Cheap flights from St. Louis to Ontario from $117
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Ontario departing on 8/9. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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United Airlines flights from St. Louis to Region of Ontario
Our best United Airlines deals on St. Louis to Region of Ontario flight tickets
Air Canada flights from St. Louis to Region of Ontario
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How to get the cheapest flight ticket from St. Louis to Region of Ontario
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
What is the cheapest month to fly to Region of Ontario?
The month of January is, on average, the cheapest month to fly to Region of Ontario from St. Louis, with most prices found around $312. If you aren’t able to travel during the month of January, then book flights to Region of Ontario from St. Louis during April instead. Flights to Region of Ontario in April, while not as cheap as those in January, still average around $314.
What is the cheapest day to depart on your flight to Region of Ontario?
According to our data, Thursday is the cheapest day to fly to Region of Ontario from St. Louis. The lowest ticket price found for a Thursday departure recently was $861. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. Flights from St. Louis to Region of Ontario on a Friday will generally be more expensive and average around $1,035. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.
What is the cheapest time of day to depart on your flight to Region of Ontario?
According to our data, the cheapest time of day to fly to Region of Ontario is in the afternoon. momondo users have found flights departing from St. Louis to Region of Ontario in the afternoon for as low as $936. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights at noon are often more expensive with an average ticket price of $1,176.
What is the cheapest Lambert-St Louis to Ontario flight route?
Fly from Lambert-St Louis to Toronto Pearson Intl for the best Lambert-St Louis - Ontario flight prices
How far in advance should I book a flight to Region of Ontario?
You are more likely to see cheaper flights to Region of Ontario from St. Louis when booking 23 weeks ahead of your departure date. In general, you can expect to find flights to Region of Ontario for around $462 when searching 23 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Region of Ontario from St. Louis for as low as $221 on momondo.
What cabin class options are available on Lambert-St Louis to Ontario flights?
There are 4 cabin classes available to choose from on Lambert-St Louis to Ontario flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Lambert-St Louis to Ontario?
American Airlines, Air Canada, and United Airlines are the most popular carriers operating from Lambert-St Louis to Ontario
What airlines fly to Region of Ontario?
Air Canada, United Airlines and American Airlines are the top three most popular airlines that fly to Region of Ontario from St. Louis according to our data. Air Canada is the first choice among our users, with 62% of people opting to fly with this airline when traveling to Region of Ontario. Keep in mind that there are 3 different airlines that fly to Region of Ontario on a routine basis, so you have a few additional options to choose from.
How many flights depart from St. Louis to Region of Ontario on average per day?
5 flights are operational daily from St. Louis to Region of Ontario as of June 2025. The most popular departure time for this route is 7:00AM, with 50% of flights per day taking off at noon.
How many flights depart from St. Louis to Region of Ontario on average per week?
As of June 2025, there are 37 flights per week flying from St. Louis to Region of Ontario. The most common day of the week flights depart is Mon, with 16% of flights taking off on this day.
Cheap St. Louis to Region of Ontario flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to Region of Ontario
Best Price Found | $117 |
|---|---|
Fastest flight time | 1h 55m |
Direct flights | Every day |
Airports in Region of Ontario | 3 airports |
When did momondo last update prices for flights from Lambert-St Louis Airport to Ontario?
Prices for flights from Lambert-St Louis Airport to Ontario were last updated today.
How many operators does momondo search for flights from Lambert-St Louis Airport to Ontario?
The number of operators available for flights from Lambert-St Louis Airport to Ontario is 4 as of June 2025.
How old do you have to be to fly from Lambert-St Louis Airport to Ontario?
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 Lambert-St Louis Airport to Ontario.
What documentation or ID do you need to fly to Ontario?
The required travel and health documents for your Ontario trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Ontario. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular plane model from St. Louis to Region of Ontario?
momondo data reveals that the most frequently booked plane model on the route from St. Louis to Region of Ontario is Canadair (Bombardier) Regional Jet 900, representing 51.85% of all bookings. The subsequent popular models are Airbus A220-300 at 34.44%, Boeing 777-300ER at 2.59%, and Boeing 777-200/200ER at 1.48%.
Best airlines flying from St. Louis to Region of Ontario
Compare and see reviews for airlines that fly from St. Louis to Region of Ontario with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $220 | Free Cancellation | Rating 7.4 8,801 reviews | |||
| PriceFrom $220 | Free Cancellation | Rating 7.1 9,554 reviews | |||
| PriceFrom $304 | Free Cancellation | Rating 7.2 10,000 reviews |
Why use momondo?
Why should I use momondo to find a flight deal from St. Louis to Ontario?
It is quick and easy to find St. Louis to Ontario flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to Ontario that suits you.
Can I find flights from St. Louis to Ontario with flexible booking policies on momondo?
Yes. All flights to Ontario from St. Louis on momondo can be compared and filtered by various policies on offer, including flexible booking.
How can momondo help me find flights from St. Louis to Ontario?
Once you have performed a search for St. Louis to Ontario flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.
I’m not ready to book a flight from St. Louis to Ontario right now. Can momondo alert me if prices change?
If you are simply researching potential flights to Ontario, momondo offers a useful price alert feature which will track prices for flights to Ontario from St. Louis and alert you when they change.