YOW - STL

$187 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 4/9. 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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41.299.237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest round-trip
$319
Overall average: $631
United Airlines
Tue 2/24Tue 3/3
YOW - STL • 1 stop
Cheapest one-way
$178
Air Canada
Thu 4/9
YOW - STL • 1 stop
Top airlines
United Airlines
Cheapest • from $319 (round-trip)
Air Canada
Best reviews • 7.1 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to travel
January
Cheapest • 31% 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 100s 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

Tue, Feb 24 - Tue, Mar 3
United Airlines Logo
5:11 pm - 9:05 pm
YOW
-
STL
4h 54m
1 stop
United Airlines Logo
6:25 am - 5:07 pm
STL
-
YOW
9h 42m
1 stop
$319United Airlines
Sat, May 16 - Mon, May 18
Air Canada Logo
7:00 am - 12:06 pm
YOW
-
STL
6h 06m
1 stop
Air Canada Logo
7:30 am - 1:10 pm
STL
-
YOW
4h 40m
1 stop
$343Air Canada
Sat, May 9 - Sat, May 16
Air Canada Logo
7:00 am - 12:06 pm
YOW
-
STL
6h 06m
1 stop
Air Canada Logo
7:30 am - 3:10 pm
STL
-
YOW
6h 40m
1 stop
$356Air Canada
Tue, Feb 24 - Tue, Mar 3
United Airlines Logo
2:05 pm - 9:05 pm
YOW
-
STL
8h 00m
2 stops
United Airlines Logo
6:25 am - 4:30 pm
STL
-
YOW
9h 05m
2 stops
$381United Airlines
Sat, May 9 - Sat, May 16
United Airlines Logo
6:25 am - 10:48 am
YOW
-
STL
5h 23m
1 stop
United Airlines Logo
7:45 am - 9:15 pm
STL
-
YOW
12h 30m
2 stops
$407United Airlines
Sat, May 9 - Sat, May 16
Delta Logo
5:55 am - 4:45 pm
YOW
-
STL
11h 50m
2 stops
Delta Logo
6:45 am - 5:35 pm
STL
-
YOW
9h 50m
2 stops
$426Delta
Fri, Mar 13 - Fri, Mar 20
United Airlines Logo
5:00 am - 4:23 pm
YOW
-
STL
12h 23m
2 stops
United Airlines Logo
5:00 am - 3:23 pm
STL
-
YOW
9h 23m
2 stops
$463United Airlines
Thu, Feb 26 - Thu, Mar 5
American Airlines Logo
6:40 am - 3:42 pm
YOW
-
STL
10h 02m
2 stops
American Airlines Logo
7:05 am - 6:23 pm
STL
-
YOW
10h 18m
2 stops
$465American Airlines
Sat, May 16 - Mon, May 18
American Airlines Logo
8:40 am - 7:26 pm
YOW
-
STL
11h 46m
2 stops
American Airlines Logo
6:00 am - 2:55 pm
STL
-
YOW
7h 55m
2 stops
$535American Airlines
Fri, Mar 13 - Fri, Mar 20
United Airlines Logo
6:00 am - 5:59 pm
YOW
-
STL
12h 59m
2 stops
United Airlines Logo
5:00 am - 10:26 am
STL
-
YOW
4h 26m
1 stop
$542United 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 January, where tickets cost $406 (return) on average. On the other hand, the most expensive months are August and May, where the average cost of round-trip tickets is $700 and $682 respectively.

Find deals

Good to know

Low seasonJune
Cheapest flight$178
Best time to beat the crowds but there is an average 6% increase in price.
Most popular time to fly with an average 15% increase in price.
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 $187 for a one-way ticket and $319 for a round-trip.

  • Do I need a passport to fly between Ottawa and St. Louis?

    Yes

  • 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.

  • 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. Booking your flights between Ottawa and STL can sometimes prove cheaper using this method.

  • 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 airline 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.
7.1
Air CanadaOverall score based on 10666 reviews
7.8Crew
6.8Entertainment
6.3Food
7.1Comfort
7.3Boarding
Airline reviews

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

10.0 ExcellentAngela, Jan 2026
YOW - YUL
Read more Air Canada reviews

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.

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

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

Information on your arrival and departure airports

Ottawa (YOW)
St. Louis (STL)