$281+ 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 11/22. Fares are subject to change and may not be available on all flights or dates of travel.
STL — YOW
Nov 9 — Nov 161
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
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Best
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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 10, 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 10, 2026.
This Kiwi.com deal was found by Cheapflights users on 10/9. 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 11/194:26 pm -
2 stops21h 06m
Sun 11/228:00 am -
1 stop16h 59m
Deal found 10/9![Multiple Airlines logo]()
$650
This United Airlines deal was found by Cheapflights users on 10/7. 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 10/286:09 am -
1 stop6h 02m
Sat 10/316:15 am -
1 stop6h 57m
Deal found 10/7![United Airlines logo]()
$719
This Mytrip deal was found by Cheapflights users on 10/8. 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.
Sun 11/226:05 pm -
3 stops25h 02m
Sun 11/293:30 pm -
3 stops33h 29m
Deal found 10/8![Multiple Airlines logo]()
$723
This United Airlines deal was found by Cheapflights users on 10/6. 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 11/258:30 am -
1 stop4h 39m
Sun 11/296:15 am -
1 stop6h 55m
Deal found 10/6![United Airlines logo]()
$730
This United Airlines deal was found by Cheapflights users on 10/7. 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 12/66:30 am -
2 stops14h 26m
Sat 12/126:00 am -
2 stops13h 16m
Deal found 10/7![United Airlines logo]()
$734
This Kiwi.com deal was found by Cheapflights users on 10/9. 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 10/244:30 pm -
1 stop23h 14m
Sun 11/13:30 pm -
2 stops27h 10m
Deal found 10/9![Multiple Airlines logo]()
$745
This United Airlines deal was found by Cheapflights users on 10/6. 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 11/206:00 am -
1 stop6h 11m
Fri 11/276:00 am -
1 stop5h 48m
Deal found 10/6![United Airlines logo]()
$749
This Kiwi.com deal was found by Cheapflights users on 10/6. 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 11/256:35 pm -
2 stops18h 57m
Sun 11/298:00 am -
1 stop16h 59m
Deal found 10/6![Multiple Airlines logo]()
$754
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 10, 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 10, 2026.
This United Airlines deal was found by Cheapflights users on 10/7. 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 12/66:10 am -
1 stop6h 01m
Sat 12/123:10 pm -
1 stop8h 05m
Deal found 10/7![United Airlines logo]()
$719
This Mytrip deal was found by Cheapflights users on 10/9. 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 11/1911:29 am -
3 stops28h 55m
Sun 11/228:40 am -
3 stops27h 23m
Deal found 10/9![Multiple Airlines logo]()
$772
This United Airlines deal was found by Cheapflights users on 10/7. 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 10/286:09 am -
1 stop6h 02m
Sat 10/316:15 am -
1 stop6h 57m
Deal found 10/7![United Airlines logo]()
$719
This United Airlines deal was found by Cheapflights users on 10/8. 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 11/225:00 am -
2 stops13h 27m
Sun 11/296:15 am -
1 stop6h 55m
Deal found 10/8![United Airlines logo]()
$729
This United Airlines deal was found by Cheapflights users on 10/9. 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.
Mon 12/71:18 pm -
1 stop6h 58m
Thu 12/109:45 am -
2 stops10h 41m
Deal found 10/9![United Airlines logo]()
$729
This United Airlines deal was found by Cheapflights users on 10/6. 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 11/258:30 am -
1 stop4h 39m
Sun 11/296:15 am -
1 stop6h 55m
Deal found 10/6![United Airlines logo]()
$730
This United Airlines deal was found by Cheapflights users on 10/8. 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 10/248:00 am -
1 stop8h 16m
Sun 11/16:15 am -
1 stop10h 28m
Deal found 10/8![United Airlines logo]()
$774
Last-minute flights from St. Louis to OttawaDiscover last-minute flight deals from St. Louis to Ottawa. Data last updated October 10, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Ottawa. Data last updated October 10, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 10/9. 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 10/244:30 pm -
1 stop23h 14m
Sun 11/13:30 pm -
2 stops27h 10m
Deal found 10/9![Multiple Airlines logo]()
$745
This United Airlines deal was found by Cheapflights users on 10/7. 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 10/286:09 am -
1 stop6h 02m
Sat 10/316:15 am -
1 stop6h 57m
Deal found 10/7![United Airlines logo]()
$719
This Kiwi.com deal was found by Cheapflights users on 10/9. 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 11/194:26 pm -
2 stops21h 06m
Sun 11/228:00 am -
1 stop16h 59m
Deal found 10/9![Multiple Airlines logo]()
$650
This United Airlines deal was found by Cheapflights users on 10/6. 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 11/206:00 am -
1 stop6h 11m
Fri 11/276:00 am -
1 stop5h 48m
Deal found 10/6![United Airlines logo]()
$749
This Mytrip deal was found by Cheapflights users on 10/8. 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.
