$108 Find Cheap Flights from Ontario to Missouri - Compare and Save

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ontario to Missouri departing on 7/14. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Missouri

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Missouri, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Missouri, as well as popular online travel agencies
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Flight Deals

Cheap Flights from Ontario to Missouri

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
St. Louis
St. Louis1 stop$221
Kansas City
Kansas City1 stop$228
Springfield
Springfield1 stop$329
Columbia
Columbia2 stops$324
Joplin
Joplin2 stops$526
St. Louis
St. Louis1 stop$221
Kansas City
Kansas City1 stop$228
Springfield
Springfield1 stop$329
Columbia
Columbia2 stops$324
Joplin
Joplin2 stops$526

Book Cheap Ontario to Missouri Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to Missouri that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Ontario to Missouri

Sat, Aug 1 - Tue, Aug 4
Frontier Logo
6:00 am - 7:23 pm
ONT
-
STL
11h 23m
1 stop
Frontier Logo
8:08 pm - 11:50 pm
STL
-
ONT
29h 42m
1 stop
$221Frontier
Tue, Aug 11 - Sat, Aug 15
Frontier Logo
6:00 am - 1:00 pm
ONT
-
MCI
29h 00m
1 stop
Frontier Logo
1:45 pm - 11:50 pm
MCI
-
ONT
12h 05m
1 stop
$228Frontier
Wed, Jul 15 - Mon, Jul 20
Frontier Logo
6:00 am - 7:23 pm
ONT
-
STL
11h 23m
1 stop
Frontier Logo
7:10 pm - 8:03 am
STL
-
ONT
14h 53m
1 stop
$236Frontier
Wed, Jul 22 - Wed, Jul 29
Frontier Logo
3:40 pm - 3:47 pm
ONT
-
MCI
22h 07m
1 stop
Frontier Logo
1:45 pm - 11:50 pm
MCI
-
ONT
12h 05m
1 stop
$238Frontier
Tue, Jul 14 - Tue, Jul 28
American Airlines Logo
1:11 pm - 10:20 pm
ONT
-
COU
7h 09m
2 stops
American Airlines Logo
5:19 pm - 11:59 pm
COU
-
ONT
8h 40m
1 stop
$324American Airlines
Tue, Jul 14 - Tue, Jul 28
American Airlines Logo
1:11 pm - 10:20 pm
ONT
-
COU
7h 09m
2 stops
American Airlines Logo
11:45 am - 6:18 pm
COU
-
ONT
8h 33m
2 stops
$329American Airlines
Tue, Aug 4 - Fri, Aug 7
Multiple Airlines Logo
1:38 pm - 2:01 pm
ONT
-
SGF
22h 23m
1 stop
Multiple Airlines Logo
8:59 pm - 3:14 pm
SGF
-
ONT
20h 15m
2 stops
$339Multiple Airlines
Tue, Aug 4 - Fri, Aug 7
Multiple Airlines Logo
3:40 pm - 2:01 pm
ONT
-
SGF
20h 21m
1 stop
Multiple Airlines Logo
1:21 pm - 8:03 am
SGF
-
ONT
20h 42m
1 stop
$349Multiple Airlines
Tue, Sep 1 - Sat, Sep 5
United Airlines Logo
1:18 pm - 8:59 pm
ONT
-
COU
5h 41m
1 stop
United Airlines Logo
3:12 pm - 10:35 pm
COU
-
ONT
9h 23m
1 stop
$408United Airlines
Tue, Sep 1 - Sat, Sep 5
United Airlines Logo
1:18 pm - 8:59 pm
ONT
-
COU
5h 41m
1 stop
United Airlines Logo
10:55 am - 8:01 pm
COU
-
ONT
11h 06m
2 stops
$414United Airlines
Booking Insights

KAYAK's insights & trends for Ontario to Missouri flights

Get data-powered insights and trends into flights from Ontario to Missouri to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Ontario to Missouri?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Ontario to Missouri departing in August.

What is the cheapest month to fly from Ontario to Missouri?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ontario to Missouri, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Ontario to Missouri is September, when tickets cost $71 (return) on average. On the other hand, the most expensive months are March and December, when the average cost of round-trip tickets is $252 and $210 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Ontario to Missouri, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Ontario to Missouri, you should book around 3 weeks before departure, which saves you about 20% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 5 weeks before departure.

