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$231+ Cheap flights from St. Louis (STL) to Ottawa (YOW)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 7/24. Fares are subject to change and may not be available on all flights or dates of travel.
STL — YOW
Jul 7 — Jul 141
Mon 7/7
Mon 7/14
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 July 2, 2025.

Round-trip from

$425
(Kiwi.com)

One-way from

$231
(Kiwi.com)
From Lambert-St Louis to Ottawa
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One-way flight 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 July 2, 2025.

This Kiwi.com deal was found by Cheapflights users on 6/30. 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.
Thu 8/1410:37 amSTL - YOW
1 stop29h 38mMultiple Airlines
Thu 8/214:25 pmYOW - STL
1 stop22h 56mMultiple Airlines
Deal found 6/30$425
This United Airlines deal was found by Cheapflights users on 7/2. 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.
Sat 8/165:15 amSTL - YOW
2 stops15h 50mUnited Airlines
Sat 8/235:15 amYOW - STL
2 stops19h 38mUnited Airlines
Deal found 7/2$669
This Air Canada deal was found by Cheapflights users on 7/1. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/141:30 pmSTL - YOW
1 stop5h 45mAir Canada
Thu 8/212:25 pmYOW - STL
1 stop6h 35mAir Canada
Deal found 7/1$690
This Delta deal was found by Cheapflights users on 7/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/211:29 pmSTL - YOW
2 stops9h 53mDelta
Mon 7/285:55 amYOW - STL
2 stops12h 13mDelta
Deal found 7/2$880

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 July 2, 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

Thu 8/14

10:37 am-5:15 pm

1 stop29h 38m

Ottawa

Thu 8/21

4:25 pm-2:21 pm

1 stop22h 56m

$425

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 8/16

5:15 am-10:05 pm

2 stops15h 50m

Ottawa

Sat 8/23

5:15 am-11:53 pm

2 stops19h 38m

$669

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Thu 8/14

1:30 pm-8:15 pm

1 stop5h 45m

Ottawa

Thu 8/21

2:25 pm-8:00 pm

1 stop6h 35m

$690

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Mon 7/21

1:29 pm-12:22 am

2 stops9h 53m

Ottawa

Mon 7/28

5:55 am-5:08 pm

2 stops12h 13m

$880

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Thu 7/24

5:26 pm-5:15 pm

1 stop22h 49m

$231

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/1

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, January is the cheapest month in which you can book a flight from St. Louis to Ottawa (average of $294). Flying from St. Louis to Ottawa in September is currently the most expensive (average of $428). 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 July 2, 2025.
Get a feel of what it's like to fly with 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.
Air Canada
7.1
Good
9,669 reviews

Boarding

7.3

Food

6.3

Overall

7.1

Crew

7.8

Entertainment

6.8

Comfort

7.1

Reviews

1 / 20
10.0
Excellent

rita,May 2025

YWG - YYZ

All was good just disappeared about our flight on our original day May 27 the being cancelled
Air Canada
7.1
Good
9,669 reviews
Air Canada
7.1
Good
9,669 reviews

Boarding

7.3

Food

6.3

Overall

7.1

Crew

7.8

Entertainment

6.8

Comfort

7.1

Reviews

1 / 20
10.0
Excellent

rita,May 2025

YWG - YYZ

All was good just disappeared about our flight on our original day May 27 the being cancelled

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.

  • What is the cheapest airline to fly from St. Louis to Ottawa round-trip?

    Currently priced at $690, 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.

  • 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, January is the cheapest month in which you can book a flight from St. Louis to Ottawa (average of $294). Flying from St. Louis to Ottawa in September is currently the most expensive (average of $428). 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 St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Gatineau
Petawawa

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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 July 2, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$330Average$812FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$434Average$803FlexibilityNo cancel feeOn-time69%

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