How many flights depart from Ontario to Missouri on average per week?

3 flights are operational weekly from Ontario to Missouri as of August 2026. The most popular departure day for this route is Sun, with 67% of flights per week taking off on this day.

What is the cheapest airline that flies from Ontario to Missouri?

Frontier, Alaska Airlines, and United Airlines are the most popular carriers operating from Ontario to Missouri

What airlines fly to Missouri?

Southwest, American Airlines and Delta are the top three most popular airlines that fly to Missouri from Ontario according to our data. Southwest is the first choice among our users, with 42% of people opting to fly with this airline when traveling to Missouri. Keep in mind that there are 7 different airlines that fly to Missouri on a routine basis, so you have a few additional options to choose from.

When did momondo last update prices for flights from Ontario Airport to Missouri?

Prices for flights from Ontario Airport to Missouri were last updated today.

How many operators does momondo search for flights from Ontario Airport to Missouri?

As of August 2026, there are 5 operators available to choose from for flights from Ontario Airport to Missouri.

How old do you have to be to fly from Ontario Airport to Missouri?

The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Ontario Airport to Missouri.

What documentation or ID do you need to fly to Missouri?

The travel and health documents required for your trip to Missouri can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Missouri. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

$66 Cheap Flights from Ontario to Missouri in 2026

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Find the cheapest flights from Ontario to Missouri

Round-trip

One-way

Last minute

Cheap round-trip flights

Enter your travel dates to find the best prices.

