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St. Louis

$272+ Cheap flights from Ottawa (YOW) to St. Louis (STL)

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 6/8. Fares are subject to change and may not be available on all flights or dates of travel.
YOW — STL
Apr 30 — May 71
Wed 4/30
Wed 5/7
1 adult, Economy
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Cheap 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 April 25, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$430
(Mytrip)

One-way from

$272
(Air Canada)

Popular in

August

Cheapest in

September

Average price

$705
Provider with most accurate pricing for Ottawa-Lambert-St Louis flight deals.
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Provider most trusted by Cheapflights users for Ottawa-Lambert-St Louis flights.
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From Ottawa to Lambert-St Louis
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One-way flight from Ottawa to Lambert-St Louis
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Highest demand for flights based on searches. 1% potential increase in price ($8 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($10 potential savings vs. average RT price).
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Average for round-trip flights in April 2025
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Find flight deals from Ottawa to St. Louis

Cheapest flights from Ottawa to St. Louis
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 April 25, 2025.

This Mytrip deal was found by Cheapflights users on 4/25. 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 5/303:50 pmYOW - STL
1 stop18h 25mMultiple Airlines
Sat 5/3112:15 pmSTL - YOW
3 stops27h 49mMultiple Airlines
Deal found 4/25$430
This Air Canada deal was found by Cheapflights users on 4/24. 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 6/202:25 pmYOW - STL
1 stop6h 33mAir Canada
Mon 6/231:30 pmSTL - YOW
1 stop5h 45mAir Canada
Deal found 4/24$496
This Delta deal was found by Cheapflights users on 4/24. 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.
Fri 6/205:55 amYOW - STL
2 stops12h 24mDelta
Mon 6/234:07 pmSTL - YOW
2 stops7h 15mDelta
Deal found 4/24$532
This United Airlines deal was found by Cheapflights users on 4/24. 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 5/235:15 amYOW - STL
2 stops11h 15mUnited Airlines
Fri 5/305:00 amSTL - YOW
1 stop8h 04mUnited Airlines
Deal found 4/24$543

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 2,558,603 searches. Data last updated April 25, 2025.
Use the filters below to find and compare flights from Ottawa to St. Louis that are best for you.

Fly from

Ottawa

Fly to

St. Louis

Route

Depart

Return

Price

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Fri 5/30

3:50 pm-9:15 am

1 stop18h 25m

Lambert-St Louis

Sat 5/31

12:15 pm-5:04 pm

3 stops27h 49m

$430

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Fri 6/20

2:25 pm-7:58 pm

1 stop6h 33m

Lambert-St Louis

Mon 6/23

1:30 pm-8:15 pm

1 stop5h 45m

$496

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Fri 6/20

5:55 am-5:19 pm

2 stops12h 24m

Lambert-St Louis

Mon 6/23

4:07 pm-12:22 am

2 stops7h 15m

$532

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Fri 5/23

5:15 am-3:30 pm

2 stops11h 15m

Lambert-St Louis

Fri 5/30

5:00 am-2:04 pm

1 stop8h 04m

$543

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Sun 6/8

2:40 pm-7:58 pm

1 stop6h 18m

$272

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Sun 6/8

7:00 am-11:37 pm

2 stops17h 37m

$326

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/24

Compare providers for flights from Ottawa to St. Louis

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ottawa to St. Louis in April.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*2 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • 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 eDreams the most. eDreams 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.
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 Ottawa to St. Louis

What is the cheapest month to book a flight from Ottawa to St. Louis?

Currently, August is the cheapest month in which you can book a flight from Ottawa to St. Louis (average of $311). Flying from Ottawa to St. Louis in March is currently the most expensive (average of $356). 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 St. Louis by month

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

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

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

If weather is an important factor for your trip to St. Louis, 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 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

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 April 25, 2025.
Delta
8.0
Very good
7,920 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.9

Comfort

7.9

Overall

8.0

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Delta
8.0
Very good
7,920 reviews
Delta
8.0
Very good
7,920 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.9

Comfort

7.9

Overall

8.0

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
United Airlines
7.4
Good
8,685 reviews
Delta
8.0
Very good
7,920 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.9

Comfort

7.9

Overall

8.0

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Air Canada
7.0
Good
9,210 reviews
Delta
8.0
Very good
7,920 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.9

Comfort

7.9

Overall

8.0

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

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.

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

    Our cheapest airline available from Ottawa to St. Louis is Air Canada. Our recent data shows that you can find tickets from as low as $496 on this airline. Additional options worth looking into are Delta and United Airlines, starting at $532 and $543 round-trip. You may be able to fly from Ottawa to St. Louis for 24% less than the average price by searching for these airlines.

  • Can I find deals for flights from Ottawa to St. Louis that include hotel bookings?

    Yes. In addition to deals on Ottawa to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ottawa to St. Louis?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ottawa to St. Louis.

  • Can I find deals for business class flights from Ottawa to St. Louis?

    Yes. Cheapflights offers flight deals from Ottawa to St. Louis 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 Ottawa to St. Louis?

    Currently, August is the cheapest month in which you can book a flight from Ottawa to St. Louis (average of $311). Flying from Ottawa to St. Louis in March is currently the most expensive (average of $356). 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 Ottawa?

Book flights to Ottawa if you plan to visit one of these locations
Fenton
Maryland Heights
Fairview Heights
Collinsville
Wentzville
Eureka
St. Peters
Festus
Glencoe
Alton
Farmington

Browse thousands of different options on Cheapflights for your next trip

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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 2,558,603 searches. Data last updated April 25, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$637Average$667FlexibilityNo cancel feeOn-time67%

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