Good to know

Low seasonFebruary
Cheapest flight$108
Best time to beat the crowds with an average 15% drop in price.
Most popular time to fly with an average 23% increase in price.
Flight from Ontario to St. Louis

FAQs - booking Missouri flights

  • How does KAYAK find such low prices on flights from Ontario to Missouri?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to Missouri.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to Missouri?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Ontario to Missouri is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Ontario to Missouri?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly from Ontario to Missouri with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to Missouri?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from Ontario to Missouri up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 5 airlines serving from Ontario to Missouri

 
See real verified KAYAK customer reviews for airlines flying from Ontario to Missouri. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Ontario to Missouri? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.9
SouthwestOverall score based on 4246 reviews
7.5Entertainment
7.0Food
8.1Boarding
8.6Crew
8.0Comfort
Airline reviews

Flight was delayed, full flight and I had to change gates. Southwest flights are always late later in the day.

4.0 OkaySteven, Jun 2026
ONT - LAS
Read more Southwest reviews

Flight was delayed, full flight and I had to change gates. Southwest flights are always late later in the day.

Communication about the delayed flight was poor. We were told to move gates three times but that was bad information. We went from gate 128 to gate 126 and then to gate 123 and back to gate 126. Communication about the delay was bad. Ended up being 1 1/2 hour late getting home.

I have roller bag with food and medication told me I couldn't bring on my 2nd flight today. 15 years flying with SW never an issue with that bag.

I have not flown Southwest in awhile and had a very pleasant experience. From ticketing to boarding to the flight. The flight left on time and landed ahead of schedule. It won't be so long next time!!

Everything went smoothly and we even arrived a little bit early.

Boarded on time but once we were ready for take off, the crew determined that, although every seat was taken, somehow someone was on the wrong flight. Delay, delay delay, announcements and ended up with one person checking EVERY ID against their passenger Manifest only to figure out it was a "clerical error." We departed 54 minutes late causing me to run in the St. Louis Airport to make my connection and lose the priority boarding spot I had paid for. Unnecessary delay.

Flight was delayed due to plane not passing inspection And one of the crew had to time out and we had to wait for another one A 3 hour delay

Two hour delay including one of them on the tarmac second year in a row we’ve had a bad experience. Sad that Southwest is no longer a bargain and has failed to keep up the customer service they were once so famous for.

I liked receiving attention from aged and well experienced flight attendants. I disliked the non-gluten-free snack but I brought my own so I was OK.

They should not let people take up more than their seat space. Need to buy another ticket if they overflow into someone else’s space. Or you should make your seats larger to accommodate larger folks.

We departed early and made up time in the air allowing us to arrive 30 minutes early. Capt was incredibly genuine and thanked every passenger for flying with Delta. Completely humble and professional!

The boarding process needs to be refined. Sometimes the gate crew calls out the zones and then flip to showing the.zones boarding on the gate monitor display. So, unless you are huddled around the gate lanes watching the monitor, you could miss your boarding zone. Suggest the zones be announced each time a new zone is allowed to board.

This route with Delta always has delays or is cancelled. Aircrafts seem smaller and older. I fly Delta quite a bit - haven’t had issues with the international flights. But this route has always been the troublesome one

It was a great flight and the stewards and stewardess were all kind and accommodating!! The seats were comfortable and entertainment screen excellent!

737-800 in first class was pretty dumpy. Seat had an uncomfortable angle, storage under the seat was blocked so even my very modest backpack didn't fit, power outlet was flaky. Weird tiny seat pockets that couldn't hold a gallon ziploc bag, emesis bag missing, etc. etc. No in-flight service due to turbulence. Crew was excellent, boarding was smooth despite a full flight.

On 2 different flights the wifi was horrible and there was no drink or snack service.

Great, on time departure, friendly and accommodating crew, great leg room, Smith flight

The flight was overbooked and the staff at the gate started calling for volunteers to drop out and offering incentives. That delayed the flight

There was no wifi even after my husband paid for wifi it wasn’t working. The plane looked and felt old.

Update the cabin with tv screens or at least music sources.

Great staff. Clean plane, but we were delayed for more than an hour due to maintenance issues and had to board another plane.

Crew was amazing, takeoff wonderful. The bathroom was disgusting from before takeoff the odor made the flight uncomfortable as you could smell the bathroom from the center of the plane where we were sitting. Smelled like raw sewage. My daughter was throwing up as we landed due to the smell and horrible turbulence as we approached Newark.

Seat pitch is horrible especially on the 15 hour flight. Gate crew at SFO was Outstanding. The flight crew was also great.