6:15 am - 7:17 pmONT Ontario-STL Lambert-St Louis

11h 02m1 stop Denver Intl

12:17 pm - 4:59 pmSTL Lambert-St Louis-ONT Ontario

6h 42m1 stop Las Vegas Harry Reid Intl

$178Frontier

Wed, Sep 9 - Wed, Sep 16

6:15 am - 7:17 pmONT Ontario-STL Lambert-St Louis

11h 02m1 stop Denver Intl

12:17 pm - 9:09 amSTL Lambert-St Louis-ONT Ontario

22h 52m1 stop Las Vegas Harry Reid Intl

$196Frontier

Fri, Sep 11 - Mon, Sep 14

5:45 am - 2:40 pmONT Ontario-STL Lambert-St Louis

6h 55m1 stop Las Vegas Harry Reid Intl

5:00 pm - 10:00 pmSTL Lambert-St Louis-ONT Ontario

7h 00m1 stop Houston Hobby

$268Southwest

Wed, Nov 11 - Wed, Nov 11

1:30 pm - 11:05 pmONT Ontario-STL Lambert-St Louis

7h 35m1 stop Las Vegas Harry Reid Intl

5:05 am - 9:45 amSTL Lambert-St Louis-ONT Ontario

6h 40m1 stop Las Vegas Harry Reid Intl

$268Southwest

Wed, Nov 11 - Tue, Dec 1

12:19 pm - 11:51 pmONT Ontario-MCI Kansas City

9h 32m1 stop Atlanta Hartsfield-Jackson

4:25 pm - 10:24 pmMCI Kansas City-ONT Ontario

7h 59m1 stop Atlanta Hartsfield-Jackson

$281Delta

Wed, Sep 23 - Mon, Sep 28

1:04 pm - 8:33 pmONT Ontario-MCI Kansas City

5h 29m1 stop Salt Lake City

4:25 pm - 10:24 pmMCI Kansas City-ONT Ontario

7h 59m1 stop Atlanta Hartsfield-Jackson

$281Delta

Sat, Sep 26 - Mon, Sep 28

10:25 am - 6:04 pmONT Ontario-STL Lambert-St Louis

5h 39m1 stop Dallas/Fort Worth

5:43 am - 12:03 pmSTL Lambert-St Louis-ONT Ontario

8h 20m2 stops Dallas/Fort Worth Phoenix Sky Harbor Intl

$282American Airlines

Wed, Sep 16 - Sat, Sep 26

1:05 pm - 12:27 amONT Ontario-STL Lambert-St Louis

9h 22m2 stops Phoenix Sky Harbor Intl Chicago O'Hare Intl

8:03 am - 12:14 pmSTL Lambert-St Louis-ONT Ontario

6h 11m1 stop Phoenix Sky Harbor Intl

$282American Airlines

Sat, Sep 26 - Wed, Oct 7

7:12 am - 5:10 pmONT Ontario-STL Lambert-St Louis

7h 58m1 stop Portland

8:10 pm - 11:47 pmSTL Lambert-St Louis-ONT Ontario

5h 37m1 stop Denver Intl

$293Multiple Airlines

Thu, Sep 24 - Sat, Sep 26

7:12 am - 5:10 pmONT Ontario-STL Lambert-St Louis

7h 58m1 stop Portland

8:10 pm - 11:47 pmSTL Lambert-St Louis-ONT Ontario

5h 37m1 stop Denver Intl

$298Multiple Airlines

Thu, Sep 24 - Wed, Sep 30

Cheap last minute flights

Enter your travel dates to find the best prices.

6:00 am - 7:23 pmONT Ontario-STL Lambert-St Louis

11h 23m1 stop Denver Intl

8:10 pm - 11:47 pmSTL Lambert-St Louis-ONT Ontario

5h 37m1 stop Denver Intl

$327Frontier

Sat, Aug 15 - Sat, Sep 19

6:00 am - 7:23 pmONT Ontario-STL Lambert-St Louis

11h 23m1 stop Denver Intl

8:10 pm - 11:47 pmSTL Lambert-St Louis-ONT Ontario

5h 37m1 stop Denver Intl

$366Frontier

Thu, Aug 13 - Mon, Sep 14

12:33 pm - 9:29 pmONT Ontario-SGF Springfield-Branson

6h 56m1 stop Dallas/Fort Worth

1:13 pm - 6:47 pmSGF Springfield-Branson-ONT Ontario

7h 34m1 stop Dallas/Fort Worth

$444American Airlines

Sat, Aug 15 - Mon, Aug 24

6:00 am - 3:23 pmONT Ontario-SGF Springfield-Branson

7h 23m1 stop Dallas/Fort Worth

6:00 am - 9:34 amSGF Springfield-Branson-ONT Ontario

5h 34m1 stop Dallas/Fort Worth

$444American Airlines

Sat, Aug 15 - Mon, Aug 24

6:00 am - 1:00 pmONT Ontario-MCI Kansas City

5h 00m1 stop Denver Intl

2:48 pm - 8:24 pmMCI Kansas City-ONT Ontario

7h 36m1 stop Portland

$463Multiple Airlines

Wed, Aug 12 - Wed, Aug 19

1:18 pm - 8:47 pmONT Ontario-SGF Springfield-Branson

5h 29m1 stop Denver Intl

4:58 pm - 9:59 pmSGF Springfield-Branson-ONT Ontario

7h 01m1 stop Houston George Bush Intcntl

$509United Airlines

Fri, Aug 14 - Mon, Aug 17

5:00 am - 6:02 pmONT Ontario-SGF Springfield-Branson

11h 02m2 stops Denver Intl Chicago O'Hare Intl

5:05 pm - 8:53 pmSGF Springfield-Branson-ONT Ontario

5h 48m1 stop Denver Intl

$512United Airlines

Wed, Aug 12 - Mon, Aug 17

10:49 am - 7:23 pmONT Ontario-STL Lambert-St Louis

6h 34m1 stop Denver Intl

6:00 am - 7:03 pmSTL Lambert-St Louis-ONT Ontario

15h 03m2 stops Los Angeles Seattle/Tacoma Intl

$527Multiple Airlines

Wed, Aug 12 - Wed, Aug 19

12:00 pm - 11:21 pmONT Ontario-STL Lambert-St Louis

9h 21m1 stop Atlanta Hartsfield-Jackson

6:00 am - 10:42 amSTL Lambert-St Louis-ONT Ontario

6h 42m1 stop Atlanta Hartsfield-Jackson

$556Delta

Tue, Aug 11 - Wed, Aug 12

6:00 am - 1:38 pmONT Ontario-STL Lambert-St Louis

5h 38m1 stop Salt Lake City

7:45 pm - 11:34 pmSTL Lambert-St Louis-ONT Ontario

5h 49m1 stop Salt Lake City

$594Delta

Wed, Aug 12 - Wed, Aug 12

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American Airlines flights from Ontario to Missouri

