Which airport typically offers the quickest layover for flights from St. Louis to Ontario?

Flights via Phoenix (PHX) offer the fastest connection on this route, with an average layover time of 0h 55m.

What’s the fastest layover option from St. Louis to Ontario?

Flights via Phoenix (PHX) have the shortest average one-way travel time for 1-stop routes: 5h 53m.

What’s the cheapest layover airport for flights from St. Louis to Ontario?

Phoenix (PHX) is the most affordable 1-stop option, with an average round-trip price of $305.

What’s the top layover airport for flights from St. Louis to Ontario?

Phoenix (PHX) – chosen by Cheapflights users on 50% of 1-stop itineraries from St. Louis to Ontario on Cheapflights.

How long is the flight from St. Louis to Ontario?

There are many flights that can get you from St. Louis to Ontario in 6h 02m. Fly via Frontier, Delta, or United Airlines to get the fastest option. The distance between St. Louis and Ontario is about 1541 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

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

Frontier, at $128, was found to be the cheapest airline from St. Louis to Ontario.Alternate airlines to your destination round-trip include Delta and United Airlines. Frontier is priced at 64% lower than the current average price of a flight leaving 3 months from now.

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

The cheapest airline one-way is Frontier, with whom users have recently found tickets for as low as $82. However, be on the lookout for offers from American Airlines and Delta, as they are both options that can get you from St. Louis to Ontario for a low price.

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

What are the most popular airlines that fly from St. Louis to Ontario?

Before booking your flight from St. Louis to Ontario check out the most popular airlines for this route: Frontier, Southwest or American Airlines.

Most accurate provider : When it comes to deals on St. Louis-Ontario flights, users find the pricing of Mytrip to be most consistent on Cheapflights vs. Mytrip Users can find the same prices on St. Louis-Ontario flight deals on Cheapflights vs. Mytrip >95% of the time. Price accuracy is based on data collected from St. Louis-Ontario flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on St. Louis-Ontario flights, Cheapflights users trust Mytrip the most. Mytrip 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 St. Louis-Ontario flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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.

$74+ Flights from St. Louis to Ontario

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1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

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We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

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Cheap 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 December 12, 2025.

Sun 12/2110:10 pmSTL - ONT

1 stop25h 07mFrontier

Sat 12/276:00 amONT - STL

1 stop13h 25mFrontier

Deal found 12/10

$209

Mon 12/2210:10 pmSTL - ONT

1 stop21h 12mFrontier

Mon 12/296:00 pmONT - STL

1 stop25h 25mFrontier

Deal found 12/10

$225

Mon 12/2210:10 pmSTL - ONT

1 stop25h 07mFrontier

Tue 12/306:17 pmONT - STL

1 stop20h 07mFrontier

Deal found 12/10

$226

Mon 12/2210:10 pmSTL - ONT

1 stop21h 12mFrontier

Thu 12/256:00 amONT - STL

1 stop8h 24mFrontier

Deal found 12/10

$229

Tue 12/2310:10 pmSTL - ONT

1 stop25h 07mFrontier

Fri 12/266:45 amONT - STL

1 stop25h 17mFrontier

Deal found 12/10

$235

Wed 12/317:43 pmSTL - ONT

1 stop6h 16mFrontier

Thu 1/1510:18 pmONT - STL

1 stop12h 22mFrontier

Deal found 12/11

$257

Wed 12/247:43 pmSTL - ONT

1 stop6h 16mFrontier

Thu 1/16:45 amONT - STL

1 stop25h 17mFrontier

Deal found 12/11

$259

Tue 12/3010:10 pmSTL - ONT

1 stop21h 05mFrontier

Thu 1/16:45 amONT - STL

1 stop25h 17mFrontier

Deal found 12/10

$279

Wed 12/245:19 pmSTL - ONT

1 stop26h 03mFrontier

Wed 12/316:00 amONT - STL

1 stop8h 24mFrontier

Deal found 12/11

$299

Wed 12/317:43 pmSTL - ONT

1 stop6h 16mFrontier

Sun 1/46:45 amONT - STL

1 stop25h 17mFrontier

Deal found 12/9

$313

Fri 12/121:16 pmSTL - ONT

1 stop10h 01mFrontier

Sat 12/136:15 amONT - STL

1 stop27h 57mFrontier

Deal found 12/10

$334

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 December 12, 2025.

