STL - YOW

$257 Find Cheap Flights from St. Louis to Ottawa

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Ottawa departing on 7/1. 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 Ottawa

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

Cheapest round-trip
$409
Air Canada
Mon 5/11Wed 5/13
STL - YOW • 1 stop
Cheapest one-way
$257
Delta
Wed 7/1
STL - YOW • 2 stops
Top airlines
Air Canada
Cheapest • from $409 (round-trip)
United Airlines
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
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We hope you love your trip to Ottawa!
Flight Deals
Booking Insights
Flight Deals

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

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

Mon, May 11 - Wed, May 13
Air Canada Logo
1:00 pm - 8:51 pm
STL
-
YOW
6h 51m
1 stop
Air Canada Logo
2:25 pm - 8:05 pm
YOW
-
STL
6h 40m
1 stop
$409Air Canada
Thu, May 28 - Sat, May 30
Air Canada Logo
1:00 pm - 8:51 pm
STL
-
YOW
6h 51m
1 stop
Air Canada Logo
2:25 pm - 8:05 pm
YOW
-
STL
6h 40m
1 stop
$410Air Canada
Sun, May 10 - Thu, May 14
Air Canada Logo
7:30 am - 3:10 pm
STL
-
YOW
6h 40m
1 stop
Air Canada Logo
7:00 am - 12:06 pm
YOW
-
STL
6h 06m
1 stop
$419Air Canada
Sat, Mar 14 - Thu, Mar 19
United Airlines Logo
7:00 pm - 10:26 am
STL
-
YOW
14h 26m
1 stop
United Airlines Logo
5:00 am - 2:42 pm
YOW
-
STL
10h 42m
2 stops
$494United Airlines
Mon, May 11 - Wed, May 13
United Airlines Logo
7:30 am - 3:10 pm
STL
-
YOW
6h 40m
1 stop
United Airlines Logo
10:00 am - 9:08 pm
YOW
-
STL
12h 08m
2 stops
$506United Airlines
Sat, Mar 14 - Thu, Mar 19
United Airlines Logo
7:41 am - 5:18 pm
STL
-
YOW
8h 37m
2 stops
United Airlines Logo
5:00 am - 2:42 pm
YOW
-
STL
10h 42m
2 stops
$507United Airlines
Thu, May 28 - Sat, May 30
Delta Logo
6:45 am - 5:35 pm
STL
-
YOW
9h 50m
2 stops
Delta Logo
5:55 am - 4:45 pm
YOW
-
STL
11h 50m
2 stops
$508Delta
Sat, Apr 25 - Mon, Apr 27
American Airlines Logo
6:00 am - 4:51 pm
STL
-
YOW
9h 51m
2 stops
American Airlines Logo
6:45 am - 11:48 pm
YOW
-
STL
18h 03m
2 stops
$509American Airlines
Sun, May 10 - Thu, May 14
United Airlines Logo
7:30 am - 1:10 pm
STL
-
YOW
4h 40m
1 stop
United Airlines Logo
12:00 pm - 9:08 pm
YOW
-
STL
10h 08m
2 stops
$534United Airlines
Sat, Mar 14 - Thu, Mar 19
United Airlines Logo
7:00 pm - 10:26 am
STL
-
YOW
14h 26m
1 stop
United Airlines Logo
5:11 pm - 9:07 pm
YOW
-
STL
4h 56m
1 stop
$555United Airlines
Booking Insights

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

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

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

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 St. Louis to Ottawa were found on Air Canada ($409) and United Airlines ($494).

Good to know

Low seasonFebruary
Cheapest flight$257
Best time to beat the crowds with an average 50% drop in price.
Most popular time to fly with an average 50% increase in price.
Flight from St. Louis to Ottawa

When to book flights from St. Louis to Ottawa

Are your dates flexible? Find out the best times to travel from St. Louis to Ottawa 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 St. Louis to Ottawa

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

    In the last 3 days, the lowest price for a flight from St. Louis to Ottawa was $257 for a one-way ticket and $409 for a round-trip.

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

    Yes, you'll most likely have to show a valid passport before boarding the plane in St. Louis and on arrival in Ottawa.