Our best American Airlines deals on Ontario to Missouri flight tickets

American Airlines

Sep 16

ONT10:25 amOntario

5h 39m

1 stop

STL6:04 pmLambert-St Louis

Sep 26

STL5:43 amLambert-St Louis

8h 20m

2 stops

ONT12:03 pmOntario

$282

American Airlines

Sep 24

ONT1:04 pmOntario

9h 23m

2 stops

STL12:27 amLambert-St Louis

Sep 26

STL5:43 amLambert-St Louis

8h 04m

1 stop

ONT11:47 amOntario

$299

American Airlines

Sep 4

ONT2:27 pmOntario

6h 01m

1 stop

COU10:28 pmColumbia Regional

Sep 10

COU6:26 pmColumbia Regional

7h 10m

1 stop

ONT11:36 pmOntario

$328

Frontier flights from Ontario to Missouri

Our best Frontier deals on Ontario to Missouri flight tickets

Frontier

Sep 11

ONT11:45 amOntario

5h 52m

1 stop

MCI7:37 pmKansas City

Sep 12

MCI8:32 pmKansas City

5h 15m

1 stop

ONT11:47 pmOntario

$214

Frontier

Sep 5

ONT7:56 pmOntario

14h 57m

1 stop

MCI12:53 pmKansas City

Sep 12

MCI8:32 pmKansas City

5h 15m

1 stop

ONT11:47 pmOntario

$218

Frontier

Sep 11

ONT6:15 amOntario

11h 02m

1 stop

STL7:17 pmLambert-St Louis

Sep 14

STL8:10 pmLambert-St Louis

5h 37m

1 stop

ONT11:47 pmOntario

$222

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OntarioSt. Louis

ONT Ontario - STL Lambert-St Louis

ONTSTL

Ontario

Wed 9/9

6:15 am-7:17 pm

1 stop11h 02m

Lambert-St Louis

Wed 9/16

12:17 pm-4:59 pm

1 stop6h 42m

$178

OntarioSt. Louis

ONT Ontario - STL Lambert-St Louis

ONTSTL

Ontario

Fri 9/11

6:15 am-7:17 pm

1 stop11h 02m

Lambert-St Louis

Mon 9/14

12:17 pm-9:09 am

1 stop22h 52m

$196

OntarioSt. Louis

ONT Ontario - STL Lambert-St Louis

ONTSTL

Ontario

Wed 11/11

5:45 am-2:40 pm

1 stop6h 55m

Lambert-St Louis

Wed 11/11

5:00 pm-10:00 pm

1 stop7h 00m

$268

OntarioSt. Louis

ONT Ontario - STL Lambert-St Louis

ONTSTL

Ontario

Wed 11/11

1:30 pm-11:05 pm

1 stop7h 35m

Lambert-St Louis

Tue 12/1

5:05 am-9:45 am

1 stop6h 40m

$268

OntarioKansas City

ONT Ontario - MCI Kansas City

ONTMCI

Ontario

Wed 9/23

12:19 pm-11:51 pm

1 stop9h 32m

Kansas City

Mon 9/28

4:25 pm-10:24 pm

1 stop7h 59m

$281

Quickest round-trip

OntarioKansas City

ONT Ontario - MCI Kansas City

ONTMCI

Ontario

Sat 9/26

1:04 pm-8:33 pm

1 stop5h 29m

Kansas City

Mon 9/28

4:25 pm-10:24 pm

1 stop7h 59m

$281

OntarioSt. Louis

ONT Ontario - STL Lambert-St Louis

ONTSTL

Ontario

Wed 9/16

10:25 am-6:04 pm

1 stop5h 39m

Lambert-St Louis

Sat 9/26

5:43 am-12:03 pm

2 stops8h 20m

$282

OntarioSt. Louis

ONT Ontario - STL Lambert-St Louis

ONTSTL

Ontario

Sat 9/26

1:05 pm-12:27 am

2 stops9h 22m

Lambert-St Louis

Wed 10/7

8:03 am-12:14 pm

1 stop6h 11m

$282

OntarioSt. Louis

ONT Ontario - STL Lambert-St Louis

ONTSTL

Ontario

Thu 9/24

7:12 am-5:10 pm

1 stop7h 58m

Lambert-St Louis

Sat 9/26

8:10 pm-11:47 pm

1 stop5h 37m

$293

OntarioSt. Louis

ONT Ontario - STL Lambert-St Louis

ONTSTL

Ontario

Thu 9/24

7:12 am-5:10 pm

1 stop7h 58m

Lambert-St Louis

Wed 9/30

8:10 pm-11:47 pm

1 stop5h 37m

$298

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Ontario to Missouri

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Other information

What is the cheapest month to fly to Missouri?

