YOW - STL

C$ 376 Find Cheap Flights from Ottawa 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 from Ottawa to St. Louis departing on 2/11. 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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Everything you should know

Cheapest round-trip
C$ 643
Typical prices: C$ 574-C$ 887
Multiple Airlines
Fri 9/10Mon 12/10
YOW - STL • 1 stop
Cheapest one-way flights
C$ 376
Multiple Airlines
Mon 2/11
YOW - STL • 2 stops
Top airlines
Cheapest • from C$ 655 (round-trip)
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Direct flights
Not available
There are currently no direct flights between Ottawa and St. Louis. You’ll need at least 1 connection.
Insights
Insights
Insights
Insights
Top layover airports
Cheapest • Avg C$ 413 (round-trip)
Shortest trip • 4h 52m (one-way)
Insights
Insights
Insights
Insights
When to travel
Cheapest • 100% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Start a new search
KAYAK searches hundreds of sites at once to find you the best travel deals.
We hope you love your trip to St. Louis!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Ottawa to St. Louis (YOW-STL)

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

Fri, 9 Oct - Mon, 12 Oct
Multiple Airlines Logo
7:00 a.m. - 7:39 p.m.
YOW
-
STL
13h 39m
1 stop
Multiple Airlines Logo
10:35 a.m. - 11:48 p.m.
STL
-
YOW
12h 13m
2 stops
C$ 643Multiple Airlines
Sat, 19 Sep - Wed, 23 Sep
United Airlines Logo
6:00 a.m. - 3:38 p.m.
YOW
-
STL
10h 38m
3 stops
United Airlines Logo
12:59 p.m. - 9:35 p.m.
STL
-
YOW
7h 36m
1 stop
C$ 655United Airlines
Sat, 12 Sep - Sat, 19 Sep
United Airlines Logo
5:20 p.m. - 9:33 p.m.
YOW
-
STL
5h 13m
1 stop
United Airlines Logo
8:00 a.m. - 9:35 p.m.
STL
-
YOW
12h 35m
1 stop
C$ 655United Airlines
Sat, 12 Sep - Sat, 19 Sep
United Airlines Logo
6:25 a.m. - 12:03 p.m.
YOW
-
STL
6h 38m
1 stop
United Airlines Logo
8:00 a.m. - 6:59 p.m.
STL
-
YOW
9h 59m
2 stops
C$ 655United Airlines
Sat, 19 Sep - Wed, 23 Sep
Air Canada Logo
2:45 p.m. - 10:59 p.m.
YOW
-
STL
9h 14m
2 stops
Air Canada Logo
9:43 a.m. - 5:16 p.m.
STL
-
YOW
6h 33m
1 stop
C$ 751Air Canada
Sat, 19 Sep - Wed, 23 Sep
Air Canada Logo
3:10 p.m. - 10:59 p.m.
YOW
-
STL
8h 49m
2 stops
Air Canada Logo
10:53 a.m. - 5:16 p.m.
STL
-
YOW
5h 23m
1 stop
C$ 817Air Canada
Sat, 19 Sep - Wed, 23 Sep
Air Canada Logo
3:10 p.m. - 10:59 p.m.
YOW
-
STL
8h 49m
2 stops
Air Canada Logo
10:53 a.m. - 5:16 p.m.
STL
-
YOW
5h 23m
1 stop
C$ 818Air Canada
Sat, 12 Sep - Sat, 19 Sep
American Airlines Logo
7:00 a.m. - 9:44 p.m.
YOW
-
STL
15h 44m
3 stops
American Airlines Logo
5:18 p.m. - 2:55 p.m.
STL
-
YOW
20h 37m
2 stops
C$ 970American Airlines
Sat, 12 Sep - Sat, 19 Sep
American Airlines Logo
7:00 a.m. - 9:44 p.m.
YOW
-
STL
15h 44m
3 stops
American Airlines Logo
5:00 a.m. - 8:00 p.m.
STL
-
YOW
14h 00m
3 stops
C$ 1,115American Airlines
Tue, 1 Dec - Wed, 2 Dec
American Airlines Logo
7:00 a.m. - 12:03 a.m.
YOW
-
STL
18h 03m
2 stops
American Airlines Logo
9:53 a.m. - 12:43 a.m.
STL
-
YOW
13h 50m
3 stops
C$ 1,128American Airlines
Booking Insights

KAYAK's insights & trends for Ottawa to St. Louis flights

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

How much is a round-trip flight from Ottawa to St. Louis?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Ottawa to St. Louis departing in October.

Flight prices are typical for this route right now.

Flights to St. Louis from Ottawa usually cost between C$ 523 and C$ 1,303 in October.
The lowest price found in the past 5 days was C$ 643 on Multiple Airlines (9 Oct–12 Oct).

