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

For one-way options, check prices for Delta. According to our data, you can fly for as low as C$ 273. Users have also found prices from C$ 314 and C$ 384 on American Airlines and Alaska Airlines, respectively.

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

The most popular flight routes from St. Louis to Region of Ontario are Lambert-St Louis - Toronto Pearson Intl, Lambert-St Louis - Montreal Pierre Elliott Trudeau Intl and Lambert-St Louis - London.

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

The cheapest flight price from St. Louis to Region of Ontario is C$ 392. On average you can expect to pay C$ 535. The most popular route, (Lambert-St Louis - Toronto Pearson Intl), can usually be booked for C$ 514.

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

Before booking your flight to Region of Ontario from St. Louis, check out the most reliable airlines to get you to your destination on time: Air Canada (74%), Jazz (74%), United Airlines( 74%).

How far in advance should I book a flight from St. Louis to Region of Ontario?

When searching for a good deal, it’s best to be prepared for potential fluctuations in price. We recommend booking at least 53 days in advance, which can save you up to 233% on flights from St. Louis to Region of Ontario compared to booking the week you need them. Waiting 53 days out may not be for everyone, so we have options available for flights within the next two weeks, with the lowest price starting at C$ 462. For sooner than that we have options available in the next 3 days from C$ 681.

What is the cheapest month to fly from St. Louis to Region of Ontario?

March is one of the best times of the year to fly to Region of Ontario from St. Louis. Prices for March average C$ 562 per person but you can even find prices for as low as C$ 253. The most expensive prices can be found in the month of February. Opting for a March flight can save you 67% on your journey compared to booking in February

What airport do you fly from for flights from St. Louis to Ontario?

If you book a flight to Ontario from St. Louis, you will be flying from Lambert-St Louis, which is the city’s only airport. Lambert-St Louis (STL) is located 20.4 km from the centre of St. Louis.

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

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

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

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

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

Yes. Cheapflights offers flight deals from St. Louis to Ontario by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

C$ 235+ Flights from St. Louis to Ontario

Cheap flight deals from St. Louis to Ontario

Round-trip from	C$ 432
One-way from	C$ 235
Good one-way deal	C$ 408 or less

18/2-25/2
3 total stops
29h 32m total
St. Louis to Ontario

Search Deals

28/1
2 total stops
28h 53m total
St. Louis to Ontario

Search Deals

Price to beat on a one-way flight from Lambert-St Louis to Ontario.

Search Deals

Find flight deals from St. Louis to Ontario

Cheapest flights from St. Louis to Ontario
Explore the most affordable flight options available from St. Louis to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 21 January 2025.