In general, January is the cheapest month to fly from Ontario to Missouri. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $329. If you aren’t able to travel to Missouri during the month of January, then flying in November is also cheap. Prices for this month can be found on momondo for an average of $335.

How far in advance should I book a flight from Ontario to Missouri?

You are more likely to see cheaper flights to Missouri from Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to Missouri for around $365 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Missouri from Ontario for as low as $318 on momondo.

Cheap Ontario to Missouri flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to Missouri

Fastest flight time	5h 16m
Direct flights	None

The fastest flight from Ontario to Missouri takes 5h 16m

There are no direct flights from Ontario to Missouri. There are no popular flight routes from Ontario to Missouri.

Search flight deals

Frequently asked questions about flying from Ontario to Missouri

When did momondo last update prices for flights from Ontario Airport to Missouri?
Prices for flights from Ontario Airport to Missouri were last updated today.
How many operators does momondo search for flights from Ontario Airport to Missouri?
As of August 2026, there are 5 operators available to choose from for flights from Ontario Airport to Missouri.
How old do you have to be to fly from Ontario Airport to Missouri?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Ontario Airport to Missouri.
What documentation or ID do you need to fly to Missouri?
The travel and health documents required for your trip to Missouri can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Missouri. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

Best airlines flying from Ontario to Missouri

Compare and see reviews for airlines that fly from Ontario to Missouri with momondo

Airline	Rating	Free Cancellation	Price
Delta	PriceFrom $98	Free Cancellation	Rating 7.8 8,497 reviews	Search Delta flights
Frontier	PriceFrom $105	Free Cancellation	Rating 5.6 2,713 reviews	Search Frontier flights
American Airlines	PriceFrom $259	Free Cancellation	Rating 7.1 11,897 reviews	Search American Airlines flights
Southwest	PriceFrom $266	Free Cancellation	Rating 8.0 4,218 reviews	Search Southwest flights
United Airlines	PriceFrom $289	Free Cancellation	Rating 7.4 10,095 reviews	Search United Airlines flights

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to Missouri?

Finding the right flight to Missouri from Ontario is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to Missouri quick and easy, saving you time and money.

Can I find flights from Ontario to Missouri with flexible booking policies on momondo?

momondo does allow users to show only those flights to Missouri from Ontario which offer a flexible booking policy as well as other useful filters and features.

How can momondo help me find flights from Ontario to Missouri?

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Ontario to Missouri.

I’m not ready to book a flight from Ontario to Missouri right now. Can momondo alert me if prices change?

Yes. momondo can track prices for Ontario to Missouri flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.