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$65+ 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 8/13. Fares are subject to change and may not be available on all flights or dates of travel.
STL — ONT
Jul 31 — Aug 71
From?
To?
Wed 7/31
Wed 8/7
1 adult, Economy
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The best prices from Lambert-St Louis to Ontario are usually found in April or June, booked 37 days in advance, depart on a Monday or Thursday and return on a Saturday

Cheap flight deals from St. Louis to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Ontario (ONT). 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 July 26, 2024.

Popular in

December

Cheapest in

April

Round-trip from

$135
(FlightNetwork)

One-way from

$65
(Trip.com)
High demand for flights, 30% potential price rise
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Best time to find cheap flights, 47% potential price drop
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From Lambert-St Louis to Ontario
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One-way flight from Lambert-St Louis to Ontario
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What is the cheapest day to fly round-trip from St. Louis to Ontario?

Thursday flights are generally found to be more expensive for flights from St. Louis to Ontario. This shouldn’t discourage you from searching, as you can still find great deals by being flexible with your options. Use our search form to find deals on tickets to Ontario.

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

Travelers have found it’s best to book a flight 55 days in advance to save up to 75% compared to booking the same week of travel. As your travel date approaches, the cost of this flight route may potentially increase. While opting to book 55 days out may not be an option for all, there are still additional ways to secure a deal in the near future. You might find a flight from St. Louis to Ontario 1-2 weeks in advance for as low as $491, or $654 for flights within the next 24 hours.

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

Our data shows that April tends to be the cheapest month to fly to Ontario from St. Louis. Users have commonly found prices around $401 for the month, but tickets can be as low as $182. Due to multiple factors, prepare for potentially higher prices in March.

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 57% on the cost of your flight, compared to a flight in the morning.

Cheap St. Louis to Ontario flights in July & August 2024

Find cheap flight options from St. Louis to Ontario specifically for the months of July and August 2024. Explore affordable fares based on user searches. Over the last 7 days, Cheapflights users made 2,751,780 searches. Prices were last updated on July 26, 2024.
Scroll through some of the best deals on flights from St. Louis to Ontario in 2024. For more flight deals, be sure to check back very soon.
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/217:48 pmSTL - ONT
1 stop5h 51mFrontier
Wed 8/289:13 amONT - STL
1 stop10h 09mFrontier
Deal found 7/25$137
This mytrip.com deal was found by Cheapflights users on 7/24. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/193:15 pmSTL - ONT
1 stop11h 08mFrontier
Sun 8/251:35 pmONT - STL
1 stop6h 37mFrontier
Deal found 7/24$138
This mytrip.com deal was found by Cheapflights users on 7/26. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/178:55 pmSTL - ONT
1 stop12h 08mFrontier
Sat 8/248:06 pmONT - STL
1 stop24h 06mFrontier
Deal found 7/26$139
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/2110:22 pmSTL - ONT
1 stop10h 41mFrontier
Mon 8/2612:49 amONT - STL
1 stop15h 59mFrontier
Deal found 7/25$140
This mytrip.com deal was found by Cheapflights users on 7/26. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/2911:12 pmSTL - ONT
1 stop17h 49mFrontier
Mon 9/28:15 pmONT - STL
1 stop22h 21mFrontier
Deal found 7/26$142
This mytrip.com deal was found by Cheapflights users on 7/26. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/318:55 pmSTL - ONT
1 stop12h 08mFrontier
Mon 9/28:15 pmONT - STL
1 stop22h 21mFrontier
Deal found 7/26$143
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/139:36 pmSTL - ONT
1 stop19h 25mFrontier
Tue 8/276:31 pmONT - STL
1 stop22h 17mFrontier
Deal found 7/25$144
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/139:36 pmSTL - ONT
1 stop17h 06mFrontier
Mon 8/2612:49 amONT - STL
1 stop15h 59mFrontier
Deal found 7/25$145
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/89:44 pmSTL - ONT
1 stop17h 54mFrontier
Thu 8/151:35 pmONT - STL
1 stop6h 37mFrontier
Deal found 7/25$146