What is the cheapest month to fly from Ottawa to St. Louis?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ottawa to St. Louis, 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 Ottawa to St. Louis is February, where tickets cost C$ 0 (return) on average. On the other hand, the most expensive months are March and August, where the average cost of round-trip tickets is C$ 1,048 and C$ 982 respectively.

Good to know

Low season

May

Cheapest flight

C$ 376
Best time to beat the crowds (39% less expensive on average)
Most popular time to fly and prices are also 39% lower on average.
Flight from Ottawa to St. Louis

When to book flights from Ottawa to St. Louis

Are your dates flexible? Find out the best times to travel from Ottawa to St. Louis based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Ottawa to St. Louis

  • What is the cheapest flight from Ottawa to St. Louis?

    In the last 5 days, the lowest price for a flight from Ottawa to St. Louis was C$ 376 for a one-way ticket and C$ 643 for a round-trip.

  • Which airports will I be using when flying from Ottawa to St. Louis?

    Ottawa airport is called Ottawa and the only airport in St. Louis is Lambert-St Louis.

  • Which aircraft models fly most regularly from Ottawa to St. Louis?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Ottawa to St. Louis?

    Star Alliance is the only airline alliance operating flights between Ottawa and St. Louis.

  • Which is the best airline for flights from Ottawa to St. Louis, United Airlines or Air Canada?

    The two airlines most popular with KAYAK users for flights from Ottawa to St. Louis are United Airlines and Air Canada. With an average price for the route of C$ 696 and an overall rating of 7.4, United Airlines is the most popular choice. Air Canada is also a great choice for the route, with an average price of C$ 698 and an overall rating of 7.1.

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

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Louis from Ottawa 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 Ottawa 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 Ottawa with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ottawa 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 Ottawa up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airlines flying from Ottawa to St. Louis

 
See real verified KAYAK customer reviews for airlines flying from Ottawa to St. Louis. 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 Ottawa to St. Louis? 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.
7.4
United AirlinesOverall score based on 10055 reviews
7.7Boarding
6.7Food
7.1Entertainment
7.3Comfort
8.1Crew
Airline reviews

Flight was delayed “due to earlier delays of that plane”, so we were nearly three hours late.

8.0 ExcellentTodd, Jul 2026
DEN - STL
Read more United Airlines reviews

Flight was delayed “due to earlier delays of that plane”, so we were nearly three hours late.

Crew were welcoming, accommodating and they worked hard to find places for all carry on.

very average service no complimentary alcoholics drinks unlike other airlines such as Porter airlines No decent seats available during check-in time the day before

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

It was great. There were some issues prior to takeoff. The weather was poor so we had to go through deicing, and we were delayed a bit by the pilots' concern about one of the engines, but that's aviation. The pilots handled everything with aplomb, and kept us apprised

I dread trans-Pacific flights. They are very long. This was my first time on Universal, and it was my best crossing ever. The staff were professional, the hospitality was great, and the food was delicious. The entertainment system filled the long flight hours. I will seek out Universal flights from now onwards. 🙂

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

My flight was delayed about 1 1/2 hours in Chicago, but other then that it was a good flight.

The flight was delayed, it took longer than anticipated because of weather, and they broke my luggage.

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.

The flight was good. My luggage didn’t land with me when I arrived in Columbus. So grateful I was able to get my luggage back within the 2 hours😍👍.

It was out first time flying Air Canada and it was ok, comfort-wise. I hope airlines are able to get a quiet room installed for young children flying. Screaming and crying the whole time in business class is quite unfortunate. That was the only thing that really messed up the experience.

The Flight Attendant was particularly helpful to my wife, who was having a bad day.

Seriously need to improve the time schedule and the plans

It is air Canada so leaving 20 minutes late is very acceptable

One United employee a little impatient, also on flight WiFi was out for some time. I was happy to receive a complimentary alcoholic beverage for volunteering to check my carry on bag.

Everything was great, staff, planes, at the gate. All around everything was a pleasure flying .

I COULD NOT GET ON THE FLIGHT BECAUSE THE AIR CANADA CHECK-IN STAFF COULD NOT CHECK ME IN NEITHER COULD THEY DIRECT ME TO THE ALTERNATIVE CHECK-IN AIRLINE I DIDN'T FLY AND HAD TO REBOOK ANOTHER AIRLINE, PORTER FOR THE FOLLOWING DAY. I NEED MY REFUND FOR THE RETURN LEG

When a person pays 500 $ for one way ticket that person should have better seat not the seat before the bathrooms.🤔🤨

Seating is very tight. We were delayed 90 minutes to board, because the flight crew were late

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

Information on your arrival and departure airports