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$372+ Cheap flights from St. Louis (STL) to Ottawa (YOW)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/10. Fares are subject to change and may not be available on all flights or dates of travel.
STL — YOW
Dec 13 — Dec 201
Sat 12/13
Sat 12/20
1 adult, Economy
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Cheap flight deals from St. Louis to Ottawa

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Ottawa (YOW). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated November 13, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$361
(Air Canada)
Provider with most accurate pricing for Lambert-St Louis-Ottawa flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Ottawa flights.
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From Lambert-St Louis to Ottawa
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Find flight deals from St. Louis to Ottawa

Cheapest flights from St. Louis to Ottawa
Explore the most affordable flight options available from St. Louis to Ottawa. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 13, 2025.

This United Airlines deal was found by Cheapflights users on 11/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/101:00 pmSTL - YOW
1 stop7h 18mUnited Airlines
Wed 12/176:00 amYOW - STL
2 stops10h 40mUnited Airlines
Deal found 11/12$372
This Kiwi.com deal was found by Cheapflights users on 11/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/224:13 pmSTL - YOW
2 stops31h 29mMultiple Airlines
Thu 11/279:30 amYOW - STL
1 stop15h 27mMultiple Airlines
Deal found 11/12$451
This Kiwi.com deal was found by Cheapflights users on 11/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/224:13 pmSTL - YOW
2 stops31h 29mMultiple Airlines
Tue 11/259:30 amYOW - STL
1 stop15h 27mMultiple Airlines
Deal found 11/12$461
This Kiwi.com deal was found by Cheapflights users on 11/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/224:13 pmSTL - YOW
2 stops31h 29mMultiple Airlines
Fri 11/284:20 pmYOW - STL
1 stop8h 37mMultiple Airlines
Deal found 11/12$493
This Kiwi.com deal was found by Cheapflights users on 11/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/224:13 pmSTL - YOW
2 stops31h 29mMultiple Airlines
Wed 11/269:30 amYOW - STL
1 stop15h 27mMultiple Airlines
Deal found 11/12$508
This Kiwi.com deal was found by Cheapflights users on 11/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/224:13 pmSTL - YOW
2 stops31h 29mMultiple Airlines
Sat 11/294:20 pmYOW - STL
1 stop8h 37mMultiple Airlines
Deal found 11/12$511
This Kiwi.com deal was found by Cheapflights users on 11/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/2810:57 amSTL - YOW
2 stops29h 16mMultiple Airlines
Thu 1/19:30 amYOW - STL
1 stop14h 03mMultiple Airlines
Deal found 11/12$538
This Kiwi.com deal was found by Cheapflights users on 11/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/204:27 pmSTL - YOW
1 stop23h 46mMultiple Airlines
Thu 12/253:00 pmYOW - STL
2 stops31h 25mMultiple Airlines
Deal found 11/12$571

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Ottawa that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated November 13, 2025.
Use the filters below to find and compare flights from St. Louis to Ottawa that are best for you.

Fly from

St. Louis

Fly to

Ottawa

Route

Depart

Return

Price

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Wed 12/10

1:00 pm-9:18 pm

1 stop7h 18m

Ottawa

Wed 12/17

6:00 am-3:40 pm

2 stops10h 40m

$372

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 11/22

4:13 pm-12:42 am

2 stops31h 29m

Ottawa

Tue 11/25

9:30 am-11:57 pm

1 stop15h 27m

$461

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 11/22

4:13 pm-12:42 am

2 stops31h 29m

Ottawa

Fri 11/28

4:20 pm-11:57 pm

1 stop8h 37m

$493

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 11/22

4:13 pm-12:42 am

2 stops31h 29m

Ottawa

Wed 11/26

9:30 am-11:57 pm

1 stop15h 27m

$508

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sun 12/28

10:57 am-5:13 pm

2 stops29h 16m

Ottawa

Thu 1/1

9:30 am-10:33 pm

1 stop14h 03m

$538

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 12/20

4:27 pm-5:13 pm

1 stop23h 46m

Ottawa

Thu 12/25

9:30 am-9:45 am

1 stop25h 15m

$575

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 11/22

6:43 pm-10:26 am

1 stop14h 43m

Ottawa

Fri 11/28

9:15 am-3:29 pm

1 stop7h 14m

$675

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 11/22

6:43 pm-10:26 am

1 stop14h 43m

Ottawa

Wed 11/26

10:20 am-3:29 pm

1 stop6h 09m

$675

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 11/22

6:43 pm-10:26 am

1 stop14h 43m

Ottawa

Thu 11/27

10:20 am-3:29 pm

1 stop6h 09m

$675

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/12

Compare providers for flights from St. Louis to Ottawa

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Ottawa in November.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on St. Louis-Ottawa flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on St. Louis-Ottawa flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from St. Louis-Ottawa flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Ottawa flights, Cheapflights users trust eDreams the most. eDreams has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Ottawa flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from St. Louis to Ottawa

Have a flexible travel schedule? Discover the best time to fly to Ottawa from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

What is the cheapest month to book a flight from St. Louis to Ottawa?

Currently, July is the cheapest month in which you can book a flight from St. Louis to Ottawa (average of $218). Flying from St. Louis to Ottawa in November is currently the most expensive (average of $608). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

Reviews of airlines servicing Ottawa

Get insights into the airlines that provide service to Ottawa. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Ottawa. Reviews last updated November 13, 2025.
Get a feel of what it's like to fly with United Airlines and Air Canada from St. Louis to Ottawa by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,017 reviews

Comfort

7.3

Crew

8.1

Food

6.6

Boarding

7.7

Entertainment

7.1

Overall

7.4

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
United Airlines
7.4
Good
9,017 reviews
United Airlines
7.4
Good
9,017 reviews

Comfort

7.3

Crew

8.1

Food

6.6

Boarding

7.7

Entertainment

7.1

Overall

7.4

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Air Canada
7.1
Good
10,448 reviews
United Airlines
7.4
Good
9,017 reviews

Comfort

7.3

Crew

8.1

Food

6.6

Boarding

7.7

Entertainment

7.1

Overall

7.4

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Ottawa. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from St. Louis to Ottawa?

    A quick flight from St. Louis to Ottawa can take about 7h 18m. United Airlines provides one of the quickest options available for as low as $372. St. Louis and Ottawa are separated by a distance of 878 mi.

  • What are the cheapest airlines flying from St. Louis to Ottawa round-trip?

    Currently priced at $330, Air Canada will fly you from St. Louis to Ottawa and back. In addition to Air Canada, many other airlines offer competitively priced options for your trip. Check Cheapflights for deals on United Airlines for as low as $362.

  • Can I find deals for flights from St. Louis to Ottawa that include hotel bookings?

    Yes. In addition to deals on St. Louis to Ottawa flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Ottawa?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Ottawa.

  • Can I find deals for business class flights from St. Louis to Ottawa?

    Yes. Cheapflights offers flight deals from St. Louis to Ottawa by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

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

    Currently, July is the cheapest month in which you can book a flight from St. Louis to Ottawa (average of $218). Flying from St. Louis to Ottawa in November is currently the most expensive (average of $608). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Ottawa?

Book flights to Ottawa if you plan to visit one of these locations
Gatineau
Petawawa

Browse thousands of different options on Cheapflights for your next trip

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Top 2 airlines flying from St. Louis to Ottawa

Discover the top 2 airlines that operate flights from St. Louis to Ottawa. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated November 13, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$330Average$834FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$362Average$824FlexibilityNo cancel feeOn-time69%

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