YOW - STL

C$ 255 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 7/6. 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$ 428
Typical prices: C$ 1,121-C$ 393
Air Canada
Sat 23/5Sun 24/5
YOW - STL • 1 stop
Cheapest one-way flights
C$ 255
Air Canada
Sun 7/6
YOW - STL • 1 stop
Top airlines
Cheapest • from C$ 428 (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$ 401 (round-trip)
Shortest trip • 4h 56m (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

Sat, 23 May - Sun, 24 May
Air Canada Logo
2:40 p.m. - 8:25 p.m.
YOW
-
STL
6h 45m
1 stop
Air Canada Logo
7:05 a.m. - 1:05 p.m.
STL
-
YOW
5h 00m
1 stop
C$ 428Air Canada
Thu, 28 May - Sat, 30 May
Air Canada Logo
7:00 a.m. - 12:06 p.m.
YOW
-
STL
6h 06m
1 stop
Air Canada Logo
7:05 a.m. - 1:05 p.m.
STL
-
YOW
5h 00m
1 stop
C$ 435Air Canada
Sat, 23 May - Wed, 27 May
United Airlines Logo
5:50 p.m. - 11:35 p.m.
YOW
-
STL
6h 45m
1 stop
United Airlines Logo
6:00 a.m. - 4:38 p.m.
STL
-
YOW
9h 38m
1 stop
C$ 436United Airlines
Tue, 2 Jun - Wed, 3 Jun
United Airlines Logo
10:44 a.m. - 9:16 p.m.
YOW
-
STL
11h 32m
1 stop
United Airlines Logo
6:00 a.m. - 4:38 p.m.
STL
-
YOW
9h 38m
1 stop
C$ 438United Airlines
Sat, 23 May - Wed, 27 May
Air Canada Logo
2:40 p.m. - 8:25 p.m.
YOW
-
STL
6h 45m
1 stop
Air Canada Logo
7:05 a.m. - 1:05 p.m.
STL
-
YOW
5h 00m
1 stop
C$ 444Air Canada
Fri, 12 Jun - Fri, 19 Jun
Air Canada Logo
7:00 a.m. - 12:06 p.m.
YOW
-
STL
6h 06m
1 stop
Air Canada Logo
2:15 p.m. - 9:15 p.m.
STL
-
YOW
6h 00m
1 stop
C$ 447Air Canada
Thu, 28 May - Sat, 30 May
United Airlines Logo
6:25 a.m. - 3:46 p.m.
YOW
-
STL
10h 21m
1 stop
United Airlines Logo
5:29 p.m. - 10:03 a.m.
STL
-
YOW
15h 34m
2 stops
C$ 496United Airlines
Mon, 8 Jun - Mon, 15 Jun
United Airlines Logo
5:50 p.m. - 11:35 p.m.
YOW
-
STL
6h 45m
1 stop
United Airlines Logo
5:41 p.m. - 10:03 a.m.
STL
-
YOW
15h 22m
2 stops
C$ 498United Airlines
Sat, 23 May - Wed, 27 May
United Airlines Logo
2:52 p.m. - 9:23 p.m.
YOW
-
STL
7h 31m
2 stops
United Airlines Logo
6:00 a.m. - 5:11 p.m.
STL
-
YOW
10h 11m
2 stops
C$ 521United Airlines
Sat, 23 May - Sun, 24 May
Air Canada Logo
2:40 p.m. - 9:23 p.m.
YOW
-
STL
7h 43m
2 stops
Air Canada Logo
7:05 a.m. - 1:05 p.m.
STL
-
YOW
5h 00m
1 stop
C$ 522Air Canada
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 May.

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$ 885 and C$ 874 respectively.

Good to know

Low seasonApril
Cheapest flightC$ 255
Best time to beat the crowds (25% less expensive on average)
Most popular time to fly and prices are also 13% 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 3 days, the lowest price for a flight from Ottawa to St. Louis was C$ 255 for a one-way ticket and C$ 428 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$ 691 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$ 862 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 9676 reviews
6.6Food
7.1Entertainment
7.3Comfort
7.7Boarding
8.1Crew
Airline reviews

Starlink is great Crew was polite Business class didn’t get a welcome drink just water and snacks were ok

8.0 ExcellentVolha, Apr 2026
YYZ - ORD
Read more United Airlines reviews

Starlink is great Crew was polite Business class didn’t get a welcome drink just water and snacks were ok

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

Good but airlines getting smaller. I didn't like the meal but the service was fine. Flight was fine and luggage arrived. So good.

They were fast and I like how they used to entertainment system to play video about the safety.

Hopped on time for the flight only to get deplaned and delayed another 2.5 hours.

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 ..

Flight itself was not bad at all. However: my checked bag (checked in Calgary) did not make it onto this flight as I found out after I landed at EWR. I still don't have it but it appears that it is on its way to me.

The crew was amazing! I was a bit surprised and disappointed that there was not wifi available for personal use. The only thing I would change would be the seat cushions. They are not comfortable at all for long flights.

Flight and attendance were very good we had 2 hour delay that took the shine of it

The seat design in the premium economy section leaves virtually no room under the seat to store a bag or purse. Other than that, it was a great flight. Arrived early.

The flight was delayed, but not for weather. We landed over 3hrs later than planned.

The stag were helpful, kind and liked the passengers. The plane was pristinely clean! Great flight!

My flight was delayed more than once, but Air Canada updated us regularly. Friends on other airlines had much worse experiences.

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

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

Information on your arrival and departure airports