$149 Find Cheap Flights from Missouri to Ontario

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Low seasonJanuary
High seasonJuly
Cheapest flight$149
Best time to beat the crowds with an average 2% drop in price.
Most popular time to fly and prices are also 5% lower on average.
Flight from St. Louis to Toronto

FAQs for booking flights from Missouri to Ontario

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

    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 Missouri to Ontario.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Missouri to Ontario 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 Missouri to Ontario?

    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 Missouri to Ontario 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 Missouri to Ontario?

    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 Missouri to Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which is the cheapest airport to fly into in Ontario?

    Prices will differ depending on the departure airport, but generally, the cheapest airport to fly to in Ontario is Toronto Pearson Intl Airport (YYZ), with an average flight price of $404.

  • What is the cheapest day to fly to Ontario?

    Based on KAYAK data, the cheapest day to fly to Ontario is Thursday where round-trip tickets can be as cheap as $876. On the other hand, the most expensive day to fly is Friday, where round-trip prices are $1,049 on average.

  • What is the cheapest time of day to fly to Ontario?

    The cheapest time of day to fly to Ontario is generally in the evening, when round-trip flights cost $976 on average. Morning departures are around 5% more expensive than evening flights, on average. The most expensive time of day to fly to Ontario is generally in the afternoon, which is peak travel time and where the average cost of a ticket is $1,141.

  • What is the cheapest flight to Ontario?

    The cheapest ticket to Ontario from Missouri found in the last 72 hours was to Toronto Pearson Intl Airport, at $355 round-trip. The most popular route is Kansas City (MCI) to Toronto Pearson Intl Airport (YYZ) and the cheapest round-trip airline ticket found on this route in the last 72 hours was $355.

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

    The cheapest month for flights from Missouri to Ontario is September, when tickets cost $516 (return) on average. On the other hand, the most expensive months are November and April, when the average cost of round-trip tickets is $776 and $752 respectively.

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

    To get a below average price on the flight from Missouri to Ontario, you should book around 5 weeks before departure. For the absolute cheapest price, our data suggests you should book 23 weeks before departure.

  • How long is the flight to Ontario?

    An average nonstop flight from Missouri to Ontario takes 11h 50m, covering a distance of 939 miles. The shortest route is St. Louis (STL) to Toronto Pearson Intl Airport (YYZ) with an average flight time of 1h 55m.

  • What is the most popular destination in Ontario?

    Based on KAYAK flight searches, the most popular destination is Ottawa (100% of total searches to Ontario).

Top 5 airlines serving from Missouri to Ontario

Need help choosing which airline to fly with from Missouri to Ontario? 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.
8.0
DeltaOverall score based on 7944 reviews
7.9Comfort
8.5Crew
7.9Entertainment
8.2Boarding
7.3Food
Airline reviews

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.

6.0 GoodWalter, May 2025ONT - SLC
Read more Delta reviews

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.

Food from the flight from Atlanta to Santiago was very poor..

Flight was delayed due to weather. Crew did a nice job of making us comfortable. No complain complaints.

Our bag was lost so that made unnecessary chaos On our trip

Delta is my preferred airline. I've traveled with them for years. On time in most cases, good communication, easy to use app. Most planes are pretty nice. I was on a CRJ 700/900 however, which was pretty badly aged inside and needed a refresh. No infotainment, unreliable wifi, best to download before boarding or bring a book. Food choices are really just snacks on this flight, nice variety but about what you'd expect. Great staff and prompt in departure and early arrival too. Overall quite satisfied.

Crew was friendly Love the entertainment in the seat head rest.

Delta flight was on time, seats were comfortable, and crew was nice.

This had nothing to do with Delta… The flights were on time and flawless. The service was excellent. We purchased seats in (aisle/middle) comfort plus since this was a cross country flight. Unfortunately, the woman seated at the window was 300+ pounds and, as might be expected, covered up about a third of the middle seat also. there was absolutely nothing that Delta could have done about that… I just don’t know what the answer should be. If you purchase a seat, you should should be able to use the entire seat and not just the portion that someone else is not sitting/oozing in. Disappointing…there should be something that could be done….I'm just not sure what solution could be.

