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St. Louis

$182+ Cheap flights from Ontario 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 1/6. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — STL
Nov 25 — Dec 21
Mon 11/25
Mon 12/2
1 adult, Economy
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Cheap flight deals from Ontario to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (CAON) 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 November 20, 2024.

Find flight deals from Ontario to St. Louis

Cheapest flights from Ontario to St. Louis
Explore the most affordable flight options available from Ontario to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 20, 2024.

This Kiwi.com deal was found by Cheapflights users on 11/20. 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.
Mon 12/93:55 pmYUL - STL
1 stop24h 26mMultiple Airlines
Mon 12/168:34 pmSTL - YUL
1 stop19h 01mMultiple Airlines
Deal found 11/20$333
This Mytrip deal was found by Cheapflights users on 11/20. 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 12/1312:20 pmYYZ - STL
2 stops24h 25mMultiple Airlines
Mon 12/165:00 pmSTL - YYZ
3 stops28h 35mMultiple Airlines
Deal found 11/20$464
This Delta deal was found by Cheapflights users on 11/19. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/136:15 pmYYZ - STL
1 stop6h 28mDelta
Mon 12/163:40 pmSTL - YYZ
1 stop6h 10mDelta
Deal found 11/19$479
This Air Canada deal was found by Cheapflights users on 11/19. 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 12/129:00 amYYZ - STL
1 stop7h 34mAir Canada
Sun 12/155:40 pmSTL - YYZ
1 stop5h 19mAir Canada
Deal found 11/19$481
This American Airlines deal was found by Cheapflights users on 11/19. 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 12/136:15 amYYZ - STL
1 stop4h 30mAmerican Airlines
Fri 12/205:03 amSTL - YYZ
1 stop9h 42mAmerican Airlines
Deal found 11/19$490
This United Airlines deal was found by Cheapflights users on 11/19. 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.
Thu 12/127:20 amYYZ - STL
2 stops9h 14mUnited Airlines
Sun 12/155:40 pmSTL - YYZ
1 stop5h 19mUnited Airlines
Deal found 11/19$493
This American Airlines deal was found by Cheapflights users on 11/20. 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.
Mon 12/97:14 amYUL - STL
1 stop17h 45mAmerican Airlines
Mon 12/1611:00 amSTL - YUL
2 stops10h 57mAmerican Airlines
Deal found 11/20$539
This Expedia deal was found by Cheapflights users on 11/19. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/179:30 amYYZ - STL
2 stops13h 56mWestJet
Tue 12/245:17 pmSTL - YYZ
1 stop5h 36mWestJet
Deal found 11/19$571
This United Airlines deal was found by Cheapflights users on 11/19. 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.
Tue 12/249:15 amYUL - STL
1 stop6h 09mUnited Airlines
Thu 1/27:00 amSTL - YUL
1 stop7h 58mUnited Airlines
Deal found 11/19$621
This Justfly.com deal was found by Cheapflights users on 11/20. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/166:00 amYUL - STL
1 stop5h 40mWestJet
Mon 12/235:17 pmSTL - YUL
2 stops30h 23mWestJet
Deal found 11/20$632
This United Airlines deal was found by Cheapflights users on 11/20. 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 12/1811:25 amYOW - STL
1 stop11h 11mUnited Airlines
Wed 12/258:00 amSTL - YOW
2 stops13h 01mUnited Airlines
Deal found 11/20$652
This Delta deal was found by Cheapflights users on 11/19. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/296:05 amYUL - STL
2 stops11h 28mDelta
Sun 12/11:50 pmSTL - YUL
1 stop8h 21mDelta
Deal found 11/19$774

Find flights from Ontario to St. Louis within your budget

Customize your flight search to find flights from Ontario 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 2,629,791 searches. Data last updated November 20, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Mon 12/9

3:55 pm-3:21 pm

1 stop24h 26m

Lambert-St Louis

Mon 12/16

8:34 pm-4:35 pm

1 stop19h 01m

$333

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Mon 1/6

4:10 pm-11:40 pm

1 stop8h 30m

Lambert-St Louis

Sun 1/12

8:12 am-8:17 pm

1 stop11h 05m

$453

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Mon 1/13

2:00 pm-2:43 pm

3 stops25h 43m

Lambert-St Louis

Wed 1/15

12:00 pm-11:53 pm

3 stops34h 53m

$464

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Mon 2/17

4:10 pm-2:25 pm

1 stop23h 15m

Lambert-St Louis

Wed 2/19

7:00 am-2:55 pm

1 stop30h 55m

$472

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Fri 1/17

1:14 pm-10:09 pm

1 stop9h 55m

Lambert-St Louis

Mon 1/20

5:40 am-5:35 pm

1 stop10h 55m

$473

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Fri 1/17

6:46 pm-12:31 pm

1 stop18h 45m

Lambert-St Louis

Tue 1/21

10:20 am-8:31 pm

1 stop9h 11m

$478

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Fri 12/13

6:15 pm-11:43 pm

1 stop6h 28m

Lambert-St Louis

Mon 12/16

3:40 pm-10:50 pm

1 stop6h 10m

$479

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Thu 12/12

9:00 am-3:34 pm

1 stop7h 34m

Lambert-St Louis

Sun 12/15

5:40 pm-11:59 pm

1 stop5h 19m

$481

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

Sat 2/1

6:00 am-10:54 am

1 stop5h 54m

Lambert-St Louis

Sun 2/23

1:03 pm-6:47 pm

1 stop4h 44m

$486

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

Thu 12/12

7:20 am-3:34 pm

2 stops9h 14m

Lambert-St Louis

Sun 12/15

5:40 pm-11:59 pm

1 stop5h 19m

$493

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/19

Showing 1-10 of 25 results
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Best time to book a flight from Ontario to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Ontario 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 Ontario to St. Louis

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

What is the cheapest month to book a flight from Region of Ontario to St. Louis?