St. Louis to Ontario 2024 flight deals

Discover exclusive flight deals for travel between St. Louis and Ontario in 2024. Find excellent offers based on user searches. Over the last 7 days, Cheapflights users made 2,751,780 searches. Data last updated July 26, 2024.
Scroll through some of the best deals on flights from St. Louis to Ontario in 2024. For more flight deals, be sure to check back very soon.
This FlightNetwork deal was found by Cheapflights users on 7/26. 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 FlightNetwork is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/17:48 pmSTL - ONT
1 stop13h 29mFrontier
Sat 9/72:47 pmONT - STL
1 stop19h 07mFrontier
Deal found 7/26$135
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/217:48 pmSTL - ONT
1 stop5h 51mFrontier
Wed 8/289:13 amONT - STL
1 stop10h 09mFrontier
Deal found 7/25$137
This mytrip.com deal was found by Cheapflights users on 7/24. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/193:15 pmSTL - ONT
1 stop11h 08mFrontier
Sun 8/251:35 pmONT - STL
1 stop6h 37mFrontier
Deal found 7/24$138
This mytrip.com deal was found by Cheapflights users on 7/26. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/178:55 pmSTL - ONT
1 stop12h 08mFrontier
Sat 8/248:06 pmONT - STL
1 stop24h 06mFrontier
Deal found 7/26$139
This Frontier deal was found by Cheapflights users on 7/25. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/217:48 pmSTL - ONT
1 stop5h 51mFrontier
Wed 9/49:13 amONT - STL
1 stop10h 09mFrontier
Deal found 7/25$140
This Frontier deal was found by Cheapflights users on 7/25. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/17:48 pmSTL - ONT
1 stop13h 29mFrontier
Sat 9/78:05 pmONT - STL
1 stop13h 49mFrontier
Deal found 7/25$141
This mytrip.com deal was found by Cheapflights users on 7/26. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/2911:12 pmSTL - ONT
1 stop17h 49mFrontier
Mon 9/28:15 pmONT - STL
1 stop22h 21mFrontier
Deal found 7/26$142
This mytrip.com deal was found by Cheapflights users on 7/26. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/318:55 pmSTL - ONT
1 stop12h 08mFrontier
Mon 9/28:15 pmONT - STL
1 stop22h 21mFrontier
Deal found 7/26$143
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/139:36 pmSTL - ONT
1 stop19h 25mFrontier
Tue 8/276:31 pmONT - STL
1 stop22h 17mFrontier
Deal found 7/25$144

St. Louis to Ontario flights leaving soon

Find last-minute flight options from St. Louis to Ontario for spontaneous travel. Discover available flights and compare prices based on user searches. Secure great deals and offers for spontaneous trips with quick booking options. Over the last 7 days, Cheapflights users made 2,751,780 searches. Data last updated July 26, 2024.
Have a look at some of the last-minute flights available departing from St. Louis to Ontario. It's wise to confirm all flight details are correct before booking.
This Frontier deal was found by Cheapflights users on 7/24. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/3110:32 pmSTL - ONT
1 stop10h 31mFrontier
Fri 8/212:39 amONT - STL
1 stop6h 46mFrontier
Deal found 7/24$194
This mytrip.com deal was found by Cheapflights users on 7/24. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/3110:32 pmSTL - ONT
1 stop10h 31mFrontier
Sat 8/310:30 pmONT - STL
1 stop21h 01mFrontier
Deal found 7/24$195
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/19:44 pmSTL - ONT
1 stop21h 44mFrontier
Tue 8/65:26 pmONT - STL
1 stop26h 05mFrontier
Deal found 7/25$200
This mytrip.com deal was found by Cheapflights users on 7/26. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/210:32 pmSTL - ONT
1 stop13h 15mFrontier
Tue 8/67:26 pmONT - STL
1 stop24h 05mFrontier
Deal found 7/26$201
This Trip.com deal was found by Cheapflights users on 7/25. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/210:32 pmSTL - ONT
1 stop18h 55mFrontier
Tue 8/610:30 pmONT - STL
1 stop21h 01mFrontier
Deal found 7/25$202
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/35:38 pmSTL - ONT
1 stop15h 25mFrontier
Mon 8/54:31 pmONT - STL
1 stop27h 00mFrontier
Deal found 7/25$203
This Gotogate deal was found by Cheapflights users on 7/26. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/210:32 pmSTL - ONT
1 stop15h 20mFrontier
Sun 8/46:05 amONT - STL
1 stop25h 20mFrontier
Deal found 7/26$204
This CheapOair deal was found by Cheapflights users on 7/26. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/210:32 pmSTL - ONT
1 stop15h 20mFrontier
Sat 8/310:30 pmONT - STL
1 stop21h 01mFrontier
Deal found 7/26$210
This mytrip.com deal was found by Cheapflights users on 7/24. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/3110:32 pmSTL - ONT
1 stop14h 25mFrontier
Sat 8/1010:41 amONT - STL
1 stop23h 27mFrontier
Deal found 7/24$231