Delayed take-off. Very small plane so very scary with lots of bumps during the flight. Would never fly Delta on short flights in small 80 seaters plane again! Felt relieved when landed.

The worst part was I was NOT allowed in the lounge even though I was holding a first class ticket and have a premium American Express card. I have flown Business or First Class with many airlines. Delta is the ONLY one who does not extend this courtesy to anyone except people who hold the very expensive American Express card. As a result, I won’t fly Delta if I have any other choice.

The seat and leg room was not good. The food and beverage service was good.

Liked fold flat bed. Didn’t like having no window. Didn’t like poor choice of food and being served dinner very late, hours after take off of a 7:40pm flight. Servers not friendly. Food horrible in business class.

Everything is good except the dinner and breakfast. The sandwich is very delicious. Toilet is clean, I only use one of them. Flight attendants are very nice. 👍👍

A bit rush for transit. Food and entertainment are not available

Boarding was a little difficult. The gate area at O'Hare was very small and crowded due to multiple gates in the area. Could not hear the intercom, so had to rely on signage to see when my group was boarding and the signage was blocked by passengers standing in the gate. Flight was great and we arrived in Montreal on time.

My suitcase was completed destroyed. The top part is broken and unusable now.

When I booked it on Kayak it aaid that I wasn't allowed hamd luggage. I called United Airlines and it took them 6 minutes to figure out if I was allowed free hand luggage. Surely something that simple they should be able to tell me instantly.

I do prefer to fly United and have always had excellent service, except for bad weather. Flights are on time and staff is alway curtious and helpful

We were delayed in Toronto on the tarmac for THREE hours with no clear indication as to why except that it was not a safety hazard. Pilot did apologize more than once but even he was unable to explain why exactly we were delayed. I overheard the stewards saying that the captain was very frustrated with the situation as well because he was not able to explain why except it had something to do with water supply or system on the aircraft and now we needed to wait for an engineer to approve the aircraft for flight. It was very frustrating and distressing as a passenger and we should have been given complimentary meals at the very least.

All male crew was just too woke for me. I felt like a sardine. I will never take a window seat or the rearmost seat again. I booked early and did not pay for seat selection and that was a mistake. The security at IAH was atrocious. I was violated and radiated as I was in a hurry to connect to my other flight. I may have lost items under the seat in front of me that I couldn't see nor bend over to look.

The boarding was pretty easy. However, the first class seats are not lay flat as other airlines (like JetBlue) has and therefore sleeping was a challenge.

It was nobody’s fault - but the plane came 4-hrs late and we were updated randomly in 20-30 mins increments which left us hostage to sit and wait expectantly. It was very long and got very late. Our plane didn’t land until nearly 1 am! Also the toilet wasn’t working. The hosts were nice enough but were clearly “about to pass out” as one told me. Lastly, there was no snack or even time for it. Just a bad experience overall.

Was a normal flight but it was delayed, and there wasn't an explanation.

In flight connectivity (via T-Mobile) was often not working.

Pitch was very small. Knees were on the seat back in front of me.

really bad they refused to check in luggages that I had purchased, even showing them the transaction receipt from british airways app the staff in miami was MEDIOCRE

Several delays. Next flight was worse. Did not arrive home until 2am PT

Very helpful ground crew after an earlier flight delay and being rebooked on a different flight.

Everything about the flight was lovely…We left early, arrived early, cabin crew were efficient and helpful. Flight was easy and most pleasant.

First world problems, but still… We were seated in first class and asked for a cocktail on a very short, 50 minute flight. After our drink order was taken, a half hour went by, and we noticed that every other person in the small plane had been served except for us. We got up to ask about it, the drinks finally came, then were taken away three minutes later since the flight was so short. Really strange situation, on the other hand, we were in Utah.

It was good, flight was on time, boarding was smooth and done in zones, food was good too but there was no form of entertainment. Luggage’s were intact. So an overall good flight

The staff were the friendliest I have encountered in years. Absolutely great!