Tue 18/24:00 p.m.STL - YYZ

2 stops20h 55mMultiple Airlines

Tue 25/27:05 a.m.YYZ - STL

1 stop8h 37mMultiple Airlines

Deal found 21/1C$ 432

Thu 27/21:35 p.m.STL - YYZ

1 stop9h 04mDelta

Wed 5/37:55 a.m.YYZ - STL

1 stop9h 54mDelta

Deal found 21/1C$ 625

Tue 11/25:40 a.m.STL - YYZ

1 stop10h 55mAmerican Airlines

Thu 13/211:31 a.m.YYZ - STL

1 stop11h 32mAmerican Airlines

Deal found 21/1C$ 651

Fri 14/25:15 p.m.STL - YUL

3 stops24h 00mMultiple Airlines

Sun 16/26:50 a.m.YUL - STL

3 stops29h 40mMultiple Airlines

Deal found 20/1C$ 669

Wed 5/36:06 a.m.STL - YUL

1 stop9h 13mDelta

Wed 12/36:00 a.m.YUL - STL

1 stop9h 49mDelta

Deal found 21/1C$ 689

Tue 11/26:00 a.m.STL - YYZ

2 stops29h 37mWestJet

Thu 13/27:55 a.m.YYZ - STL

1 stop14h 07mWestJet

Deal found 21/1C$ 714

Tue 4/37:00 a.m.STL - YYZ

1 stop30h 55mAlaska Airlines

Tue 11/34:20 p.m.YYZ - STL

1 stop32h 39mAlaska Airlines

Deal found 21/1C$ 728

Wed 19/24:58 p.m.STL - YUL

1 stop16h 07mAmerican Airlines

Wed 26/25:35 p.m.YUL - STL

1 stop18h 59mAmerican Airlines

Deal found 21/1C$ 750

Fri 7/31:05 p.m.STL - YYZ

1 stop5h 40mAir Canada

Fri 14/31:50 p.m.YYZ - STL

Nonstop2h 16mAir Canada

Deal found 20/1C$ 802

Mon 31/35:35 p.m.STL - YYZ

1 stop15h 23mUnited Airlines

Thu 10/41:25 p.m.YYZ - STL

2 stops27h 22mUnited Airlines

Deal found 21/1C$ 842

Fri 14/25:50 p.m.STL - YUL

1 stop4h 32mWestJet

Sun 16/26:00 a.m.YUL - STL

1 stop7h 28mWestJet

Deal found 20/1C$ 882

Wed 19/33:50 p.m.STL - YUL

1 stop6h 58mAir Canada

Sat 22/38:50 a.m.YUL - STL

2 stops7h 41mAir Canada

Deal found 21/1C$ 1,065

Best flights from St. Louis to Ontario
Discover carefully curated flight deals from St. Louis to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated 21 January 2025.

Tue 18/24:00 p.m.STL - YYZ

2 stops20h 55mMultiple Airlines

Tue 25/27:05 a.m.YYZ - STL

1 stop8h 37mMultiple Airlines

Deal found 21/1C$ 432

Thu 27/21:35 p.m.STL - YYZ

1 stop9h 04mDelta

Wed 5/37:55 a.m.YYZ - STL

1 stop9h 54mDelta

Deal found 21/1C$ 625

Tue 11/25:40 a.m.STL - YYZ

1 stop10h 55mAmerican Airlines

Thu 13/211:31 a.m.YYZ - STL

1 stop11h 32mAmerican Airlines

Deal found 21/1C$ 651

Tue 11/26:00 a.m.STL - YYZ

2 stops29h 37mWestJet

Thu 13/27:55 a.m.YYZ - STL

1 stop14h 07mWestJet

Deal found 21/1C$ 714

Tue 4/37:00 a.m.STL - YYZ

1 stop30h 55mAlaska Airlines

Tue 11/34:20 p.m.YYZ - STL

1 stop32h 39mAlaska Airlines

Deal found 21/1C$ 728

Fri 7/31:05 p.m.STL - YYZ

1 stop5h 40mAir Canada

Fri 14/31:50 p.m.YYZ - STL

Nonstop2h 16mAir Canada

Deal found 20/1C$ 802

Mon 31/35:35 p.m.STL - YYZ

1 stop15h 23mUnited Airlines

Thu 10/41:25 p.m.YYZ - STL

2 stops27h 22mUnited Airlines

Deal found 21/1C$ 842

Fri 14/25:15 p.m.STL - YUL

3 stops24h 00mMultiple Airlines

Sun 16/26:50 a.m.YUL - STL

3 stops29h 40mMultiple Airlines

Deal found 20/1C$ 669

Wed 5/36:06 a.m.STL - YUL

1 stop9h 13mDelta

Wed 12/36:00 a.m.YUL - STL

1 stop9h 49mDelta

Deal found 21/1C$ 689

Wed 19/24:58 p.m.STL - YUL

1 stop16h 07mAmerican Airlines

Wed 26/25:35 p.m.YUL - STL

1 stop18h 59mAmerican Airlines

Deal found 21/1C$ 750

Fri 14/25:50 p.m.STL - YUL

1 stop4h 32mWestJet

Sun 16/26:00 a.m.YUL - STL

1 stop7h 28mWestJet

Deal found 20/1C$ 882

Wed 19/33:50 p.m.STL - YUL

1 stop6h 58mAir Canada

Sat 22/38:50 a.m.YUL - STL

2 stops7h 41mAir Canada

Deal found 21/1C$ 1,065

Direct flights from St. Louis to Ontario
Explore direct flight options from St. Louis to Ontario based on user searches, and compare prices and availability for your desired travel dates. Data last updated 21 January 2025.

