STL - YOW

$134 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 12/5. 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
$359
Multiple Airlines
Wed 12/17Fri 12/19
STL - YOW • 1 stop
Cheapest one-way
$134
Multiple Airlines
Fri 12/5
STL - YOW • 1 stop
Top airlines
Air Canada
Cheapest • from $361 (round-trip)
United Airlines
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+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 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

Wed, Dec 17 - Fri, Dec 19
Multiple Airlines Logo
11:50 am - 9:56 pmSTL-YOW
9h 06m1 stop
Multiple Airlines Logo
9:15 am - 3:29 pmYOW-STL
7h 14m1 stop
$359Multiple Airlines
Find Deal
Tue, Apr 7 - Wed, Apr 8
Air Canada Logo
4:05 pm - 11:04 pmSTL-YOW
5h 59m1 stop
Air Canada Logo
10:15 am - 3:24 pmYOW-STL
6h 09m1 stop
$361Air Canada
Find Deal
Sat, Dec 13 - Sat, Dec 20
United Airlines Logo
6:42 pm - 10:26 amSTL-YOW
14h 44m1 stop
United Airlines Logo
5:59 pm - 11:33 pmYOW-STL
6h 34m1 stop
$363United Airlines
Find Deal
Sat, Dec 13 - Sat, Dec 20
United Airlines Logo
6:42 pm - 1:36 pmSTL-YOW
17h 54m2 stops
United Airlines Logo
5:59 pm - 11:33 pmYOW-STL
6h 34m1 stop
$372United Airlines
Find Deal
Tue, Apr 7 - Wed, Apr 8
Air Canada Logo
8:00 am - 1:45 pmSTL-YOW
4h 45m1 stop
Air Canada Logo
5:45 am - 3:21 pmYOW-STL
10h 36m2 stops
$443Air Canada
Find Deal
Wed, Dec 17 - Fri, Dec 19
Multiple Airlines Logo
8:30 am - 5:18 pmSTL-YOW
7h 48m2 stops
Multiple Airlines Logo
10:20 am - 3:29 pmYOW-STL
6h 09m1 stop
$446Multiple Airlines
Find Deal
Tue, Apr 7 - Wed, Apr 8
Air Canada Logo
5:18 pm - 1:34 amSTL-YOW
7h 16m2 stops
Air Canada Logo
5:45 am - 3:21 pmYOW-STL
10h 36m2 stops
$455Air Canada
Find Deal
Thu, Feb 26 - Sun, Mar 1
United Airlines Logo
7:41 am - 5:18 pmSTL-YOW
8h 37m2 stops
United Airlines Logo
5:00 am - 12:25 pmYOW-STL
8h 25m2 stops
$461United Airlines
Find Deal
Sat, Nov 22 - Thu, Nov 27
American Airlines Logo
8:04 pm - 4:49 pmSTL-YOW
19h 45m2 stops
American Airlines Logo
6:45 am - 4:25 pmYOW-STL
10h 40m2 stops
$702American Airlines
Find Deal
Wed, Dec 17 - Fri, Dec 19
American Airlines Logo
9:53 am - 12:41 amSTL-YOW
13h 48m3 stops
American Airlines Logo
6:45 am - 1:25 amYOW-STL
19h 40m2 stops
$824American Airlines
Find Deal
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.

What’s the cheapest day of the week to fly from St. Louis to Ottawa?

The average price of all round-trip flights from St. Louis to Ottawa clicked on KAYAK for each day over the last 12 months.

For St. Louis to Ottawa, Saturday is the cheapest day to fly on average and Monday is the most expensive. Flying from Ottawa back to St. Louis, the best deals are generally found on Wednesday, with Monday being the most expensive.

Good to know

Low seasonFebruary
Cheapest flight$134
Best time to beat the crowds with an average 52% drop in price.
Most popular time to fly with an average 45% 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 $134 for a one-way ticket and $359 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 $822 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 $834 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 8999 reviews
7.7Boarding
8.1Crew
6.6Food
7.3Comfort
7.1Entertainment
Airline reviews

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.

10.0 ExcellentDr. Joseph, Oct 2025STL - ORD
Read more United Airlines reviews

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.

