$191 Find Cheap Flights from Ontario to St. Louis - 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 to St. Louis departing on 7/8. 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

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Flight Deals

Cheap Flights from Ontario to St. Louis

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to St. Louis 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 St. Louis

Wed, Sep 9 - Tue, Sep 22
American Airlines Logo
1:15 pm - 12:27 am
YYZ
-
STL
12h 12m
1 stop
American Airlines Logo
5:00 am - 2:32 pm
STL
-
YYZ
8h 32m
1 stop
$312American Airlines
Wed, Jul 15 - Wed, Jul 22
American Airlines Logo
7:17 am - 1:53 pm
YYZ
-
STL
7h 36m
1 stop
American Airlines Logo
6:55 am - 5:34 pm
STL
-
YYZ
9h 39m
1 stop
$324American Airlines
Wed, Jul 8 - Wed, Jul 15
American Airlines Logo
7:17 am - 1:53 pm
YYZ
-
STL
7h 36m
1 stop
American Airlines Logo
6:55 am - 5:34 pm
STL
-
YYZ
9h 39m
1 stop
$335American Airlines
Tue, Oct 27 - Wed, Oct 28
United Airlines Logo
11:00 am - 3:38 pm
YOW
-
STL
5h 38m
1 stop
United Airlines Logo
9:23 am - 5:14 pm
STL
-
YOW
6h 51m
1 stop
$375United Airlines
Tue, Aug 18 - Sat, Nov 7
Air Canada Logo
2:35 pm - 6:42 pm
YOW
-
STL
5h 07m
1 stop
Air Canada Logo
4:15 pm - 11:48 pm
STL
-
YOW
6h 33m
1 stop
$382Air Canada
Tue, Aug 18 - Sat, Nov 7
United Airlines Logo
6:05 am - 3:38 pm
YOW
-
STL
10h 33m
2 stops
United Airlines Logo
9:23 am - 9:34 pm
STL
-
YOW
11h 11m
1 stop
$383United Airlines
Tue, Jul 28 - Tue, Aug 4
Air Canada Logo
9:00 am - 2:02 pm
YOW
-
STL
6h 02m
1 stop
Air Canada Logo
12:10 pm - 7:45 pm
STL
-
YOW
6h 35m
1 stop
$389Air Canada
Wed, Jul 22 - Mon, Jul 27
Multiple Airlines Logo
2:50 pm - 6:15 pm
YYZ
-
STL
28h 25m
2 stops
Multiple Airlines Logo
7:10 pm - 5:09 pm
STL
-
YYZ
20h 59m
1 stop
$418Multiple Airlines
Mon, Aug 3 - Mon, Aug 10
Multiple Airlines Logo
10:50 am - 6:05 pm
YYZ
-
STL
32h 15m
2 stops
Multiple Airlines Logo
7:10 pm - 5:09 pm
STL
-
YYZ
20h 59m
1 stop
$419Multiple Airlines
Wed, Nov 4 - Sat, Nov 7
Delta Logo
9:28 am - 8:51 pm
YUL
-
STL
12h 23m
1 stop
Delta Logo
6:00 am - 1:36 pm
STL
-
YUL
6h 36m
1 stop
$489Delta
Useful Info

Good to know

Low seasonJanuary
Cheapest flight$191
Best time to beat the crowds with an average 20% drop in price.
Most popular time to fly and prices are also 17% lower on average.
Flight from Toronto to St. Louis

FAQs for booking flights from Ontario to St. Louis

  • How does KAYAK find such low prices on flights from Ontario to St. Louis?

    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 St. Louis.

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

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

    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 to St. Louis with an airline and back to Ontario with another airline.

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

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

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
O'Fallon
Wentzville
Farmington
Eureka
Litchfield
Grafton
Shrewsbury
Glencoe

Everything you need to know for your flight to St. Louis

Information on the airport you'll fly into in St. Louis

St. Louis (STL)