Tue 11/23:50 p.m.STL - YYZ

Nonstop1h 55mUnited Airlines

Thu 13/21:50 p.m.YYZ - STL

Nonstop2h 16mUnited Airlines

Deal found 21/1C$ 923

Thu 27/23:50 p.m.STL - YYZ

Nonstop1h 55mAir Canada

Wed 5/31:50 p.m.YYZ - STL

Nonstop2h 16mAir Canada

Deal found 21/1C$ 1,079

Sun 1/61:30 p.m.STL - YUL

Nonstop2h 30mUnited Airlines

Fri 6/66:10 p.m.YUL - STL

Nonstop2h 51mUnited Airlines

Deal found 21/1C$ 1,121

Mon 19/59:15 a.m.STL - YYZ

Nonstop2h 00mMultiple Airlines

Wed 21/56:30 p.m.YYZ - STL

Nonstop2h 13mMultiple Airlines

Deal found 21/1C$ 1,228

Sun 1/61:30 p.m.STL - YUL

Nonstop2h 30mAir Canada

Sun 8/66:10 p.m.YUL - STL

Nonstop2h 51mAir Canada

Deal found 21/1C$ 1,285

Last-minute flights from St. Louis to Ontario
Discover last-minute flight deals from St. Louis to Ontario. Data last updated 21 January 2025 and is based on user searches.

