STL

C$ 252 Find Cheap Flights from Ontario to St. Louis

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 28/4. 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

Sat, 11 Apr - Tue, 14 Apr
United Airlines Logo
2:40 p.m. - 7:22 p.m.
YOW
-
STL
5h 42m
1 stop
United Airlines Logo
9:10 a.m. - 5:07 p.m.
STL
-
YOW
6h 57m
1 stop
C$ 398United Airlines
Sat, 11 Apr - Tue, 14 Apr
United Airlines Logo
5:25 p.m. - 9:13 p.m.
YOW
-
STL
4h 48m
1 stop
United Airlines Logo
6:30 a.m. - 4:38 p.m.
STL
-
YOW
9h 08m
2 stops
C$ 404United Airlines
Fri, 22 May - Sun, 24 May
United Airlines Logo
5:20 p.m. - 9:16 p.m.
YOW
-
STL
4h 56m
1 stop
United Airlines Logo
1:13 p.m. - 9:35 p.m.
STL
-
YOW
7h 22m
1 stop
C$ 422United Airlines
Mon, 13 Apr - Mon, 20 Apr
Multiple Airlines Logo
5:15 p.m. - 6:50 a.m.
YYZ
-
STL
38h 35m
2 stops
Multiple Airlines Logo
4:59 p.m. - 2:08 p.m.
STL
-
YYZ
20h 09m
1 stop
C$ 538Multiple Airlines
Tue, 28 Apr - Tue, 5 May
American Airlines Logo
12:30 p.m. - 11:46 p.m.
YUL
-
STL
12h 16m
1 stop
American Airlines Logo
4:30 p.m. - 11:44 a.m.
STL
-
YUL
18h 14m
1 stop
C$ 539American Airlines
Tue, 5 May - Sat, 9 May
American Airlines Logo
12:30 p.m. - 10:19 p.m.
YUL
-
STL
10h 49m
1 stop
American Airlines Logo
8:03 p.m. - 11:44 a.m.
STL
-
YUL
14h 41m
1 stop
C$ 545American Airlines
Mon, 13 Apr - Mon, 20 Apr
Multiple Airlines Logo
7:10 a.m. - 11:25 p.m.
YYZ
-
STL
17h 15m
1 stop
Multiple Airlines Logo
8:23 p.m. - 2:05 p.m.
STL
-
YYZ
16h 42m
2 stops
C$ 549Multiple Airlines
Sat, 2 May - Sun, 3 May
Air Canada Logo
6:30 p.m. - 8:25 p.m.
YUL
-
STL
2h 55mdirect
Air Canada Logo
1:00 p.m. - 4:35 p.m.
STL
-
YUL
2h 35mdirect
C$ 665Air Canada
Sun, 26 Apr - Sun, 3 May
Air Canada Logo
10:10 a.m. - 3:25 p.m.
YUL
-
STL
6h 15m
1 stop
Air Canada Logo
1:00 p.m. - 4:35 p.m.
STL
-
YUL
2h 35mdirect
C$ 683Air Canada
Wed, 15 Apr - Sat, 18 Apr
Delta Logo
9:30 a.m. - 7:26 p.m.
YUL
-
STL
10h 56m
1 stop
Delta Logo
5:59 p.m. - 11:08 p.m.
STL
-
YUL
4h 09m
1 stop
C$ 701Delta
Useful Info

Good to know

Low seasonJanuary
Cheapest flightC$ 252
Best time to beat the crowds but there is an average 8% increase in price.
Most popular time to fly and prices are also 17% lower on average.
Flight from Ottawa 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.

Travelling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Chesterfield
Collinsville
St. Charles
Fairview Heights
Eureka
Wentzville
Maryland Heights
Edwardsville
Farmington
Glencoe
O'Fallon
Clayton
Shrewsbury

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)