Mon 1/510:10 pmSTL - ONT

1 stop18h 59mFrontier

Sat 1/103:21 pmONT - STL

1 stop18h 18mFrontier

Deal found 12/11

$183

Tue 1/66:00 amSTL - ONT

1 stop7h 31mDelta

Tue 1/131:11 pmONT - STL

1 stop6h 24mDelta

Deal found 12/9

$326

Wed 1/78:45 amSTL - ONT

1 stop6h 02mUnited Airlines

Sat 1/101:24 pmONT - STL

1 stop5h 34mUnited Airlines

Deal found 12/9

$327

Tue 1/202:50 pmSTL - ONT

1 stop26h 18mAlaska Airlines

Tue 1/2711:53 amONT - STL

1 stop24h 01mAlaska Airlines

Deal found 12/11

$344

Thu 1/2910:01 pmSTL - ONT

1 stop17h 31mFrontier

Sun 2/15:21 pmONT - STL

1 stop25h 29mFrontier

Deal found 12/11

$187

Wed 1/76:05 amSTL - ONT

2 stops12h 00mSouthwest

Sat 1/105:30 amONT - STL

2 stops7h 20mSouthwest

Deal found 12/9

$382

Tue 1/139:57 amSTL - ONT

2 stops13h 01mUnited Airlines

Tue 1/205:05 amONT - STL

1 stop6h 11mUnited Airlines

Deal found 12/10

$335

Tue 1/201:00 pmSTL - ONT

1 stop10h 05mDelta

Sun 1/2510:30 pmONT - STL

1 stop8h 23mDelta

Deal found 12/10

$341

Tue 1/202:50 pmSTL - ONT

1 stop26h 18mAlaska Airlines

Sun 1/256:00 amONT - STL

1 stop29h 54mAlaska Airlines

Deal found 12/10

$354

Thu 1/157:00 amSTL - ONT

1 stop7h 16mDelta

Tue 1/2010:30 pmONT - STL

1 stop8h 23mDelta

Deal found 12/11

$343

Mon 12/2210:10 pmSTL - ONT

1 stop21h 12mFrontier

Fri 1/25:54 pmONT - STL

1 stop25h 31mFrontier

Deal found 12/11

$364

Sat 2/212:47 pmSTL - ONT

1 stop10h 45mAlaska Airlines

Tue 2/246:14 amONT - STL

1 stop29h 37mAlaska Airlines

Deal found 12/9

$376

Last-minute flights from St. Louis to Ontario
Discover last-minute flight deals from St. Louis to Ontario. Data last updated December 12, 2025 and is based on user searches.

Sun 12/2110:10 pmSTL - ONT

1 stop25h 07mFrontier

Sat 12/276:00 amONT - STL

1 stop13h 25mFrontier

Deal found 12/10

$209

Mon 12/2210:10 pmSTL - ONT

1 stop21h 12mFrontier

Mon 12/296:00 pmONT - STL

1 stop25h 25mFrontier

Deal found 12/10

$225

Sun 1/410:10 pmSTL - ONT

1 stop21h 05mFrontier

Thu 1/88:14 pmONT - STL

1 stop13h 58mFrontier

Deal found 12/11

$184

Mon 1/510:10 pmSTL - ONT

1 stop18h 59mFrontier

Sat 1/103:21 pmONT - STL

1 stop18h 18mFrontier

Deal found 12/11

$183

Thu 1/83:43 pmSTL - ONT

2 stops31h 40mFrontier

Thu 1/1510:18 pmONT - STL

1 stop12h 22mFrontier

Deal found 12/11

$202

Fri 1/97:43 pmSTL - ONT

1 stop6h 13mFrontier

Wed 1/147:15 amONT - STL

1 stop5h 33mFrontier

Deal found 12/11

$217

Mon 1/127:43 pmSTL - ONT

1 stop6h 13mFrontier

Thu 1/1510:18 pmONT - STL

1 stop12h 22mFrontier

Deal found 12/11

$182

Mon 1/191:35 pmSTL - ONT

1 stop6h 09mFrontier

Mon 1/261:05 pmONT - STL

1 stop5h 45mFrontier

Deal found 12/10

$201

Sat 1/243:46 pmSTL - ONT

1 stop9h 38mFrontier

Sat 1/317:15 amONT - STL

1 stop5h 31mFrontier

Deal found 12/10

$165

Thu 1/2910:01 pmSTL - ONT

1 stop17h 31mFrontier

Sun 2/15:21 pmONT - STL

1 stop25h 29mFrontier

Deal found 12/11

$187

Fri 1/307:39 pmSTL - ONT

1 stop6h 41mFrontier

Sun 2/15:21 pmONT - STL

1 stop25h 29mFrontier

Deal found 12/10

$149

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 December 12, 2025.