Plane changed to one with no entertainment system or ability to serve hot meals

Flight was delayed 3 times. Then cancelled due to pilot being timed out. They refused hotel vouchers. Gate attendants were very rude and could not help you at all.

No access to any entertainment No food other than a cookie or pretzels even tho flight was over the supper hour Seats very close together and very little leg room Staff was very good

Good. Would be better if the carry on baggage was free.

Horrible. I checked out myself that it seems that I can have a free carry-on. But they ask me to pay $75 when we are nearly boarding. It was tricky during check out that make you mistake that you can have a carry-on beside your personal item. Also they ask $75 in the airport instead of $35 during checkout. So the whole process is designed to make you this mistake

Westjet is one of the worst airlines in the world. 100% guaranteed to have flight delays and flight cancellations. Will never book again with Westjet.

Plane should have entertainment, instead of people paying to use wifi

Westjet has been absolutely terrible! Flights continually cancelled. Took 4 days to get home. Would have been 5, but we booked last flight with another airline after our Westjet flight was cancelled. Even pilot on original flight looked frustrated! Funny how they say cancelation is weather related, but they still have more than 1 other flight leaving to same destination on same day, but of course those are all full. This happened more than once on this trip. Two weather related cancelations and 1 mechanical. Not sure if the last flight even went ahead. Felt so sorry for families with kids and babies, and the older travellers. Felt like we lived out of suitcases and airports for days - SO RIDICULOUS! Next to no help from Westjet staff at airports, but it appears there is nothing they can help you with. Westjet has made it that they are unreachable when you need them! People were getting extremely frustrated, and rightfully so. Additional costs to us really added up, but Westjet literally DOESN'T CARE! Final straw was when we had to pay $1280 on a different airline (economy) trying to get home after another cancelled flight. Westjet will be refunding us a whole $140! Can't believe how this airline operates. We will never, ever use them again!

2.5 hour delay sitting in the plane on the tarmac, you tell me how the experience was

I hope these comments will find their way to AC customer experience team. Me and my spouse 50 years of aged coming back from 7 days perfect vacation... While boarding in FLL flight AC1621, one of the boarding agents (tall aged african american) man literelly yeld at my wife during the picture talking process. MAM ! STEP !! BACK !!! We are not illegal immegrants beying deported, nor are we in the millitary. We are customers returning home. This was unacceptable. While boarding in YYZ flight AC1154, one of the boarding agents (tall aged caucasian) man criticied with several complesant remarks my passport condition saying that I could not travel intl with it due to stain, decoloration, and BLOOD. My passport does not have blood on it! Yes it might be in less than perfect condition, but their are ways to talk to customer that does not imply not allow a boarding agent to be angry fathery like, or a custom agent looking at a suspicious individual. Both experience were less than acceptable for might I remind you a paying CUSTOMER returning home.

This flight didn't happen for me because of overbooking.

Terrible experience, flight was delayed both ways. Limited compensation for the 5+ hour delay. Will not be flying Air Canada Rouge, and don’t recommend you do either.

The boarding was relatively quick, the crew welcoming and flight uneventful. The omission of meals on all airlines is unacceptable especially when the flight is during a mealtime such as this one, (lunchtime), is unacceptable.

Everything was simple and easy. The lady at the gate was super friendly, I wish I had her name to share. She's a little older, dark-haired. You can tell she likes her job and would be a great influence on any young people training with her.

No Charging ports for personal electronics, which were required to use wifi entertainment.

Rushed, the boarding was a great deal like a Chinese fire drill.

it was red eye flight, it was ok, there was beverage service, thats it i didnt care much as i wanted to sleep

Everything went smoothly. I appreciate the selection of free movies.