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

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

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

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

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

    The two airlines most popular with KAYAK users for flights from St. Louis to Ottawa are United Airlines and Air Canada. With an average price for the route of $824 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 $812 and an overall rating of 7.1.

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

    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 St. Louis to Ottawa.

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

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

    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 Ottawa with an airline and back to St. Louis with another airline. Booking your flights between St. Louis and YOW 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 St. Louis to Ottawa?

    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 Ottawa from St. Louis 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 St. Louis to Ottawa

 
See real verified KAYAK customer reviews for airlines flying from St. Louis to Ottawa. 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 St. Louis to Ottawa? 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 9210 reviews
7.1Entertainment
7.3Comfort
7.7Boarding
8.1Crew
6.6Food
Airline reviews

HORRIBLE, my initial flight was cancelled, they made me pay $200 extra dollars and that got cancelled as well! After 6 cancellations I decided to get a refund because I needed to get home to my babies. Out of $1000+ dollars they offered me only $40 in refund! Totally unacceptable! The flight that they cancelled I was able to fly it on another airline. I had to spend $400 on one way tickets just to get home! I’m still getting the runaround.

2.0 MediocreSonje’, Jan 2026
STL - EWR
Read more United Airlines reviews

HORRIBLE, my initial flight was cancelled, they made me pay $200 extra dollars and that got cancelled as well! After 6 cancellations I decided to get a refund because I needed to get home to my babies. Out of $1000+ dollars they offered me only $40 in refund! Totally unacceptable! The flight that they cancelled I was able to fly it on another airline. I had to spend $400 on one way tickets just to get home! I’m still getting the runaround.

Flight was delayed. De-icing took a while. When we landed had to wait for another plane to vacate our gate. Just an overall bad experience.

Not United Airlines' fault. It's ORL airport's fault.

United overall experience is great these days. Airport experience was very organized. Staff on flight were great. App and information as good as it gets.

Very nice flight love the small aircraft. We had a wonderful flight attendant. Nice to see someone that really enjoys her job. Don't have her name but had a southern accent.

Seats in waiting area and on plane hard as rock. Fast internet on the flight was great! Crew was kind.

Flight was delayed only slightly before takeoff due to traffic control. However, the flight arrived early to ORD. Good flight. United has been very reliable for me.

Not the fault of United—weather, reroute around weather, time sitting on tarmac, arrived couple hours late, too late for train into city necessitating a much pricier cab but weather…can’t be helped.

Flight was good but there are way to many announcements for credit cards etc.

I had no checked baggage but was required to hand over carry on baggage at the door of the plane. There was a lot of overboard space in the plane and I was one of the last ones. I ran to get my carry on but it was gone. I was given back at the plane door in Toronto, so the wait was not as long as it would have been at the carousel.

The plane was delayed substantially due to a mechanical problem, that being said, the airline was very fair with providing a meal coupon for us. I would rather arrive late on a mechanically sound plane than the alternative. The food served in the plane was just awful, however and I recommend a new catering company.

I travelled in Business class for the first time and wish I could do that again.

I waiting for 2 hrs to retrieve my luggage. Didn't get home till 3am.

The flight left late and I didn’t get a glass of bubbly upon boarding (which I’m used to when booking business class on other flights), but otherwise it was a pleasant flight with lovely, helpful crew members and I enjoyed my meal.

Flight was canceled for a reason they knew hours before but did not mention. Next the gate chnage from 37 to 38 at least 10 times. Ridiculous.

It was just fine. I managed to make all my connection too sbut had trouble in Munich with no wheel chair and trouble trying to get help from the airport people to get to the other terminal for my flight. Finally a wonderful lady Amelia, helped me to make my flight connection Timon with zero time to spare.

Super experience. Earlier than schedule departure and arrival. Baggage handling was very good

I would like to get my money back. I flight was 4 hours late on the way to detroit, And same on my way back to Brussels they cancelled my flight and give me an other ticket and i had to wait 5 hours.

All attendents were very efficient, pleasant and happy. Everything went smoothly. The seats could have been wider. There could have been more free food instead of just one small bar.

My seat was one of those that couldn't recline, but the problem was that it was abnormally upright, so the headrest actually made the seat concave, which was uncomfortable and hard on my lower back. I had to ball my jacket up and use it as lumbar support. goodness I had it with me.

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

Information on your arrival and departure airports