Sun 11/226:05 pm -
3 stops25h 02m
Sun 11/293:30 pm -
3 stops33h 29m
Deal found 10/8![Multiple Airlines logo]()
$723
This United Airlines deal was found by Cheapflights users on 10/6. 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 11/258:30 am -
1 stop4h 39m
Sun 11/296:15 am -
1 stop6h 55m
Deal found 10/6![United Airlines logo]()
$730
This Kiwi.com deal was found by Cheapflights users on 10/6. 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 11/256:35 pm -
2 stops18h 57m
Sun 11/298:00 am -
1 stop16h 59m
Deal found 10/6![Multiple Airlines logo]()
$754
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 10, 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 10, 2026.
This Kiwi.com deal was found by Cheapflights users on 10/8. 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 11/226:05 pm -
3 stops46h 19m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/8![Multiple Airlines logo]()
$281
This United Airlines deal was found by Cheapflights users on 10/8. 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 11/221:00 pm -
1 stop5h 27m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/8![United Airlines logo]()
$318
This Kiwi.com deal was found by Cheapflights users on 10/7. 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 10/247:42 pm -
3 stops44h 38m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Multiple Airlines logo]()
$357
This United Airlines deal was found by Cheapflights users on 10/7. 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 10/2412:14 pm -
1 stop9h 21m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![United Airlines logo]()
$386
This American Airlines deal was found by Cheapflights users on 10/7. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/245:00 am -
3 stops14h 00m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![American Airlines logo]()
$508
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 10, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $650 (Kiwi.com) |
One-way from | $281 (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 10, 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
Sun 11/22
6:05 pm-5:24 pm
3 stops46h 19m
Ottawa
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$281
Quickest round-trip
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Sun 11/22
1:00 pm-7:27 pm
1 stop5h 27m
Ottawa
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$318
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Sat 10/24
7:42 pm-5:20 pm
3 stops44h 38m
Ottawa
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$357
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Sat 10/24
12:14 pm-10:35 pm
1 stop9h 21m
Ottawa
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$386
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Sat 10/24
5:00 am-8:00 pm
3 stops14h 00m
Ottawa
Wed 12/31
12:00 am-11:00 pm
Nonstop0h 00m
$508
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Sun 12/6
6:10 am-1:11 pm
1 stop6h 01m
Ottawa
Sat 12/12
3:10 pm-10:15 pm
1 stop8h 05m
$719
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Wed 10/28
6:09 am-1:11 pm
1 stop6h 02m
Ottawa
Sat 10/31
6:15 am-12:12 pm
1 stop6h 57m
$719
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Sun 11/22
5:00 am-7:27 pm
2 stops13h 27m
Ottawa
Sun 11/29
6:15 am-12:10 pm
1 stop6h 55m
$729
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Mon 12/7
1:18 pm-9:16 pm
1 stop6h 58m
Ottawa
Thu 12/10
9:45 am-7:26 pm
2 stops10h 41m
$729
St. LouisOttawa
STL Lambert-St Louis - YOW Ottawa
STLYOW
Lambert-St Louis
Wed 11/25
8:30 am-2:09 pm
1 stop4h 39m
Ottawa
Sun 11/29
6:15 am-12:10 pm
1 stop6h 55m
$730
Showing 1-10 of 12 resultsSorted 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 10, 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
Comfort
7.3
Crew
8.1
Entertainment
7.1
Boarding
7.7
Overall
7.4
Reviews
1 / 20
6.0
GoodMiz,Oct 2024
EWR - YYZ
Food
6.7
Comfort
7.3
Crew
8.1
Entertainment
7.1
Boarding
7.7
Overall
7.4
Reviews
1 / 20
6.0
GoodMiz,Oct 2024
EWR - YYZ
Food
6.7
Comfort
7.3
Crew
8.1
Entertainment
7.1
Boarding
7.7
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 10, 2026.
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Browse through other flights departing from St. Louis. Flights are based on user searches made on Cheapflights and were last updated on October 10, 2026.
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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 7,457,451 searches. Data last updated October 10, 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% |