:15 pmMCI - ONT
1 stop4h 55mSouthwest
Thu 7/35:25 pmONT - MCI
1 stop5h 00mSouthwest
Deal found 4/30$358
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/73:08 pmSTL - ONT
2 stops8h 30mAmerican Airlines
Wed 6/1112:55 pmONT - STL
2 stops8h 05mAmerican Airlines
Deal found 4/30$359

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 May 1, 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

Mon 5/12

9:55 pm-12:08 pm

1 stop16h 13m

Ontario

Sun 5/18

12:59 am-9:09 am

1 stop6h 10m

$188

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Mon 6/2

7:51 pm-10:43 am

1 stop16h 52m

Ontario

Thu 6/5

5:21 pm-7:06 pm

1 stop23h 45m

$248

SpringfieldOntario

SGF - ONT

SGFONT

Springfield-Branson

Fri 8/15

8:23 am-1:41 pm

1 stop7h 18m

Ontario

Fri 8/22

11:59 pm-8:44 am

1 stop6h 45m

$269

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Tue 7/1

7:00 am-11:59 am

1 stop6h 59m

Ontario

Thu 7/3

12:59 am-8:51 am

1 stop5h 52m

$299

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Wed 7/23

3:42 pm-10:27 pm

1 stop8h 45m

Ontario

Wed 7/30

10:05 pm-8:26 am

1 stop8h 21m

$307

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Thu 8/28

4:55 pm-11:53 pm

1 stop8h 58m

Ontario

Sun 8/31

7:10 am-4:01 pm

1 stop6h 51m

$316

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Tue 6/10

6:40 am-12:17 pm

1 stop7h 37m

Ontario

Sat 6/14

1:15 pm-9:07 pm

1 stop5h 52m

$317

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Wed 9/10

3:35 pm-11:59 pm

1 stop10h 24m

Ontario

Mon 9/15

11:39 am-11:59 pm

1 stop10h 20m

$324

Kansas CityOntario

MCI - ONT

MCIONT

Kansas City

Fri 5/23

7:51 pm-11:51 pm

1 stop6h 00m

Ontario

Sun 5/25

11:51 am-11:38 pm

1 stop9h 47m

$334

SpringfieldOntario

SGF - ONT

SGFONT

Springfield-Branson

Fri 7/4

5:45 am-12:14 pm

2 stops8h 29m

Ontario

Sat 7/12

1:34 pm-11:44 pm

1 stop8h 10m

$349

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/30

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 May 1, 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.

Rainfall in Ontario by month

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

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

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

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August 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 December, when temperatures are typically at their lowest (around 53.6 F).

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 May 1, 2025.
Read reviews from past customers who have flown Alaska Airlines, Southwest and Delta from Missouri to Ontario. 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
9,972 reviews

Boarding

8.1

Comfort

7.9

Food

7.1

Entertainment

7.1

Crew

8.5

Overall

8.0

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
9,972 reviews
Alaska Airlines
8.0
Very good
9,972 reviews

Boarding

8.1

Comfort

7.9

Food

7.1

Entertainment

7.1

Crew

8.5

Overall

8.0

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
9,972 reviews

Boarding

8.1

Comfort

7.9

Food

7.1

Entertainment

7.1

Crew

8.5

Overall

8.0

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
9,972 reviews

Boarding

8.1

Comfort

7.9

Food

7.1

Entertainment

7.1

Crew

8.5

Overall

8.0

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
2,408 reviews
Alaska Airlines
8.0
Very good
9,972 reviews

Boarding

8.1

Comfort

7.9

Food

7.1

Entertainment

7.1

Crew

8.5

Overall

8.0

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
9,972 reviews

Boarding

8.1

Comfort

7.9

Food

7.1

Entertainment

7.1

Crew

8.5

Overall

8.0

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 $87. Users have also found prices from $150 and $159 on Delta 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 6 airlines flying from Missouri to Ontario

Discover the top 6 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 May 1, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$98Average$180FlexibilityNo cancel feeOn-time65%
FrontierCheapest$114Average$208FlexibilityNo cancel feeOn-time62%
DeltaCheapest$181Average$361FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$268Average$408FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$294Average$426FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$326Average$411FlexibilityNo cancel feeOn-time63%

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