Wed 2/185:44 pmSTL - ONT

1 stop5h 33mFrontier

Deal found 12/10

$74

Sun 1/1112:37 pmSTL - ONT

1 stop7h 47mFrontier

Deal found 12/11

$87

Thu 1/15:19 pmSTL - ONT

1 stop5h 58mFrontier

Deal found 12/11

$92

Mon 1/510:10 pmSTL - ONT

1 stop18h 59mFrontier

Deal found 12/11

$96

Fri 1/210:10 pmSTL - ONT

1 stop27h 11mFrontier

Deal found 12/10

$98

Wed 1/148:32 pmSTL - ONT

2 stops29h 27mFrontier

Deal found 12/11

$107

Mon 1/191:35 pmSTL - ONT

1 stop6h 09mFrontier

Deal found 12/11

$110

Mon 12/2210:10 pmSTL - ONT

1 stop21h 12mFrontier

Deal found 12/10

$119

Sun 12/2110:10 pmSTL - ONT

1 stop25h 07mFrontier

Deal found 12/10

$123

Sun 1/181:35 pmSTL - ONT

1 stop6h 09mFrontier

Deal found 12/11

$124

Wed 12/247:43 pmSTL - ONT

1 stop6h 16mFrontier

Deal found 12/11

$139

Find flight deals from St. Louis to Ontario

Most accurate provider	Mytrip 3 stars
Most trusted provider	Mytrip 3 stars
Round-trip from	$149 (CheapOair)
One-way from	$74 (Frontier)
Popular in	March
Cheapest in	November
Average price	$308

Provider with most accurate pricing for Lambert-St Louis-Ontario flight deals.

Search Deals

Provider most trusted by Cheapflights users for Lambert-St Louis-Ontario flights.

Search Deals

From Lambert-St Louis to Ontario

Search Deals

One-way flight from Lambert-St Louis to Ontario

Search Deals

Highest demand for flights based on searches. 19% potential increase in price ($86 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 8% potential price decrease ($28 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in December 2025