We had a layover from YVR to Denver. We bought 4 bottles of Absolut Vodka at the YVR Duty Free for $116.20, after going through security and American Customs Pre Clearance at YVR, Vancouver. When we landed in Denver, United put us behind the American Customs as well as TSA again for some reason. We were forced to go through American Customs and TSA again. TSA confiscated our rightfully owned Duty Free Absolut Vodka bottles. Because United incorrectly forced our flight behind American border and TSA again, we missed the connecting flight. After United put us on a later flight, we eventually arrived in Chicago very late, with hardly any sleep. I am looking for compensation from United for our incorrectly confiscated Absolut Vodka bottles worth $116.20, as well as compensation for incorrectly putting us behind American Customs and TSA again, causing us to miss our connecting flight, making us arrive extremely late in Chicago.

From the first moment you interact with United Airlines, you can expect nothing less but extreme frustration. The baggage handler at the bag drop seems completely unbothered by the presence of customers waiting in line. No help was extended to load the baggage whatsoever. And if any of your bags is overweight by 0.01 pound they will make you re-distribute everything in your suitcase just to play power trip. When it was time to board no help was extended to customers to locate their seats. Moreover. It was a chaotic mess at the gate when it was unclear who should board first and everyone just bunched up, trying to get on the plane. I am sure the crew was doing their best to perform their jobs while being paid their wages however it shouldn’t be that hard to smile once or twice when you’re in the business if serving customers. It is a shame for the United States of America to have a flagship carrier of such low caliber. Our flight was also delayed by about an hour and a half due to further delays prior to our inbound flight. Being someone who has travelled for both business and leisure in Asia, Europe, and South America I have never experienced such poor quality of service.

The pilots were late and it made us 1 hour late. The meat was tough and bok choy was also tough.

the delay for 3 hours was understandable due to weather conditions but the flight should’ve provided some on flight compensations or at least provide more food.

Our flight was understandably diverted to a small regional airport in Laramie, Wyoming due to weather conditions, which I fully recognize and appreciate. However, the low rating stems from the experience that followed: passengers remained on board for over an hour without the option to deplane and stretch, despite the aircraft being stationary. Although the pilot opened the cabin door, only he was permitted to exit. Meanwhile, passengers grew increasingly uncomfortable as warm summer air entered the cabin through the open door, and being in the second row meant we were impacted immediately. While the flight attendants made efforts to keep everyone at ease, I believe allowing passengers to deplane briefly, given the extended delay, would have significantly improved the overall experience.

Overall a very poor experience - booked premium economy tickets but due to last minute flight delays , all my itinery went for a toss and had to fly economy class with no access to lounge or any compensation by united airlines to make up for the flight delays . i had expected better experience than that from united.

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.

I liked a lot , the flight attendant so nice ,the seat very comfortable I enjoyed the flight , I will do it again with Air Canada,

Elderly female flight attendant was not customer friendly. There were only about 12 people on a regional jet that had about 60 seats. There were 8 exit row seats and none of them were taken. We attempted to sit in those seats and the flight attendant gave the standard " you didn't pay for those" so she would not allow us to move. What harm would that have caused ? They assigned seats to 5 of the 12 people in 2 rows, row 20 and 21. A simple friendly customer experience gesture of allowing us to sit in exit rows would have gone a long way in me having a very favorable impression on Air Canada. After that I have very poor impression of Air Canada and will not fly with them when I can avoid it.

Pearson Airport could not properly handle all the passengers who they needed to process in order to properly get them on board. As a result, I missed the departure of my flight from Toronto. The only saving grace is that Air Canada found a flight that only delayed me by one hour. However, this was no thanks to Pearson Airport!

Almost everything it was a “cool” ambiance but we arrived to Toronto so that it’s ok for me

The crew was really nice. The plane seats were kinda small even for a 5’6” / 158 lbs person.

Check in agent was very helpful and polite. He helped me board the earlier flight back home instead of waiting 2 hours at the airport for the next flight

extremely cramped seating... absolutely no leg room and when person in front of me reclined... I was pinned in my seat... absolutely ridiculous

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

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