$289+ Cheap flights from Ottawa (YOW) to St. Louis (STL)
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 11/6. Fares are subject to change and may not be available on all flights or dates of travel.
YOW — STL
Oct 24 — Oct 311
Round-trip
1 adult, Economy
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Find cheap flights from Ottawa to St. Louis 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
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
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 Ottawa to St. Louis
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Best
Last-minute
One-way
Cheapest flights from Ottawa to St. LouisExplore the most affordable flight options available from Ottawa to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 24, 2026.
Explore the most affordable flight options available from Ottawa to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 24, 2026.
This Mytrip deal was found by Cheapflights users on 9/22. 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.
Fri 10/234:00 pm -
3 stops27h 57m
Sat 10/317:59 pm -
3 stops28h 02m
Deal found 9/22![Multiple Airlines logo]()
$561
This United Airlines deal was found by Cheapflights users on 9/22. 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.
Thu 10/156:05 am -
1 stop10h 55m
Mon 10/191:29 pm -
1 stop7h 06m
Deal found 9/22![United Airlines logo]()
$588
This United Airlines deal was found by Cheapflights users on 9/21. 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.
Thu 10/156:00 am -
3 stops16h 21m
Sun 10/183:11 pm -
1 stop5h 24m
Deal found 9/21![United Airlines logo]()
$590
This Air Canada deal was found by Cheapflights users on 9/19. 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 10/152:50 pm -
1 stop4h 51m
Mon 10/192:40 pm -
1 stop5h 40m
Deal found 9/19![Air Canada logo]()
$597
This Air Canada deal was found by Cheapflights users on 9/19. 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.
Fri 10/162:50 pm -
1 stop4h 51m
Mon 10/264:05 pm -
1 stop6h 50m
Deal found 9/19![Air Canada logo]()
$604
This United Airlines deal was found by Cheapflights users on 9/22. 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 10/2310:00 am -
2 stops12h 21m
Sat 10/318:30 am -
2 stops12h 26m
Deal found 9/22![United Airlines logo]()
$616
This United Airlines deal was found by Cheapflights users on 9/22. 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 10/103:10 pm -
1 stop7h 27m
Thu 10/157:30 am -
1 stop8h 08m
Deal found 9/22![United Airlines logo]()
$638
This American Airlines deal was found by Cheapflights users on 9/19. 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.
Fri 10/167:00 am -
2 stops14h 57m
Mon 10/2611:31 am -
2 stops29h 27m
Deal found 9/19![American Airlines logo]()
$644
This United Airlines deal was found by Cheapflights users on 9/19. 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 10/96:00 am -
2 stops10h 43m
Thu 10/157:30 am -
1 stop8h 08m
Deal found 9/19![United Airlines logo]()
$646
Best flights from Ottawa to St. LouisDiscover carefully curated flight deals from Ottawa to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 24, 2026.
Discover carefully curated flight deals from Ottawa to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 24, 2026.
This United Airlines deal was found by Cheapflights users on 9/22. 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.
Thu 10/156:05 am -
1 stop10h 55m
Mon 10/191:29 pm -
1 stop7h 06m
Deal found 9/22![United Airlines logo]()
$588
This Air Canada deal was found by Cheapflights users on 9/21. 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.
Fri 10/162:50 pm -
1 stop4h 51m
Mon 10/264:05 pm -
1 stop6h 50m
Deal found 9/21![Air Canada logo]()
$604
This United Airlines deal was found by Cheapflights users on 9/22. 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 10/236:01 pm -
1 stop15h 47m
Sat 10/318:30 am -
2 stops12h 26m
Deal found 9/22![United Airlines logo]()
$590
This United Airlines deal was found by Cheapflights users on 9/22. 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 10/236:01 pm -
1 stop15h 47m
Sun 11/15:00 am -
1 stop8h 09m
Deal found 9/22![United Airlines logo]()
$590
This United Airlines deal was found by Cheapflights users on 9/21. 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.