Search Deals

Fly from

Fly to

Route

Depart

Return

Price

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Mon 1/5

10:10 pm-3:09 pm

1 stop18h 59m

Ontario

Sat 1/10

3:21 pm-11:39 am

1 stop18h 18m

$183

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Thu 1/29

10:01 pm-1:32 pm

1 stop17h 31m

Ontario

Sun 2/1

5:21 pm-8:50 pm

1 stop25h 29m

$187

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Tue 1/6

6:00 am-11:31 am

1 stop7h 31m

Ontario

Tue 1/13

1:11 pm-9:35 pm

1 stop6h 24m

$326

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Wed 1/7

8:45 am-12:47 pm

1 stop6h 02m

Ontario

Sat 1/10

1:24 pm-8:58 pm

1 stop5h 34m

$327

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Tue 1/13

9:57 am-8:58 pm

2 stops13h 01m

Ontario

Tue 1/20

5:05 am-1:16 pm

1 stop6h 11m

$335

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Tue 1/20

1:00 pm-9:05 pm

1 stop10h 05m

Ontario

Sun 1/25

10:30 pm-8:53 am

1 stop8h 23m

$341

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Thu 1/15

7:00 am-12:16 pm

1 stop7h 16m

Ontario

Tue 1/20

10:30 pm-8:53 am

1 stop8h 23m

$343

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Tue 1/20

2:50 pm-3:08 pm

1 stop26h 18m

Ontario

Tue 1/27

11:53 am-1:54 pm

1 stop24h 01m

$344

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Tue 1/20

2:50 pm-3:08 pm

1 stop26h 18m

Ontario

Sun 1/25

6:00 am-1:54 pm

1 stop29h 54m

$354

St. LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Mon 12/22

10:10 pm-5:22 pm

1 stop21h 12m

Ontario

Fri 1/2

5:54 pm-9:25 pm

1 stop25h 31m

$364

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/10

Showing 1-10 of 24 results

Compare providers for flights from St. Louis to Ontario

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Ontario in December.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy2 stars	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*1 star
eDreams	Price Accuracy3 stars	Trust Score*3 stars
Priceline	Price Accuracy1 star	Trust Score*3 stars
Cheapfaremart	Price Accuracy-	Trust Score*1 star
JustAirTicket	Price Accuracy-	Trust Score*1 star
Mytrip	Price Accuracy3 stars	Trust Score*3 stars
Cheapflightsfares	Price Accuracy3 stars	Trust Score*2 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 St. Louis-Ontario flights, users find the pricing of Mytrip to be most consistent on Cheapflights vs. Mytrip Users can find the same prices on St. Louis-Ontario flight deals on Cheapflights vs. Mytrip >95% of the time. Price accuracy is based on data collected from St. Louis-Ontario flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on St. Louis-Ontario flights, Cheapflights users trust Mytrip the most. Mytrip 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 St. Louis-Ontario 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 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.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Ontario

Prices

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

Currently, November is the cheapest month in which you can book a flight from St. Louis to Ontario (average of $67). Flying from St. Louis to Ontario in June is currently the most expensive (average of $248). 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 ONT?

It’s optimal to fly from St. Louis to Ontario in the evening. By choosing this option you can save up to 71% on the cost of your flight, compared to a flight in the morning.

What is the cheapest day to fly from St. Louis to Ontario?

Travelers seeking maximum savings on their St. Louis to Ontario flight should consider departing on Wednesday evenings when fares are most often at their lowest. Monday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing Ontario

Peruse reviews from past customers who have flown with Southwest, Delta, and United Airlines from St. Louis to Ontario 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.

Southwest

7.9

Good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

Southwest

7.9

Good

4,253 reviews

Southwest

7.9

Good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Delta

7.9

Good

8,008 reviews

Southwest

7.9

Good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

United Airlines

7.4

Good

9,095 reviews

Southwest

7.9

Good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

American Airlines

7.2

Good

11,050 reviews

Southwest

7.9

Good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Frontier

5.8

Fair

3,084 reviews

Southwest

7.9

Good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Related info for your journey

How long is the flight from St. Louis to Ontario?
There are many flights that can get you from St. Louis to Ontario in 6h 02m. Fly via Frontier, Delta, or United Airlines to get the fastest option. The distance between St. Louis and Ontario is about 1541 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.
What are the cheapest airlines flying from St. Louis to Ontario round-trip?
Frontier, at $128, was found to be the cheapest airline from St. Louis to Ontario.Alternate airlines to your destination round-trip include Delta and United Airlines. Frontier is priced at 64% lower than the current average price of a flight leaving 3 months from now.
What are the cheapest airlines to fly from St. Louis to Ontario one-way?
The cheapest airline one-way is Frontier, with whom users have recently found tickets for as low as $82. However, be on the lookout for offers from American Airlines and Delta, as they are both options that can get you from St. Louis to Ontario for a low price.
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 Ontario?
Currently, November is the cheapest month in which you can book a flight from St. Louis to Ontario (average of $67). Flying from St. Louis to Ontario in June is currently the most expensive (average of $248). 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

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Other flights to Ontario

Top 5 airlines flying from St. Louis to Ontario

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$137	Average$241	FlexibilityNo cancel fee	On-time62%
Delta	Cheapest$171	Average$371	FlexibilityNo cancel fee	On-timeN/A
American Airlines	Cheapest$264	Average$348	FlexibilityNo cancel fee	On-time71%
Southwest	Cheapest$292	Average$403	FlexibilityNo cancel fee	On-time63%
United Airlines	Cheapest$292	Average$416	FlexibilityNo cancel fee	On-time69%

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$74+ Cheap flights from St. Louis to Ontario (STL - ONT)

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 2/18. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from St. Louis to Ontario with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap 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 December 12, 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 December 12, 2025.

Find flight deals from St. Louis to Ontario

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Ontario that are best for you.

Compare providers for flights from St. Louis to Ontario

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 St. Louis to Ontario in December.

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.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Ontario

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

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

What is the cheapest day to fly from St. Louis to Ontario?

What’s the top layover airport for flights from St. Louis to Ontario?

What’s the cheapest layover airport for flights from St. Louis to Ontario?

What’s the fastest layover option from St. Louis to Ontario?

Which airport typically offers the quickest layover for flights from St. Louis to Ontario?

Reviews of airlines servicing Ontario

Peruse reviews from past customers who have flown with Southwest, Delta, and United Airlines from St. Louis to Ontario 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.

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.

How long is the flight from St. Louis to Ontario?

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

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

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?

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

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

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Alternative routes for St. Louis to Ontario

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Top 5 airlines flying from St. Louis to 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 December 12, 2025.