Sun 26/14:28 p.m.STL - YYZ

1 stop18h 14mMultiple Airlines

Thu 30/17:05 a.m.YYZ - STL

1 stop8h 38mMultiple Airlines

Deal found 21/1C$ 574

Tue 28/15:50 p.m.STL - YUL

1 stop4h 35mDelta

Tue 4/211:20 a.m.YUL - STL

1 stop10h 42mDelta

Deal found 20/1C$ 964

Tue 28/16:29 p.m.STL - YUL

2 stops14h 41mAmerican Airlines

Tue 4/210:54 a.m.YUL - STL

2 stops9h 29mAmerican Airlines

Deal found 20/1C$ 1,028

Wed 29/11:00 p.m.STL - YYZ

1 stop7h 32mAmerican Airlines

Fri 28/21:14 p.m.YYZ - STL

1 stop9h 49mAmerican Airlines

Deal found 21/1C$ 902

Wed 29/16:43 a.m.STL - YYZ

2 stops8h 28mDelta

Fri 28/27:55 a.m.YYZ - STL

2 stops9h 42mDelta

Deal found 21/1C$ 1,305

Wed 29/13:50 p.m.STL - YYZ

Nonstop1h 55mAir Canada

Fri 28/21:50 p.m.YYZ - STL

Nonstop2h 16mAir Canada

Deal found 21/1C$ 1,323

Wed 29/111:30 a.m.STL - YYZ

1 stop4h 16mUnited Airlines

Fri 28/21:50 p.m.YYZ - STL

Nonstop2h 16mUnited Airlines

Deal found 21/1C$ 1,330

Tue 11/25:40 a.m.STL - YYZ

1 stop10h 55mAmerican Airlines

Thu 13/211:31 a.m.YYZ - STL

1 stop11h 32mAmerican Airlines

Deal found 21/1C$ 651

Tue 11/26:00 a.m.STL - YYZ

2 stops29h 37mWestJet

Thu 13/27:55 a.m.YYZ - STL

1 stop14h 07mWestJet

Deal found 21/1C$ 714

Tue 11/23:50 p.m.STL - YYZ

Nonstop1h 55mUnited Airlines

Thu 13/21:50 p.m.YYZ - STL

Nonstop2h 16mUnited Airlines

Deal found 21/1C$ 923

Tue 11/26:03 a.m.STL - YYZ

2 stops31h 52mAlaska Airlines

Thu 13/24:20 p.m.YYZ - STL

2 stops17h 24mAlaska Airlines

Deal found 21/1C$ 1,102

Fri 14/25:15 p.m.STL - YUL

3 stops24h 00mMultiple Airlines

Sun 16/26:50 a.m.YUL - STL

3 stops29h 40mMultiple Airlines

Deal found 20/1C$ 669

One-way flights from St. Louis to Ontario
Search for one-way flight options from St. Louis to Ontario. Find affordable one-way fares based on user searches. Data last updated 21 January 2025.

Tue 28/13:48 p.m.STL - YYZ

2 stops28h 53mMultiple Airlines

Deal found 21/1C$ 235

Wed 26/25:20 p.m.STL - YUL

1 stop20h 20mMultiple Airlines

Deal found 20/1C$ 250

Wed 12/21:35 p.m.STL - YYZ

1 stop9h 04mDelta

Deal found 21/1C$ 273

Wed 12/25:40 a.m.STL - YYZ

2 stops10h 44mAmerican Airlines

Deal found 21/1C$ 314

Fri 21/27:00 a.m.STL - YYZ

1 stop30h 55mAlaska Airlines

Deal found 20/1C$ 384

Wed 12/28:00 a.m.STL - YYZ

2 stops11h 25mUnited Airlines

Deal found 20/1C$ 393

Fri 7/33:50 p.m.STL - YYZ

Nonstop1h 55mAir Canada

Deal found 21/1C$ 406

Fri 7/36:00 a.m.STL - YYZ

2 stops16h 30mWestJet

Deal found 21/1C$ 476

Fri 13/61:30 p.m.STL - YUL

Nonstop2h 30mUnited Airlines

Deal found 21/1C$ 524

Fri 13/62:18 p.m.STL - YUL

1 stop7h 51mDelta

Deal found 21/1C$ 530

Sat 29/31:57 p.m.STL - YYZ

1 stop19h 08mBritish Airways

Deal found 21/1C$ 586

Fri 13/66:30 a.m.STL - YUL

2 stops32h 57mWestJet

Deal found 21/1C$ 629

Find flights from St. Louis to Ontario within your budget

Fly from

Fly to

Route

Depart

Return

Price

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 18/2

4:00 p.m.-1:55 p.m.

2 stops20h 55m

Toronto Pearson Intl

Tue 25/2

7:05 a.m.-2:42 p.m.

1 stop8h 37m

C$ 432

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Thu 27/2

1:35 p.m.-11:39 p.m.

1 stop9h 04m

Toronto Pearson Intl

Wed 5/3

7:55 a.m.-4:49 p.m.

1 stop9h 54m

C$ 625

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 11/2

5:40 a.m.-5:35 p.m.

1 stop10h 55m

Toronto Pearson Intl

Thu 13/2

11:31 a.m.-10:03 p.m.

1 stop11h 32m

C$ 651

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Fri 14/2

5:15 p.m.-6:15 p.m.

3 stops24h 00m

Montreal Pierre Elliott Trudeau Intl

Sun 16/2

6:50 a.m.-11:30 a.m.

3 stops29h 40m

C$ 669

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Wed 5/3

6:06 a.m.-4:19 p.m.

1 stop9h 13m

Montreal Pierre Elliott Trudeau Intl

Wed 12/3

6:00 a.m.-2:49 p.m.

1 stop9h 49m

C$ 689

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 11/2

6:00 a.m.-12:37 p.m.

