YOW - STL

C$ 252 Find Cheap Flights from Ottawa 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 from Ottawa 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

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$ 399
United Airlines
Sat 11/4Mon 20/4
YOW - STL • 1 stop
Cheapest one-way flights
C$ 252
United Airlines
Tue 28/4
YOW - STL • 1 stop
Top airlines
Cheapest • from C$ 399 (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$ 403 (round-trip)
Shortest trip • 5h 00m (one-way)
Insights
Insights
Insights
Insights
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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

Sat, 11 Apr - Mon, 20 Apr
United Airlines Logo
6:00 a.m. - 10:31 a.m.
YOW
-
STL
5h 31m
1 stop
United Airlines Logo
7:45 a.m. - 5:07 p.m.
STL
-
YOW
8h 22m
1 stop
C$ 399United 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$ 405United 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$ 423United Airlines
Sat, 11 Apr - Sat, 18 Apr
United Airlines Logo
5:25 p.m. - 9:13 p.m.
YOW
-
STL
4h 48m
1 stop
United Airlines Logo
8:21 a.m. - 6:55 p.m.
STL
-
YOW
9h 34m
2 stops
C$ 424United Airlines
Tue, 14 Apr - Fri, 17 Apr
United Airlines Logo
10:44 a.m. - 9:13 p.m.
YOW
-
STL
11h 29m
1 stop
United Airlines Logo
7:45 a.m. - 1:59 p.m.
STL
-
YOW
5h 14m
1 stop
C$ 468United Airlines
Mon, 27 Apr - Mon, 4 May
United Airlines Logo
10:44 a.m. - 9:13 p.m.
YOW
-
STL
11h 29m
1 stop
United Airlines Logo
7:45 a.m. - 1:59 p.m.
STL
-
YOW
5h 14m
1 stop
C$ 472United Airlines
Wed, 3 Jun - Sat, 6 Jun
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$ 473United Airlines
Mon, 13 Apr - Thu, 16 Apr
United Airlines Logo
10:25 a.m. - 9:13 p.m.
YOW
-
STL
11h 48m
2 stops
United Airlines Logo
9:10 a.m. - 5:07 p.m.
STL
-
YOW
6h 57m
1 stop
C$ 479United Airlines
Sun, 12 Apr - Fri, 17 Apr
United Airlines Logo
6:25 a.m. - 10:45 a.m.
YOW
-
STL
5h 20m
1 stop
United Airlines Logo
10:00 a.m. - 9:16 p.m.
STL
-
YOW
10h 16m
2 stops
C$ 490United Airlines
Sun, 12 Apr - Mon, 20 Apr
United Airlines Logo
12:00 p.m. - 9:13 p.m.
YOW
-
STL
10h 13m
2 stops
United Airlines Logo
7:45 a.m. - 9:16 p.m.
STL
-
YOW
12h 31m
2 stops
C$ 502United 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.

Which airlines provide the cheapest flights from Ottawa to St. Louis?

The cheapest round-trip price for the route for each airline clicked by KAYAK users in the last 72 hours.

In the past 3 days, the cheapest round-trip tickets from Ottawa to St. Louis were found on United Airlines (C$ 399) and Lufthansa (C$ 521).

Good to know

Cheapest flightC$ 252
Most popular time to fly (11% 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$ 252 for a one-way ticket and C$ 399 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$ 755 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$ 865 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 9427 reviews
7.1Entertainment
7.3Comfort
7.7Boarding
8.1Crew
6.6Food
Airline reviews

Given I (and I’m assuming most people) have both carry in and a personal item included in their fare, I find it very unfair that on neither of my flights I was able to use the overhead for my small backpack because they were completely rammed with luggage, people personal items, jackets, hats and other items. So the only item I brought in had to be stuffed under my seat while they had their leg room and sat comfortable with all of their items in the overhead. This has to stop because I was uncomfortable on both flights when I only had one smaller item that could not be checked due to its contents (medication etc). Plenty of people could have checked theirs but chose not to and then took up the space allotment for 2 people.

8.0 ExcellentAnonymous, Feb 2026
YEG - IAH
Read more United Airlines reviews

Given I (and I’m assuming most people) have both carry in and a personal item included in their fare, I find it very unfair that on neither of my flights I was able to use the overhead for my small backpack because they were completely rammed with luggage, people personal items, jackets, hats and other items. So the only item I brought in had to be stuffed under my seat while they had their leg room and sat comfortable with all of their items in the overhead. This has to stop because I was uncomfortable on both flights when I only had one smaller item that could not be checked due to its contents (medication etc). Plenty of people could have checked theirs but chose not to and then took up the space allotment for 2 people.

Flight attendants had a little attitude. Food tastes no good.

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

From pre boarding to flight attendant, crew and baggage handler, excellent. Didn’t lost my luggage like West jet.

Very poor. The flight was delayed from Toronto because some forget to do there job . I got to my connecting gate in San Francisco 10 minutes before the departure.but this didn’t let me board even though the flight was still there for an other 30 minutes. The the gentleman at the unite airline desk told me that they usually wait for passengers but air Canada called and told them not to we I been rerouted to Manila instead of Hong Kong . In San Francisco they mad me check in my carryon bag . I was told the it will directly go yo ho chi minn cuyt but I was told that by the Vietnams airline desk that’s not there I’m 10 hours behind my scheduled flight and looks like I I’m going without baggage. I don’t have a chance of catching ..

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

Reliable, nice crew, I fly often on that flight and I like it all.

l really enjoy very much the flight was very pleasant

Essy to get on. The hostess gave very little pop, the plane was late getting in, and we are still waiting for our bags. This sucks. :/

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

Terrible…. Reported missing luggage’s with injectable meds that needed refrigeration. Yet, delivery could not be expedited. Luggage’s were delivered 5 days after arrival. The meds were useless as ice pack had melted. So disappointed!!!

It was a very small plane and was ok. No food or entertainment so there should be an option for NA.

My seat was covered in vomit and I will be reaching out to Air Canada

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.

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

Information on your arrival and departure airports