Thu 10/156:00 am -
3 stops16h 21m
Sun 10/183:11 pm -
1 stop5h 24m
Deal found 9/21![United Airlines logo]()
$590
This United Airlines deal was found by Cheapflights users on 9/21. 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 10/309:45 am -
2 stops8h 14m
Sat 10/3111:15 am -
2 stops9h 41m
Deal found 9/21![United Airlines logo]()
$590
This United Airlines deal was found by Cheapflights users on 9/22. 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 11/186:00 am -
2 stops9h 34m
Sun 11/221:08 pm -
1 stop7h 08m
Deal found 9/22![United Airlines logo]()
$590
Last-minute flights from Ottawa to St. LouisDiscover last-minute flight deals from Ottawa to St. Louis. Data last updated September 24, 2026 and is based on user searches.
Discover last-minute flight deals from Ottawa to St. Louis. Data last updated September 24, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 9/19. 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 10/96:00 am -
2 stops10h 43m
Thu 10/157:30 am -
1 stop8h 08m
Deal found 9/19![United Airlines logo]()
$646
This United Airlines deal was found by Cheapflights users on 9/22. 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 10/106:00 am -
2 stops10h 43m
Thu 10/1511:35 am -
2 stops11h 19m
Deal found 9/22![United Airlines logo]()
$638
This United Airlines deal was found by Cheapflights users on 9/22. 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.
Thu 10/156:05 am -
1 stop10h 55m
Mon 10/191:29 pm -
1 stop7h 06m
Deal found 9/22![United Airlines logo]()
$588
This United Airlines deal was found by Cheapflights users on 9/21. 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.
Thu 10/156:00 am -
3 stops16h 21m
Sun 10/183:11 pm -
1 stop5h 24m
Deal found 9/21![United Airlines logo]()
$590
This Air Canada deal was found by Cheapflights users on 9/19. 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 10/152:50 pm -
1 stop4h 51m
Mon 10/192:40 pm -
1 stop5h 40m
Deal found 9/19![Air Canada logo]()
$597
This Air Canada deal was found by Cheapflights users on 9/19. 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.
Fri 10/162:50 pm -
1 stop4h 51m
Mon 10/264:05 pm -
1 stop6h 50m
Deal found 9/19![Air Canada logo]()
$604
This American Airlines deal was found by Cheapflights users on 9/19. 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.
Fri 10/167:00 am -
2 stops14h 57m
Mon 10/2611:31 am -
2 stops29h 27m
Deal found 9/19![American Airlines logo]()
$644
This Mytrip deal was found by Cheapflights users on 9/22. 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.
Fri 10/234:00 pm -
3 stops27h 57m
Sat 10/317:59 pm -
3 stops28h 02m
Deal found 9/22![Multiple Airlines logo]()
$561
This United Airlines deal was found by Cheapflights users on 9/22. 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 10/2310:00 am -
2 stops12h 21m
Sat 10/318:30 am -
2 stops12h 26m
Deal found 9/22![United Airlines logo]()
$616
One-way flights from Ottawa to St. LouisSearch for one-way flight options from Ottawa to St. Louis. Find affordable one-way fares based on user searches. Data last updated September 24, 2026.
Search for one-way flight options from Ottawa to St. Louis. Find affordable one-way fares based on user searches. Data last updated September 24, 2026.
This Kiwi.com deal was found by Cheapflights users on 9/22. 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 11/65:40 pm -
3 stops26h 34m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/22![Multiple Airlines logo]()
$289
This United Airlines deal was found by Cheapflights users on 9/22. 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 11/66:00 am -
2 stops16h 40m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/22![United Airlines logo]()
$324
Find flight deals from Ottawa to St. Louis
Discover tips and strategies to find the most affordable flight options for your journey from Ottawa (YOW) to St. Louis (STL). 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 September 24, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $561 (Mytrip) |
One-way from | $289 (Kiwi.com) |
Popular in | August |
Cheapest in | May |
Average price | $352 |
Cheapflights Fare Finder
Customize your flight search to find flights from Ottawa to St. Louis 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 September 24, 2026.