Book cheap flights from Missouri to Ontario

Recent round-trip flight deals

5/29Thu
2 stops
12h 24mMCI-YYZ
6/4Wed
1 stop
11h 27mYYZ-MCI
$316
5/29Thu
1 stop
9h 37mMCI-YYZ
6/4Wed
1 stop
11h 27mYYZ-MCI
$319
5/25Sun
nonstopAir Canada
1h 55mSTL-YYZ
5/31Sat
1 stopAir Canada
6h 58mYYZ-STL
$409
6/13Fri
1 stopUnited Airlines
13h 57mSTL-YYZ
6/16Mon
nonstopUnited Airlines
2h 06mYYZ-STL
$414
6/6Fri
nonstopAir Canada
1h 55mSTL-YYZ
6/9Mon
1 stopAir Canada
5h 58mYYZ-STL
$417
6/12Thu
nonstopUnited Airlines
1h 55mSTL-YYZ
6/16Mon
1 stopUnited Airlines
4h 20mYYZ-STL
$419
6/11Wed
1 stopDelta
9h 14mSTL-YYZ
6/14Sat
1 stopDelta
9h 06mYYZ-STL
$427
6/13Fri
1 stopDelta
4h 45mSTL-YYZ
6/16Mon
1 stopDelta
9h 06mYYZ-STL
$429
6/30Mon
1 stopAmerican Airlines
9h 34mSTL-YYZ
7/2Wed
1 stopAmerican Airlines
10h 14mYYZ-STL
$467
5/31Sat
1 stopAmerican Airlines
15h 00mSGF-YYZ
6/3Tue
1 stopAmerican Airlines
9h 36mYYZ-SGF
$475

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Recent one-way flight deals

6/20Fri
1 stop
25h 37mSTL-YYZ
$149
5/24Sat
2 stops
26h 30mMCI-YUL
$165
6/20Fri
nonstopAir Canada
1h 55mSTL-YYZ
$177
6/6Fri
1 stopUnited Airlines
4h 19mSTL-YYZ
$183
6/19Thu
1 stopUnited Airlines
14h 44mSTL-YYZ
$187
9/4Thu
1 stopDelta
8h 30mSTL-YUL
$232
11/2Sun
nonstopAir Canada
1h 55mSTL-YYZ
$253
9/4Thu
2 stopsDelta
11h 30mSTL-YUL
$255
6/1Sun
1 stopAmerican Airlines
9h 44mMCI-YYZ
$263
8/8Fri
1 stopAmerican Airlines
15h 15mMCI-YUL
$311

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Last minute flights from Missouri to Ontario

Last minute flight, train and bus deals

5/7Wed
multi-stop
26h 32mSTL-YYZ
5/12Mon
multi-stop
9h 06mYYZ-STL
$501
5/7Wed
multi-stop
26h 32mSTL-YYZ
5/14Wed
multi-stop
15h 16mYYZ-STL
$508
5/7Wed
multi-stopAmerican Airlines
8h 27mSTL-YYZ
5/12Mon
multi-stopAmerican Airlines
8h 30mYYZ-STL
$763
5/9Fri
multi-stopAmerican Airlines
8h 27mSTL-YYZ
5/11Sun
multi-stopAmerican Airlines
8h 30mYYZ-STL
$848
5/7Wed
multi-stopUnited Airlines
6h 11mSTL-YYZ
5/12Mon
multi-stopUnited Airlines
23h 17mYYZ-STL
$921
5/7Wed
multi-stopUnited Airlines
8h 08mSTL-YYZ
5/12Mon
multi-stopUnited Airlines
19h 47mYYZ-STL
$931
5/7Wed
multi-stopDelta
10h 14mSTL-YYZ
5/14Wed
multi-stopDelta
11h 29mYYZ-STL
$952
5/9Fri
multi-stopDelta
7h 14mSTL-YYZ
5/11Sun
multi-stopDelta
8h 04mYYZ-STL
$959
5/7Wed
nonstopAir Canada
1h 55mSTL-YYZ
5/12Mon
nonstopAir Canada
2h 13mYYZ-STL
$1,530
5/9Fri
multi-stopAir Canada
7h 09mSTL-YYZ
5/11Sun
nonstopAir Canada
2h 13mYYZ-STL
$1,604

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Everything you need to know for your flight to Ontario

Cabin class types available on flights to Missouri

Cabin classes available on flights to Missouri. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.

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