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St. Louis

$146+ 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 1/7. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — STL
dic. 23 — dic. 301
lun. 12/23
lun. 12/30
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 diciembre 18, 2024.

Round-trip from

$367
(Kiwi.com)

One-way from

$146
(Kiwi.com)
From Ontario to Lambert-St Louis
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One-way flight from Ontario to Lambert-St Louis
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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 diciembre 18, 2024.

This Kiwi.com deal was found by Cheapflights users on 12/17. 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.
mar. 12/178:15 pmYYZ - STL
1 stop15h 29mMultiple Airlines
jue. 1/168:31 pmSTL - YYZ
2 stops16h 24mMultiple Airlines
Deal found 12/17$555
This American Airlines deal was found by Cheapflights users on 12/17. 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.
mar. 12/247:30 amYUL - STL
1 stop5h 41mAmerican Airlines
jue. 1/25:03 amSTL - YUL
1 stop7h 32mAmerican Airlines
Deal found 12/17$637
This Kiwi.com deal was found by Cheapflights users on 12/17. 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.
jue. 12/1910:00 amYUL - STL
2 stops14h 28mMultiple Airlines
mié. 12/253:53 pmSTL - YUL
1 stop21h 47mMultiple Airlines
Deal found 12/17$712
This Justfly.com deal was found by Cheapflights users on 12/17. 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.
mar. 12/241:30 pmYUL - STL
2 stops27h 42mWestJet
jue. 1/25:55 pmSTL - YUL
1 stop17h 00mWestJet
Deal found 12/17$746
This American Airlines deal was found by Cheapflights users on 12/17. 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.
dom. 12/2211:50 amYYZ - STL
1 stop8h 10mAmerican Airlines
dom. 12/295:36 amSTL - YYZ
1 stop11h 04mAmerican Airlines
Deal found 12/17$898
This WestJet deal was found by Cheapflights users on 12/16. 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 WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 12/2210:00 amYYZ - STL
2 stops13h 06mWestJet
dom. 12/295:55 pmSTL - YYZ
1 stop3h 46mWestJet
Deal found 12/16$938
This Delta deal was found by Cheapflights users on 12/17. 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.
dom. 12/2210:05 amYYZ - STL
2 stops8h 25mDelta
dom. 12/296:29 amSTL - YYZ
1 stop3h 53mDelta
Deal found 12/17$1,138
This Air Canada deal was found by Cheapflights users on 12/17. 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.
dom. 12/2211:00 amYYZ - STL
1 stop7h 51mAir Canada
dom. 12/293:50 pmSTL - YYZ
Nonstop1h 55mAir Canada
Deal found 12/17$1,257
This United Airlines deal was found by Cheapflights users on 12/17. 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.
dom. 12/221:50 pmYYZ - STL
Nonstop2h 16mUnited Airlines
dom. 12/293:50 pmSTL - YYZ
Nonstop1h 55mUnited Airlines
Deal found 12/17$1,561
This Alaska Airlines deal was found by Cheapflights users on 12/16. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 12/224:22 pmYYZ - STL
2 stops17h 30mAlaska Airlines
dom. 12/297:24 amSTL - YYZ
2 stops30h 43mAlaska Airlines
Deal found 12/16$1,827

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 2,558,603 searches. Data last updated diciembre 18, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

