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$260+ 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 6/25. Fares are subject to change and may not be available on all flights or dates of travel.
STL — YOW
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
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 June 12, 2025.

Round-trip from

$415
(Mytrip)

One-way from

$260
(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 June 12, 2025.

This Mytrip deal was found by Cheapflights users on 6/11. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/911:24 amSTL - YOW
1 stop28h 42mMultiple Airlines
Wed 7/1611:00 amYOW - STL
2 stops23h 52mMultiple Airlines
Deal found 6/11$415
This Air Canada deal was found by Cheapflights users on 6/11. 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.
Sun 7/69:15 amSTL - YOW
1 stop6h 50mAir Canada
Thu 7/102:40 pmYOW - STL
1 stop7h 10mAir Canada
Deal found 6/11$746
This United Airlines deal was found by Cheapflights users on 6/11. 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.
Sun 7/66:33 amSTL - YOW
1 stop6h 31mUnited Airlines
Thu 7/106:33 amYOW - STL
1 stop6h 54mUnited Airlines
Deal found 6/11$754
This FlightHub deal was found by Cheapflights users on 6/10. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/36:00 amSTL - YOW
2 stops17h 22mWestJet
Mon 7/75:55 amYOW - STL
2 stops18h 58mWestJet
Deal found 6/10$1,049

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 June 12, 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 7/9

11:24 am-5:06 pm

1 stop28h 42m

Ottawa

Wed 7/16

11:00 am-9:52 am

2 stops23h 52m

$415

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sun 7/6

9:15 am-5:05 pm

1 stop6h 50m

Ottawa

Thu 7/10

2:40 pm-8:50 pm

1 stop7h 10m

$746

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sun 7/6

6:33 am-2:04 pm

1 stop6h 31m

Ottawa

Thu 7/10

6:33 am-12:27 pm

1 stop6h 54m

$754

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Thu 7/3

6:00 am-12:22 am

2 stops17h 22m

Ottawa

Mon 7/7

5:55 am-11:53 pm

2 stops18h 58m

$1,049

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Wed 6/25

5:47 pm-5:06 pm

1 stop22h 19m

$260

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Thu 6/19

5:00 am-5:29 pm

1 stop11h 29m

$415

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/11

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.

Rainfall in Ottawa by month

Plan your trip to Ottawa by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Ottawa ranges from 2.0 - 3.7 inches per month. June is typically the wettest month, when rainfall can reach 3.7 in. February is typically the driest time to visit Ottawa when rainfall is around 2.0 in.

Temperature in Ottawa by month

Plan your trip to Ottawa by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Ottawa, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 69.8 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 14.0 F).

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 June 12, 2025.
United Airlines
7.4
Good
8,790 reviews

Overall

7.4

Entertainment

7.0

Food

6.6

Boarding

7.7

Comfort

7.3

Crew

8.1

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
United Airlines
7.4
Good
8,790 reviews
United Airlines
7.4
Good
8,790 reviews

Overall

7.4

Entertainment

7.0

Food

6.6

Boarding

7.7

Comfort

7.3

Crew

8.1

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
WestJet
7.2
Good
2,868 reviews
United Airlines
7.4
Good
8,790 reviews

Overall

7.4

Entertainment

7.0

Food

6.6

Boarding

7.7

Comfort

7.3

Crew

8.1

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
Air Canada
7.1
Good
9,531 reviews
United Airlines
7.4
Good
8,790 reviews

Overall

7.4

Entertainment

7.0

Food

6.6

Boarding

7.7

Comfort

7.3

Crew

8.1

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??

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

    Currently priced at $746, 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. Search Cheapflights for deals from United Airlines and WestJet - these airlines can fly you to your destination from $754 and $1,049, respectively.

  • 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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$330Average$809FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$434Average$822FlexibilityNo cancel feeOn-time69%

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