Use the filters below to find and compare flights from Ottawa to St. Louis that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
OttawaSt. Louis
YOW Ottawa - STL Lambert-St Louis
YOWSTL
Ottawa
Fri 11/6
5:40 pm-7:14 pm
3 stops26h 34m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$289
Quickest round-trip
OttawaSt. Louis
YOW Ottawa - STL Lambert-St Louis
YOWSTL
Ottawa
Fri 11/6
6:00 am-4:17 pm
1 stop11h 17m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$324
OttawaSt. Louis
YOW Ottawa - STL Lambert-St Louis
YOWSTL
Ottawa
Thu 10/15
6:05 am-4:00 pm
1 stop10h 55m
Lambert-St Louis
Mon 10/19
1:29 pm-9:35 pm
1 stop7h 06m
$588
OttawaSt. Louis
YOW Ottawa - STL Lambert-St Louis
YOWSTL
Ottawa
Fri 10/23
6:01 pm-8:48 am
1 stop15h 47m
Lambert-St Louis
Sat 10/31
8:30 am-9:56 pm
2 stops12h 26m
$590
OttawaSt. Louis
YOW Ottawa - STL Lambert-St Louis
YOWSTL
Ottawa
Fri 10/23
6:01 pm-8:48 am
1 stop15h 47m
Lambert-St Louis
Sun 11/1
5:00 am-2:09 pm
1 stop8h 09m
$590
OttawaSt. Louis
YOW Ottawa - STL Lambert-St Louis
YOWSTL
Ottawa
Thu 10/15
6:00 am-9:21 pm
3 stops16h 21m
Lambert-St Louis
Sun 10/18
3:11 pm-9:35 pm
1 stop5h 24m
$590
OttawaSt. Louis
YOW Ottawa - STL Lambert-St Louis
YOWSTL
Ottawa
Fri 10/30
9:45 am-4:59 pm
2 stops8h 14m
Lambert-St Louis
Sat 10/31
11:15 am-9:56 pm
2 stops9h 41m
$590
OttawaSt. Louis
YOW Ottawa - STL Lambert-St Louis
YOWSTL
Ottawa
Wed 11/18
6:00 am-2:34 pm
2 stops9h 34m
Lambert-St Louis
Sun 11/22
1:08 pm-9:16 pm
1 stop7h 08m
$590
OttawaSt. Louis
YOW Ottawa - STL Lambert-St Louis
YOWSTL
Ottawa
Fri 10/16
2:50 pm-6:41 pm
1 stop4h 51m
Lambert-St Louis
Mon 10/26
4:05 pm-11:55 pm
1 stop6h 50m
$604
Sorted by cheapest first
- Most accurate provider: When it comes to deals on Ottawa-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ottawa-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ottawa-St. Louis flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Ottawa-St. Louis 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 Ottawa-St. Louis 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 Ottawa to St. Louis
Have a flexible travel schedule? Discover the best time to fly to St. Louis from Ottawa with our price prediction graph.
YOW-STL
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 St. Louis
Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated September 24, 2026.
Read through reviews of airlines operating flights from Ottawa to St. Louis, such as Air Canada. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
6.8
Overall
7.1
Comfort
7.1
Food
6.3
Boarding
7.3
Crew
7.8
Reviews
1 / 20
2.0
MediocreSylvia,Aug 2026
YYZ - PHL
Entertainment
6.8
Overall
7.1
Comfort
7.1
Food
6.3
Boarding
7.3
Crew
7.8
Reviews
1 / 20
2.0
MediocreSylvia,Aug 2026
YYZ - PHL
Related info for your journey
Find useful and relevant information for your journey from Ottawa to St. Louis. 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 St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsFairview Heights
O'Fallon
Fenton
Swansea
Eureka
Wentzville
Maryland Heights
Collinsville
Edwardsville
Glencoe
Chesterfield
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Complete your trip to St. Louis by adding a car rental and/or hotel reservation to your travel itinerary.
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Ottawa and St. Louis flights
Browse other Ottawa and St. Louis flight options. Last updated on September 24, 2026.
Other flights from Ottawa
Browse through other flights departing from Ottawa. Flights are based on user searches made on Cheapflights and were last updated on September 24, 2026.
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Check out other popular destinations found by fellow travelers in 2026
Other flights to St. Louis
Explore flights to St. Louis departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on September 24, 2026.
Top airline flying from Ottawa to St. Louis
Discover the top airline that operate flights from Ottawa to St. Louis. 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 September 24, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$285 | Average$375 | FlexibilityNo cancel fee | On-time67% |