2 stops29h 37m

Toronto Pearson Intl

Thu 13/2

7:55 a.m.-9:02 p.m.

1 stop14h 07m

C$ 714

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Tue 4/3

7:00 a.m.-2:55 p.m.

1 stop30h 55m

Toronto Pearson Intl

Tue 11/3

4:20 p.m.-11:59 p.m.

1 stop32h 39m

C$ 728

St. LouisMontreal

STL - YUL

STLYUL

Lambert-St Louis

Wed 19/2

4:58 p.m.-10:05 a.m.

1 stop16h 07m

Montreal Pierre Elliott Trudeau Intl

Wed 26/2

5:35 p.m.-11:34 a.m.

1 stop18h 59m

C$ 750

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Fri 7/3

1:05 p.m.-7:45 p.m.

1 stop5h 40m

Toronto Pearson Intl

Fri 14/3

1:50 p.m.-3:06 p.m.

Nonstop2h 16m

C$ 802

St. LouisToronto

STL - YYZ

STLYYZ

Lambert-St Louis

Mon 31/3

5:35 p.m.-9:58 a.m.

1 stop15h 23m

Toronto Pearson Intl

Thu 10/4

1:25 p.m.-3:47 p.m.

2 stops27h 22m

C$ 842

Flights are sorted by cheapest round-trip flights first.

Deals found on 21/1

Showing 1-10 of 25 results

Best time to book a flight from St. Louis to Ontario

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

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

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

Currently, January is the cheapest month in which you can book a flight from St. Louis to Region of Ontario (average of C$ 168). Flying from St. Louis to Region of Ontario in July is currently the most expensive (average of C$ 258). 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 STL to ON?

When flying from St. Louis to Region of Ontario, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Weekly flight availability from St. Louis to Region of Ontario

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

Rainfall in Ontario by month

In terms of precipitation, rainfall in Region of Ontario ranges from 51.0 - 83.0 mm per month. June is typically the wettest month, when rainfall can reach 83.0 mm. February is typically the driest time to visit Region of Ontario when rainfall is around 51.0 mm.

Temperature in Ontario by month

If weather is an important factor for your trip to Region of Ontario, 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 21.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around -6.0 C).

Reviews of airlines servicing Ontario

Read through reviews of airlines operating flights from St. Louis to Ontario, such as American Airlines, WestJet and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Alaska Airlines

8.0

Very good

9,706 reviews

Check prices

Reviews

1 / 10

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Alaska Airlines

8.0

Very good

9,706 reviews

Alaska Airlines

8.0

Very good

9,706 reviews

Check prices

Reviews

1 / 10

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Delta

8.0

Very good

8,521 reviews

Alaska Airlines

8.0

Very good

9,706 reviews

Check prices

Reviews

1 / 10

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

United Airlines

7.4

Good

8,985 reviews

Alaska Airlines

8.0

Very good

9,706 reviews

Check prices

Reviews

1 / 10

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

American Airlines

7.2

Good

10,000 reviews

Alaska Airlines

8.0

Very good

9,706 reviews

Check prices

Reviews

1 / 10

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

WestJet

7.2

Good

2,829 reviews

Alaska Airlines

8.0

Very good

9,706 reviews

Check prices

Reviews

1 / 10

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Related info for your journey