Currently, September is the cheapest month in which you can book a flight from Region of Ontario to St. Louis (average of $308). Flying from Region of Ontario to St. Louis in March is currently the most expensive (average of $357). 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.

What is the cheapest time of day to fly from ON to STL?

Find hourly flight availability from Ontario to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 20, 2024.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Region of Ontario to St. Louis as you normally would.

Weekly flight availability from Region of Ontario to St. Louis

Explore weekly flight availability from Ontario to St. Louis. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated November 20, 2024.

The most flights from CAON to STL are scheduled on a Monday (2 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (1 on average).

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 November 20, 2024.
Peruse reviews from past customers who have flown with Alaska Airlines, Delta and Air Canada from Ontario to St. Louis to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,461 reviews

Entertainment

7.1

Comfort

7.9

Food

7.2

Overall

8.0

Crew

8.5

Boarding

8.2

Reviews

1 / 10

Service was good. We pre-ordered a snack but never made it to us.

Alaska Airlines
8.0
Very good
9,461 reviews
Alaska Airlines
8.0
Very good
9,461 reviews

Entertainment

7.1

Comfort

7.9

Food

7.2

Overall

8.0

Crew

8.5

Boarding

8.2

Reviews

1 / 10

Service was good. We pre-ordered a snack but never made it to us.

Delta
8.0
Very good
8,756 reviews
Alaska Airlines
8.0
Very good
9,461 reviews

Entertainment

7.1

Comfort

7.9

Food

7.2

Overall

8.0

Crew

8.5

Boarding

8.2

Reviews

1 / 10

Service was good. We pre-ordered a snack but never made it to us.

United Airlines
7.4
Good
9,171 reviews
Alaska Airlines
8.0
Very good
9,461 reviews

Entertainment

7.1

Comfort

7.9

Food

7.2

Overall

8.0

Crew

8.5

Boarding

8.2

Reviews

1 / 10

Service was good. We pre-ordered a snack but never made it to us.

WestJet
7.3
Good
2,811 reviews
Alaska Airlines
8.0
Very good
9,461 reviews

Entertainment

7.1

Comfort

7.9

Food

7.2

Overall

8.0

Crew

8.5

Boarding

8.2

Reviews

1 / 10

Service was good. We pre-ordered a snack but never made it to us.

American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
9,461 reviews

Entertainment

7.1

Comfort

7.9

Food

7.2

Overall

8.0

Crew

8.5

Boarding

8.2

Reviews

1 / 10

Service was good. We pre-ordered a snack but never made it to us.

Related info for your journey

Find useful and relevant information for your journey from Ontario 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 airport do you fly into for flights to St. Louis from Ontario?

    Located just 12.7 mi from the city center, Lambert-St Louis (STL) is the airport most travelers will use when flying to St. Louis from Ontario.

  • What are the cheapest airlines to fly from Region of Ontario to St. Louis one-way?

    $225 is the cheapest one-way deal found within the past few days, from Air Canada. You may also be able to find cheap deals on American Airlines and United Airlines, with prices starting from $266 and $282, respectively.

  • What are the most popular routes from Region of Ontario to St. Louis?

    While some choose either Montreal Pierre Elliott Trudeau Intl - Lambert-St Louis or Ottawa - Lambert-St Louis, Toronto Pearson Intl - Lambert-St Louis is the most popular route from Region of Ontario to St. Louis.

  • What are the most reliable airlines from Region of Ontario to St. Louis?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Region of Ontario to St. Louis on time: Air Canada (82%), Jazz (82%), United Airlines (80%).

  • What are the cheapest flights from Region of Ontario to St. Louis?

    The cheapest flight price from Region of Ontario to St. Louis is $185. On average you can expect to pay $382. The most popular route, (Toronto Pearson Intl - Lambert-St Louis), can usually be booked for $258.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Ontario 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 Region of Ontario to St. Louis?

    Currently, September is the cheapest month in which you can book a flight from Region of Ontario to St. Louis (average of $308). Flying from Region of Ontario to St. Louis in March is currently the most expensive (average of $357). 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.

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Alternative routes for Ontario to St. Louis

See prices for flight routes from nearby airports that may be better suited for you.
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Top 2 airlines flying from Ontario to St. Louis

Discover the top 2 airlines that operate flights from Ontario 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 2,629,791 searches. Data last updated November 20, 2024.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$264Average$549FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$575Average$730FlexibilityNo cancel feeOn-time69%
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