Airport terminal was outdated, flight was on a small jet with no wifi

Essy to get on. The hostess gave very little pop, the plane was late getting in, and we are still waiting for our bags. This sucks. :/

Lately I like the planes have been exceptionally filthy. There’s lines of dust and dirt all across the ceiling in the vents, and the cracks in between the seats are literally full of food. It’s definitely not the quality of service that I was used to with United. I’m also very disappointed with the Wi-Fi! All I wanna do is knock out a few work jobs while I’m trapped in my seat And it spools so bad. They did provide me with a refund, but the process of getting that refund is so complicated. It’s unfortunate.

Excellent flight. Smooth, efficient boarding. Quick flight. Arrived early at STL.

Short flight - no food understandable. Flight was delayed for over an hour. Overall, it was good.

We boarded and buckled and then deplaned due to no pilot. Had to wait over 3 hours for a new pilot. Not weather related, just poor management.

Last minute gate change nearly caused us to miss our flight. Change was not announced or displayed in the main board at the old gate. Terrible communication. When we landed we had to wait 20 minutes because there was another plane at the assigned gate. Not the crew’s fault, but adding 20 minutes to a 45 minute flight sucked.

Ontario airport boarding was very easy to park and access, is clean and TSA took 10 minutes total. Check-in was a breeze and cruise was very nice.

Flight was 3 hours delayed. They gave our plan to two other routes. Need to knock that off.

Good flight, seated and had a water within 5 minutes. Crew was hospitable.

We called Kayak for a change due to the TSA situation in Atlanta. What we got was a canceled return flight (in error) and we had to find the mistake. Not happy with Kayak who blamed it on AA.

Small plane, poor meal choices for first class, bad terminal and boarding experience at LAX

Boarding delayed 20 minutes for no reason, no wifi, in flight entertainment, or snacks / waters?

The flight was on time and arrived early. The crew were friendly and helpful.

The chair cushions may need an upgrade. I have been noticing they are so worn out, thin so you’d sit in a dip 😄. Other than that, all was an enjoyable trip. Thanks AA!

VERY disappointed at the agent checking in my luggage. I know that the weight limit is 23 kg, a little over 50 pounds (50.71 pounds). Yet the agent kept repeating "50 pounds". So I said, the limit is 23 kg, and she had the audacity to say 'no, it is 22 kg!" Imagine my surprise. Was she ignorant or was she poorly trained? Not sure. The boarding process was pretty good. The speakers were loud enough so I still could hear them despite inconsiderate passengers continuing to speak while the announcements were going on. During the flight, the teenage girl sitting behind me kept pressing her feet to the back of my chair. I turned around several times, yet she did not get the hint. I did not make a fuss since I sense I had a bad streak that night with AA, so I just did the best I can to lean forward and not let that bother me.

It was wonderful upgrading to first. Plane was so cold thou. Crew was great. Wish there was a food option in first for such a long flight. Doesnt matter the time of day. Chintzy.

They didn’t offer a water, even after I asked

The takeoff was the smoothest I've ever experienced on any airline and this is the first time I've flown on frontier so this was an extremely pleasant surprise!

A lady asked to stop the flight after the tunnel pulled away and we began to depart a flight that was already hours late. The attendance respectfully stopped the the plane and had the tunnel return. After the tunnel returned the passenger claimed to have changed her mind . The tunnel was then put in reverse and the passenger remained on the plane .. They should have sent the sick passenger off the plane like initially replaced. They existed a couple off the plane prior to that situation.. So.. all and all.. it was a long and flight.. .

We understand and comply with Frontier’s bag sizes. We’ve had some problems in past while having to await other passengers who do not understand the baggage restrictions or have not prepaid and that is usually our biggest concern (others delaying us) with flying Frontier. Flying OUT of ONT, however, has always been a great experience. I’ve also noted even on delayed Frontier flights very knowledgeable pilots who manage expectations well.

Long lines, rude staff, everything that's offered you have to pay for.

The last time I flew Frontier was in the 1960s when it was a “real” airline. We flew this time because of the price & schedule. As the saying goes, you get what you pay for.

I appreciated the upgrade to free cary-on bag and seat selection at no charge

Flight was delayed on the runway for 40 minutes the crew did not even offer even water to passengers to compensate for the flight delayed. The flight was delayed due to aircraft mechanical issues. Worst customer service ever

This isna terribly run airlines. If you're one minute late, they will deny your ticket. Don't waste your time or money

Flight was delayed for more than 3 hours, crew at ONT airport was rude, and when we got to DFW the airplane had an issue landing, we had to be taxied to the terminal, and the luggage was hold until the next day.

Everything you need to know for your flight from Ontario to Missouri

Information on your arrival and departure airports