What airport do you fly from for flights from St. Louis to Ontario?
If you book a flight to Ontario from St. Louis, you will be flying from Lambert-St Louis, which is the city’s only airport. Lambert-St Louis (STL) is located 20.4 km from the centre of St. Louis.
What are the cheapest airlines to fly from St. Louis to Region of Ontario one-way?
For one-way options, check prices for Delta. According to our data, you can fly for as low as C$ 273. Users have also found prices from C$ 314 and C$ 384 on American Airlines and Alaska Airlines, respectively.
What are the most popular routes from St. Louis to Region of Ontario?
The most popular flight routes from St. Louis to Region of Ontario are Lambert-St Louis - Toronto Pearson Intl, Lambert-St Louis - Montreal Pierre Elliott Trudeau Intl and Lambert-St Louis - London.
What are the most reliable airlines from St. Louis to Region of Ontario?
Before booking your flight to Region of Ontario from St. Louis, check out the most reliable airlines to get you to your destination on time: Air Canada (74%), Jazz (74%), United Airlines( 74%).
What are the cheapest flights from St. Louis to Region of Ontario?
The cheapest flight price from St. Louis to Region of Ontario is C$ 392. On average you can expect to pay C$ 535. The most popular route, (Lambert-St Louis - Toronto Pearson Intl), can usually be booked for C$ 514.
Can I find deals for flights from St. Louis to Ontario that include hotel bookings?
Yes. In addition to deals on St. Louis to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from St. Louis to Ontario?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Ontario.
Can I find deals for business class flights from St. Louis to Ontario?
Yes. Cheapflights offers flight deals from St. Louis to Ontario 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 St. Louis to Region of Ontario?
Currently, January is the cheapest month in which you can book a flight from St. Louis to Region of Ontario (average of C$ 168). Flying from St. Louis to Region of Ontario in July is currently the most expensive (average of C$ 258). 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

Browse thousands of different options on Cheapflights for your next trip

Alternative routes for St. Louis to Ontario

Complete your trip

Region of Ontario car rentals

Toronto Pearson Intl Airport car rentals

Ottawa Airport car rentals

Toronto Island Airport car rentals

Hamilton Airport car rentals

London Airport car rentals

Toronto Region of Waterloo Intl Airport car rentals

Thunder Bay Airport car rentals

Sault Ste Marie Airport car rentals

Kingston Airport car rentals

Timmins Airport car rentals

North Bay Airport car rentals

Direct flights to Canada

Top airline flying from St. Louis to Ontario

Airline	Cheapest	Average	Flexibility	On-time
Air Canada	CheapestC$ 371	AverageC$ 803	FlexibilityNo cancel fee	On-time67%	Search Air Canada flights

Fly with Cheapflights

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

Cheapflights helps you search for flights from St. Louis to Ontario via 900+ travel sites so you don’t have to. After performing a flight search, users can also filter their flight selection by filtering for price, number of stops, airlines, and so on.

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

By finding flights from multiple airlines and providers at completely no cost, Cheapflights helps millions of users like you annually find the best flights to Ontario from St. Louis.

Can Cheapflights find flights from St. Louis to Ontario with no change fees?

Certainly. Search results for flights to Ontario from St. Louis shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

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

Yes! Start tracking prices for St. Louis to Ontario 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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Cheap flights from St. Louis to Ontario from C$ 235

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 28/1. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from St. Louis to Ontario

Round-trip from

One-way from

Good one-way deal

Find flight deals from St. Louis to Ontario

Cheapest flights from St. Louis to OntarioExplore the most affordable flight options available from St. Louis to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 21 January 2025.

Explore the most affordable flight options available from St. Louis to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 21 January 2025.

Find flights from St. Louis to Ontario within your budget

Best time to book a flight from St. Louis to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from St. Louis with our price prediction graph.

Travel insights for flights from St. Louis to Ontario

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

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

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

Find hourly flight availability from St. Louis to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 21 January 2025.

Weekly flight availability from St. Louis to Region of Ontario

Explore weekly flight availability from St. Louis to Ontario. 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 21 January 2025.

Rainfall in Ontario by month

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

Temperature in Ontario by month

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

Reviews of airlines servicing Ontario

Read through reviews of airlines operating flights from St. Louis to Ontario, such as American Airlines, WestJet and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Ontario. 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 from for flights from St. Louis to Ontario?

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

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

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

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

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

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

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

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Cheapest flights from St. Louis to Ontario
Explore the most affordable flight options available from St. Louis to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 21 January 2025.