$161+ 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 12/16. Fares are subject to change and may not be available on all flights or dates of travel.
STL — YOW
Oct 31 — Nov 71
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis to Ottawa with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from St. Louis to Ottawa
Cheapest
Best
Last-minute
One-way
Cheapest flights from St. Louis to OttawaExplore 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 October 1, 2026.
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 October 1, 2026.
This Mytrip deal was found by Cheapflights users on 9/27. 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 11/116:44 pm -
2 stops28h 17m
Wed 11/183:05 pm -
2 stops28h 34m
Deal found 9/27![Multiple Airlines logo]()
$539
This Kiwi.com deal was found by Cheapflights users on 9/30. 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.
Fri 10/236:35 pm -
2 stops42h 55m
Sat 10/318:00 am -
1 stop16h 16m
Deal found 9/30![Multiple Airlines logo]()
$543
This Mytrip deal was found by Cheapflights users on 9/30. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/1911:40 am -
3 stops31h 29m
Sun 11/223:25 pm -
2 stops27h 15m
Deal found 9/30![Multiple Airlines logo]()
$557
Best flights from St. Louis to OttawaDiscover carefully curated flight deals from St. Louis to Ottawa that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 1, 2026.
Discover carefully curated flight deals from St. Louis to Ottawa that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 1, 2026.
This Kiwi.com deal was found by Cheapflights users on 9/28. 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.
Tue 11/1010:05 am -
2 stops36h 56m
Fri 11/208:00 am -
1 stop29h 25m
Deal found 9/28![Multiple Airlines logo]()
$728
This United Airlines deal was found by Cheapflights users on 9/30. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/285:00 pm -
1 stop19h 11m
Sat 10/316:00 am -
2 stops11h 59m
Deal found 9/30![United Airlines logo]()
$758
This Air Canada deal was found by Cheapflights users on 9/30. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/74:05 pm -
1 stop6h 50m
Thu 12/1010:05 am -
1 stop6h 21m
Deal found 9/30![Air Canada logo]()
$759
This Kiwi.com deal was found by Cheapflights users on 9/30. 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 11/196:20 am -
1 stop16h 35m
Sun 11/223:25 pm -
2 stops27h 15m
Deal found 9/30![Multiple Airlines logo]()
$753
Last-minute flights from St. Louis to OttawaDiscover last-minute flight deals from St. Louis to Ottawa. Data last updated October 1, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Ottawa. Data last updated October 1, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 9/30. 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.
Fri 10/236:35 pm -
2 stops42h 55m
Sat 10/318:00 am -
1 stop16h 16m
Deal found 9/30![Multiple Airlines logo]()
$543
This Kiwi.com deal was found by Cheapflights users on 9/27. 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 10/254:30 pm -
2 stops21h 15m
Sun 11/18:00 am -
1 stop16h 16m
Deal found 9/27![Multiple Airlines logo]()
$704
This United Airlines deal was found by Cheapflights users on 9/29. 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 10/285:00 pm -
1 stop19h 11m
Sat 10/316:00 am -
2 stops11h 59m
Deal found 9/29![United Airlines logo]()
$758
One-way flights from St. Louis to OttawaSearch for one-way flight options from St. Louis to Ottawa. Find affordable one-way fares based on user searches. Data last updated October 1, 2026.
Search for one-way flight options from St. Louis to Ottawa. Find affordable one-way fares based on user searches. Data last updated October 1, 2026.
This Kiwi.com deal was found by Cheapflights users on 9/27. 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.
Wed 12/1612:02 pm -
2 stops35h 05m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/27![Multiple Airlines logo]()
$161
This Kiwi.com deal was found by Cheapflights users on 9/27. 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 10/254:30 pm -
2 stops21h 15m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/27![Multiple Airlines logo]()
$322
This United Airlines deal was found by Cheapflights users on 9/27. 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 10/257:30 am -
1 stop5h 39m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/27![United Airlines logo]()
$370
This United Airlines deal was found by Cheapflights users on 9/29. 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.
Fri 11/135:00 am -
1 stop8h 09m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/29![United Airlines logo]()
$407
Find 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 October 1, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $539 (Mytrip) |
One-way from | $161 (Kiwi.com) |
Popular in | September |
Cheapest in | June |
Average price | $630 |
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 7,457,451 searches. Data last updated October 1, 2026.
Use the filters below to find and compare flights from St. Louis to Ottawa that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Wed 12/16
6:13 pm-3:39 pm
1 stop20h 26m
Ottawa
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$254
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Sun 10/25
4:30 pm-2:45 pm
2 stops21h 15m
Ottawa
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$322
Quickest round-trip
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Sun 10/25
7:30 am-2:09 pm
1 stop5h 39m
Ottawa
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$370
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Fri 11/13
5:00 am-2:09 pm
1 stop8h 09m
Ottawa
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$407
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Tue 11/10
10:05 am-12:01 am
2 stops36h 56m
Ottawa
Fri 11/20
8:00 am-12:25 pm
1 stop29h 25m
$728
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Thu 11/19
6:20 am-11:55 pm
1 stop16h 35m
Ottawa
Sun 11/22
3:25 pm-5:40 pm
2 stops27h 15m
$753
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Wed 10/28
5:00 pm-1:11 pm
1 stop19h 11m
Ottawa
Sat 10/31
6:00 am-4:59 pm
2 stops11h 59m
$758
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Mon 12/7
4:05 pm-11:55 pm
1 stop6h 50m
Ottawa
Thu 12/10
10:05 am-3:26 pm
1 stop6h 21m
$759
Sorted by cheapest first
- Most accurate provider: When it comes to deals on St. Louis-Ottawa flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Ottawa flight deals on Cheapflights vs. FlightHub >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 FlightHub the most. FlightHub 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.
STL-YOW
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.
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 October 1, 2026.
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.
Food
6.7
Boarding
7.7
Comfort
7.3
Entertainment
7.1
Crew
8.1
Overall
7.4
Reviews
1 / 20
6.0
GoodMiz,Oct 2024
EWR - YYZ
Food
6.7
Boarding
7.7
Comfort
7.3
Entertainment
7.1
Crew
8.1
Overall
7.4
Reviews
1 / 20
6.0
GoodMiz,Oct 2024
EWR - YYZ
Food
6.7
Boarding
7.7
Comfort
7.3
Entertainment
7.1
Crew
8.1
Overall
7.4
Reviews
1 / 20
6.0
GoodMiz,Oct 2024
EWR - YYZ
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.
Traveling to a place near Ottawa?
Book flights to Ottawa if you plan to visit one of these locationsGatineau
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St. Louis and Ottawa flights
Browse other St. Louis and Ottawa flight options. Last updated on October 1, 2026.
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Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
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 7,457,451 searches. Data last updated October 1, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$139 | Average$489 | FlexibilityNo cancel fee | On-time67% | |
| Cheapest$203 | Average$630 | FlexibilityNo cancel fee | On-time69% |