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Cheap flights from Ottawa to St. Louis from C$ 725

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 21/3. Fares are subject to change and may not be available on all flights or dates of travel.
YOW — STL
25 Feb — 4 Mar1
1 adult

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 20 February 2025.

Round-trip from

C$ 725

Popular in

August

Cheapest in

September

Average price

C$ 916
Air Canada
  • Air Canada
  • 21/3-24/3
  • 2 total stops
  • 10h 07m total
  • Ottawa to St. Louis
Search Deals
Highest demand for flights based on searches. 0% potential increase in price (C$ 4 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease (C$ 19 potential savings vs. average RT price).
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Average for round-trip flights in February 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 20 February 2025.

Fri 21/311:25 a.m.YOW - STL
1 stop5h 06mAir Canada
Mon 24/311:05 a.m.STL - YOW
1 stop5h 01mAir Canada
Deal found 19/2C$ 725
Sat 5/44:20 p.m.YOW - STL
1 stop26h 32mMultiple Airlines
Sat 12/412:15 p.m.STL - YOW
3 stops30h 57mMultiple Airlines
Deal found 19/2C$ 777
Fri 21/36:00 a.m.YOW - STL
2 stops10h 31mUnited Airlines
Mon 24/310:03 a.m.STL - YOW
2 stops10h 58mUnited Airlines
Deal found 19/2C$ 864

Find flights from Ottawa to St. Louis within your budget

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 629,999 searches. Data last updated 20 February 2025.

Fly from

Ottawa

Fly to

St. Louis

Route

Depart

Return

Price

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Fri 21/3

11:25 a.m.-3:31 p.m.

1 stop5h 06m

Lambert-St Louis

Mon 24/3

11:05 a.m.-5:06 p.m.

1 stop5h 01m

C$ 725

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Sat 5/4

4:20 p.m.-5:52 p.m.

1 stop26h 32m

Lambert-St Louis

Sat 12/4

12:15 p.m.-8:12 p.m.

3 stops30h 57m

C$ 777

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Fri 21/3

6:00 a.m.-3:31 p.m.

2 stops10h 31m

Lambert-St Louis

Mon 24/3

10:03 a.m.-10:01 p.m.

2 stops10h 58m

C$ 864

Flights are sorted by cheapest round-trip flights first.

Deals found on 19/2

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.

Travel insights for flights from Ottawa to St. Louis

Get recent, data-driven insights about flights from Ottawa to St. Louis including ideal travel times, pricing trends, and more.

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

Currently, January is the cheapest month in which you can book a flight from Ottawa to St. Louis (average of C$ 365). Flying from Ottawa to St. Louis in September is currently the most expensive (average of C$ 491). 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 56.0 - 119.0 mm per month. May is typically the wettest month, when rainfall can reach 119.0 mm. February is typically the driest time to visit St. Louis when rainfall is around 56.0 mm.

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 27.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 0.0 C).

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 20 February 2025.
United Airlines
7.4
Good
8,771 reviews
Check prices

Entertainment

7.1

Boarding

7.7

Comfort

7.3

Food

6.7

Crew

8.1

Overall

7.4

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

United Airlines
7.4
Good
8,771 reviews
United Airlines
7.4
Good
8,771 reviews
Check prices

Entertainment

7.1

Boarding

7.7

Comfort

7.3

Food

6.7

Crew

8.1

Overall

7.4

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

Air Canada
7.0
Good
8,748 reviews
United Airlines
7.4
Good
8,771 reviews
Check prices

Entertainment

7.1

Boarding

7.7

Comfort

7.3

Food

6.7

Crew

8.1

Overall

7.4

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

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?

    Air Canada, at C$ 725, was found to be the cheapest airline from Ottawa to St. Louis. An alternate airline flying to your destination would be United Airlines. Air Canada is currently priced 23% below the average price you’ll pay for this route.

  • 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, January is the cheapest month in which you can book a flight from Ottawa to St. Louis (average of C$ 365). Flying from Ottawa to St. Louis in September is currently the most expensive (average of C$ 491). 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

Travelling to a place near Ottawa?

Book flights to Ottawa if you plan to visit one of these locations
St. Peters
Chesterfield

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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 629,999 searches. Data last updated 20 February 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapestC$ 781AverageC$ 901FlexibilityNo cancel feeOn-time67%
Search Air Canada flights

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How does Cheapflights help users find flights from Ottawa to St. Louis?

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Why should you use Cheapflights to find cheap flight tickets from Ottawa to St. Louis?

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Can Cheapflights notify me if prices for flights from Ottawa to St. Louis become cheaper?

Yes! Start tracking prices for Ottawa to St. Louis flights today and get alerted whenever prices for these flights change. To access this feature, click the bell icon next to the flight deals above, which will prompt you for a valid email address to receive your alerts.

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