STL - YOW

$340 Find Cheap Flights from St. Louis to Ottawa

This is the cheapest round-trip flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Ottawa departing on 10/30. 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

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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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

Thu, Oct 30 - Thu, Nov 6
Multiple Airlines Logo
10:57 am - 5:25 pmSTL-YOW
29h 28m1 stop
Multiple Airlines Logo
5:40 am - 1:57 pmYOW-STL
33h 17m2 stops
$340Multiple Airlines
Find Deal
Thu, Oct 30 - Thu, Nov 6
Multiple Airlines Logo
10:57 am - 5:25 pmSTL-YOW
29h 28m1 stop
Multiple Airlines Logo
9:30 am - 9:40 amYOW-STL
25h 10m1 stop
$437Multiple Airlines
Find Deal
Wed, Oct 29 - Wed, Nov 5
Multiple Airlines Logo
8:40 pm - 5:13 pmSTL-YOW
19h 33m2 stops
Multiple Airlines Logo
9:30 am - 1:17 pmYOW-STL
28h 47m1 stop
$439Multiple Airlines
Find Deal
Wed, Oct 29 - Wed, Nov 5
United Airlines Logo
1:35 pm - 10:26 amSTL-YOW
19h 51m2 stops
United Airlines Logo
5:15 am - 9:54 pmYOW-STL
17h 39m2 stops
$511United Airlines
Find Deal
Wed, Nov 26 - Sat, Nov 29
United Airlines Logo
1:35 pm - 10:26 amSTL-YOW
19h 51m2 stops
United Airlines Logo
12:05 pm - 11:44 pmYOW-STL
12h 39m2 stops
$649United Airlines
Find Deal
Wed, Nov 26 - Sat, Nov 29
United Airlines Logo
1:35 pm - 10:26 amSTL-YOW
19h 51m2 stops
United Airlines Logo
6:20 am - 3:46 pmYOW-STL
10h 26m1 stop
$699United Airlines
Find Deal
Thu, Oct 30 - Thu, Nov 6
United Airlines Logo
9:00 am - 9:18 pmSTL-YOW
11h 18m2 stops
United Airlines Logo
12:05 pm - 9:54 pmYOW-STL
10h 49m2 stops
$749United Airlines
Find Deal
Thu, Oct 30 - Thu, Nov 6
Multiple Airlines Logo
10:57 am - 12:42 amSTL-YOW
36h 45m3 stops
Multiple Airlines Logo
8:50 am - 12:20 pmYOW-STL
28h 30m3 stops
$763Multiple Airlines
Find Deal
Wed, Oct 29 - Wed, Nov 5
Air Canada Logo
4:05 pm - 11:08 pmSTL-YOW
6h 03m1 stop
Air Canada Logo
9:15 am - 3:29 pmYOW-STL
7h 14m1 stop
$770Air Canada
Find Deal
Thu, Oct 30 - Thu, Nov 6
Multiple Airlines Logo
10:57 am - 12:35 pmSTL-YOW
24h 38m2 stops
Multiple Airlines Logo
8:50 am - 12:20 pmYOW-STL
28h 30m3 stops
$772Multiple Airlines
Find Deal

Everything you should know

Top airlines
United Airlines
Cheapest • from $511 (round-trip)
United Airlines
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Cheapest round-trip
$340
Multiple Airlines
Thu 10/30Thu 11/6
STL - YOW • 1 stop
Cheapest one-way
Multiple Airlines
Tue 9/16
STL - YOW • multi-stop
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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

Cheapest flight$340
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 $340 for a round-trip ticket.

  • 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 8929 reviews
7.3Comfort
7.7Boarding
7.1Entertainment
6.6Food
8.1Crew
Airline reviews

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.

10.0 ExcellentAnonymous, Aug 2025EWR - YYZ
Read more United Airlines reviews

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.

Flight was actually on Air Canada. The flight itself was fine. Nothing special. Food was pretty pathetic except for cookies. They offered plenty of food and drinks but just wasn't very good. Even for airline food.

Boarding experience was smooth. Flight attendants were friendly and helpful. Entertainment system on the Houston-Edmonton flight did not function for passengers on the left side of the aisle. On the bird's eye flight from Quito to Houston, they should not serve a meal. No one needs to eat after midnight and it is disturbing for those passengers trying to sleep.

Flight was late as pilot crew had to land at different airport in their previous flight. Passengers boarded and had to wait for pilots inside plane. Series of incomplete and unnecessary announcements by an annoying voice, rather than complete, informative announcements.

Short flight. Everything was fine except the flight was delayed twice for a total of an hour.

I found the boarding easy and my seat was very comfortable as I had a lot of leg room. I am not too happy that I no longer have lounge access even though I used to get it with my TD credit card.

Flight cancelled. Major disruption to our travel. Do not use Air Canada from KC. To few flights.

There labor disputes cancelled my flight less than 24 hours before my boarding time but there customer service/website was easy enough to navigate and they rebooked me for no upcharge.

Re luggage I carried a backpack only. I did not check any bags in. However there were other passengers with carry on luggage going in the plane. My question is why are others allowed to have a carry on luggage inside the plane? Shouldn’t they have dropped it off at the gate? I’m asking because I could have brought the same thing instead of a backpack only. Please clarify for future reference. Thank you.

Like the service. Very hard to communicate or contact when have problems

Check in staff was incredibly rude and condescending. When I arrived at the gate I had been charged $125 for a checked back. I did have or check a bag. When I brought this to the attention of the staff member who checked me in, she said that she made a mistake and there was nothing she could do about it. I asked her to remove the charge and refund credit card, she said she could not and that I had to call my credit card company to contest the charge. I called Air Canada customer support, was put on hold, after 43 minutes a received a messages stating customer service was overwhelmed with calls and was then hung up on.

Refreshments and Air Hostess was good. Issues with customs in Toronto caused flight to depart and left me behind twice. Vouchers for delayed flight needs to increase.

Long wait to check in at the priority counter in Toronto

I had no communication, receipt etc from Air Canada until hours before flight

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

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