YOW - STL

C$ 401 Find Cheap Flights from Ottawa to St. Louis

This is the cheapest round-trip flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ottawa to St. Louis departing on 8/1. 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

KAYAK searches hundreds of travel sites at once for deals on flights to St. Louis

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ottawa to St. Louis, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ottawa to St. Louis, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
C$ 401
Overall average: C$ 772
Multiple Airlines
Thu 8/1Sun 11/1
YOW - STL • 1 stop
Cheapest one-way flights
C$ 419
Air Canada
Sun 21/12
YOW - STL • 1 stop
When to travel
November
Cheapest • 18% price drop
May
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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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

Thu, 8 Jan - Sun, 11 Jan
Multiple Airlines Logo
9:30 a.m. - 10:33 p.m.
YOW
-
STL
14h 03m1 stop
Multiple Airlines Logo
5:11 p.m. - 5:13 p.m.
STL
-
YOW
23h 02m1 stop
C$ 401Multiple Airlines
Thu, 8 Jan - Mon, 12 Jan
United Airlines Logo
5:11 p.m. - 10:58 p.m.
YOW
-
STL
6h 47m1 stop
United Airlines Logo
3:11 p.m. - 9:18 p.m.
STL
-
YOW
5h 07m1 stop
C$ 418United Airlines
Thu, 8 Jan - Mon, 12 Jan
United Airlines Logo
5:55 p.m. - 11:59 p.m.
YOW
-
STL
7h 04m1 stop
United Airlines Logo
7:00 a.m. - 1:32 p.m.
STL
-
YOW
5h 32m1 stop
C$ 419United Airlines
Thu, 8 Jan - Sun, 11 Jan
Multiple Airlines Logo
9:30 a.m. - 10:33 p.m.
YOW
-
STL
14h 03m1 stop
Multiple Airlines Logo
3:43 p.m. - 5:15 p.m.
STL
-
YOW
24h 32m2 stops
C$ 469Multiple Airlines
Thu, 8 Jan - Mon, 12 Jan
United Airlines Logo
10:30 a.m. - 10:58 p.m.
YOW
-
STL
13h 28m2 stops
United Airlines Logo
6:40 p.m. - 2:30 p.m.
STL
-
YOW
18h 50m2 stops
C$ 491United Airlines
Thu, 8 Jan - Mon, 12 Jan
United Airlines Logo
5:55 p.m. - 11:59 p.m.
YOW
-
STL
7h 04m1 stop
United Airlines Logo
6:40 p.m. - 2:30 p.m.
STL
-
YOW
18h 50m2 stops
C$ 492United Airlines
Thu, 8 Jan - Mon, 12 Jan
Air Canada Logo
9:15 a.m. - 3:29 p.m.
YOW
-
STL
7h 14m1 stop
Air Canada Logo
3:11 p.m. - 1:38 a.m.
STL
-
YOW
9h 27m2 stops
C$ 502Air Canada
Thu, 8 Jan - Sun, 11 Jan
United Airlines Logo
6:00 a.m. - 2:30 p.m.
YOW
-
STL
9h 30m2 stops
United Airlines Logo
6:40 p.m. - 1:32 p.m.
STL
-
YOW
17h 52m2 stops
C$ 585United Airlines
Thu, 8 Jan - Thu, 15 Jan
United Airlines Logo
5:55 p.m. - 11:59 p.m.
YOW
-
STL
7h 04m1 stop
United Airlines Logo
11:20 a.m. - 9:56 p.m.
STL
-
YOW
9h 36m2 stops
C$ 586United Airlines
Mon, 19 Jan - Sat, 24 Jan
American Airlines Logo
10:00 a.m. - 8:32 p.m.
YOW
-
STL
11h 32m2 stops
American Airlines Logo
6:43 p.m. - 4:53 p.m.
STL
-
YOW
21h 10m2 stops
C$ 655American 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.

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 November, where tickets cost C$ 684 (return) on average. On the other hand, the most expensive months are August and May, where the average cost of round-trip tickets is C$ 965 and C$ 941 respectively.

Good to know

Low seasonJune
Cheapest flightC$ 401
Best time to beat the crowds but there is an average 3% increase in price.
Most popular time to fly (12% more expensive 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 3 days, the lowest price for a flight from Ottawa to St. Louis was C$ 419 for a one-way ticket and C$ 401 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$ 843 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$ 841 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 9095 reviews
8.1Crew
6.6Food
7.1Entertainment
7.7Boarding
7.3Comfort
Airline reviews

The Sears in the 800s are not too good perfect Airbus why cant the new 737 fix that

8.0 ExcellentAnonymous, Dec 2025
YEG - IAH
Read more United Airlines reviews

The Sears in the 800s are not too good perfect Airbus why cant the new 737 fix that

Quick and seamless boarding. No entertainment but fast Starlink wifi for this short trip and the staff was really friendly.

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. 🙂

Lately I like the planes have been exceptionally filthy. There’s lines of dust and dirt all across the ceiling in the vents, and the cracks in between the seats are literally full of food. It’s definitely not the quality of service that I was used to with United. I’m also very disappointed with the Wi-Fi! All I wanna do is knock out a few work jobs while I’m trapped in my seat And it spools so bad. They did provide me with a refund, but the process of getting that refund is so complicated. It’s unfortunate.

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

The food quality sucks. One must starve if they do not eat flesh Or wheat based products Some variety would be expected. The trivial amount of snacks and or food is inhumane

We Left Calgary 1/2 hour late and that made for a tight connection in Denver. After arriving everything was done to help us make our connection. That was a great effort. Thank You United

Efficient all round, very good crew. Short flight so the food, of course, was just snacks

Overall, it was good. I was seating next to a wonderful lady and did not notice how time flew. Thanks

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

We were happy with the service and cost of checking a bag

It's kindof ridiculous that your system is even asking me about this since my flight was canceled and I wasn't rescheduled.

3 hr delay at the gate while they were doing maintenance. Next time, do not board passengers while maintenance is being performed

Digital check in is very poor with air canada compaired to other airlines

Baggage delayed we had to catch our cruise without any clothes 😒

Air Canada Rouge is great. Toronto Airport is the usual nightmare

Good but need to be better with the flight times.

The staff was great and made the long trip easy peasy!

The free Wi-fi for Aeroplan members was a great touch. The time passed quickly. I found the seats seemed a little closer together than I remember. Not Air Canada's fault, but we were about 20 minutes late landing because the airport was too busy. We had to circle around for a while. The boarding and disembarking went very smoothly.

Extremely turbulent landing. Crew was friendly and plane comfortable. Airport and US pre clearance was understaffed

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

Information on your arrival and departure airports