lun. 2/10

6:15 am-11:41 pm

1 stop18h 26m

Lambert-St Louis

lun. 3/3

11:08 pm-4:35 pm

1 stop16h 27m

$367

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

jue. 1/9

2:55 pm-7:55 pm

3 stops30h 00m

Lambert-St Louis

dom. 1/12

4:28 pm-1:55 pm

2 stops20h 27m

$412

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

lun. 1/13

5:15 pm-8:58 am

1 stop16h 43m

Lambert-St Louis

jue. 1/23

6:05 am-9:06 pm

1 stop14h 01m

$431

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

jue. 1/16

1:14 pm-10:09 pm

1 stop9h 55m

Lambert-St Louis

mié. 1/22

12:00 pm-9:20 pm

1 stop8h 20m

$441

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

mié. 2/26

7:55 am-4:49 pm

1 stop9h 54m

Lambert-St Louis

mar. 3/4

6:06 am-4:08 pm

1 stop9h 02m

$450

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

mié. 1/15

7:30 am-12:57 pm

1 stop6h 27m

Lambert-St Louis

vie. 1/17

5:03 pm-10:10 am

1 stop16h 07m

$466

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

jue. 1/16

1:50 pm-3:06 pm

Nonstop2h 16m

Lambert-St Louis

mié. 1/22

3:50 pm-6:45 pm

Nonstop1h 55m

$474

TorontoSt. Louis

YYZ - STL

YYZSTL

Toronto Pearson Intl

jue. 1/16

1:50 pm-3:06 pm

Nonstop2h 16m

Lambert-St Louis

mié. 1/22

3:50 pm-6:45 pm

Nonstop1h 55m

$481

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

lun. 1/13

1:30 pm-11:14 pm

2 stops10h 44m

Lambert-St Louis

jue. 1/23

1:35 pm-9:06 pm

1 stop6h 31m

$509

MontrealSt. Louis

YUL - STL

YULSTL

Montreal Pierre Elliott Trudeau Intl

lun. 2/10

7:00 am-3:38 pm

2 stops9h 38m

Lambert-St Louis

lun. 3/3

10:18 am-7:48 pm

2 stops8h 30m

$535

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/16

Showing 1-10 of 24 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, August is the cheapest month in which you can book a flight from Region of Ontario to St. Louis (average of $311). Flying from Region of Ontario 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.

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 diciembre 18, 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 diciembre 18, 2024.

The most flights from CAON to STL are scheduled on a Monday (2 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (2 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 diciembre 18, 2024.
Peruse reviews from past customers who have flown with Delta, American Airlines 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
9,554 reviews

Entertainment

7.1

Boarding

8.2

Crew

8.5

Comfort

7.9

Food

7.2

Overall

8.0

Reviews

1 / 10

Things were good, crew was good. It was just the flight itself was very rough. Lots of turbulence, probably one of the shakiest flights I've been on. Kids throwing up, kids crying everywhere because of it.

Alaska Airlines
8.0
Very good
9,554 reviews
Alaska Airlines
8.0
Very good
9,554 reviews

Entertainment

7.1

Boarding

8.2

Crew

8.5

Comfort

7.9

Food

7.2

Overall

8.0

Reviews

1 / 10

Things were good, crew was good. It was just the flight itself was very rough. Lots of turbulence, probably one of the shakiest flights I've been on. Kids throwing up, kids crying everywhere because of it.

Delta
8.0
Very good
8,604 reviews
Alaska Airlines
8.0
Very good
9,554 reviews

Entertainment

7.1

Boarding

8.2

Crew

8.5

Comfort

7.9

Food

7.2

Overall

8.0

Reviews

1 / 10

Things were good, crew was good. It was just the flight itself was very rough. Lots of turbulence, probably one of the shakiest flights I've been on. Kids throwing up, kids crying everywhere because of it.

United Airlines
7.4
Good
9,055 reviews
Alaska Airlines
8.0
Very good
9,554 reviews

Entertainment

7.1

Boarding

8.2

Crew

8.5

Comfort

7.9

Food

7.2

Overall

8.0

Reviews

1 / 10

Things were good, crew was good. It was just the flight itself was very rough. Lots of turbulence, probably one of the shakiest flights I've been on. Kids throwing up, kids crying everywhere because of it.

WestJet
7.3
Good
2,818 reviews
Alaska Airlines
8.0
Very good
9,554 reviews

Entertainment

7.1

Boarding

8.2

Crew

8.5

Comfort

7.9

Food

7.2

Overall

8.0

Reviews

1 / 10

Things were good, crew was good. It was just the flight itself was very rough. Lots of turbulence, probably one of the shakiest flights I've been on. Kids throwing up, kids crying everywhere because of it.

American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
9,554 reviews

Entertainment

7.1

Boarding

8.2

Crew

8.5

Comfort

7.9

Food

7.2

Overall

8.0

Reviews

1 / 10

Things were good, crew was good. It was just the flight itself was very rough. Lots of turbulence, probably one of the shakiest flights I've been on. Kids throwing up, kids crying everywhere because of it.

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?

    $261 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 United Airlines and Delta, with prices starting from $265 and $298, 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: United Airlines (91%), Air Canada (91%), Jazz (91%).

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

    The cheapest flight price from Region of Ontario to St. Louis is $218. On average you can expect to pay $304. The most popular route, (Toronto Pearson Intl - Lambert-St Louis), can usually be booked for $283.

  • 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, August is the cheapest month in which you can book a flight from Region of Ontario to St. Louis (average of $311). Flying from Region of Ontario 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.

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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 2,558,603 searches. Data last updated diciembre 18, 2024.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$264Average$558FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$329Average$580FlexibilityNo cancel feeOn-time69%
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