One-way flights to Ontario from St. Louis

Search for one-way flight options from St. Louis to Ontario. Find affordable one-way fares based on user searches. Compare prices and availability to plan your one-way journey according to your preferred dates and budget. Over the last 7 days, Cheapflights users made 2,751,780 searches. Data last updated July 26, 2024.
Users in need of a one-way flight from St. Louis to Ontario can choose from these deals. Users in need of a round-trip flight from St. Louis to Ontario instead should update the search form at the top of page.
This Trip.com deal was found by Cheapflights users on 7/24. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/137:48 pmSTL - ONT
1 stop13h 29mFrontier
Deal found 7/24$65
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/237:48 pmSTL - ONT
1 stop5h 51mFrontier
Deal found 7/25$69
This mytrip.com deal was found by Cheapflights users on 7/24. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/147:48 pmSTL - ONT
1 stop5h 51mFrontier
Deal found 7/24$70
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/195:20 pmSTL - ONT
1 stop8h 39mFrontier
Deal found 7/25$73
This mytrip.com deal was found by Cheapflights users on 7/24. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/207:48 pmSTL - ONT
1 stop6h 11mFrontier
Deal found 7/24$74
This Frontier deal was found by Cheapflights users on 7/24. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/193:15 pmSTL - ONT
1 stop11h 08mFrontier
Deal found 7/24$76
This Frontier deal was found by Cheapflights users on 7/25. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/127:51 pmSTL - ONT
1 stop5h 58mFrontier
Deal found 7/25$77
This Frontier deal was found by Cheapflights users on 7/24. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/73:16 pmSTL - ONT
1 stop5h 54mFrontier
Deal found 7/24$78
This mytrip.com deal was found by Cheapflights users on 7/25. 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.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/811:00 pmSTL - ONT
1 stop26h 59mFrontier
Deal found 7/25$82

Find flights from St. Louis to Ontario within your budget

Customize your flight search to find flights from St. Louis to Ontario 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 2,751,780 searches. Data last updated July 26, 2024.

Fly from

Any airport

Fly to

Any airport

Budget

$135 - $394

Route

Depart

Return

Price

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Sun 9/1

1 stop13h 29m

Ontario

Sat 9/7

1 stop19h 07m

$135

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Wed 8/21

1 stop5h 51m

Ontario

Wed 8/28

1 stop10h 09m

$137

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Mon 8/19

1 stop11h 08m

Ontario

Sun 8/25

1 stop6h 37m

$138

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Sat 8/17

1 stop12h 08m

Ontario

Sat 8/24

1 stop24h 06m

$139

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Wed 8/21

1 stop10h 41m

Ontario

Tue 8/27

1 stop21h 15m

$140

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Tue 8/13

1 stop6h 11m

Ontario

Tue 8/27

2 stops15h 52m

$273

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Tue 8/20

1 stop7h 29m

Ontario

Tue 9/3

1 stop5h 59m

$326

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Sat 8/24

2 stops8h 53m

Ontario

Sat 8/31

1 stop5h 53m

$331

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Wed 8/21

1 stop10h 33m

Ontario

Tue 8/27

2 stops15h 52m

$394

Flights are sorted by cheapest first

Deals found on 7/26

How far ahead should I book a flight from St. Louis to Ontario?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Ontario. Price data was last updated on July 25, 2024.
The price you pay for your flight from St. Louis to Ontario may vary depending on when you book. For the best chance of a lower fare, look to book 37 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
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What is the cheapest day to fly from St. Louis to Ontario?

Use this chart to determine the cheapest time to fly round-trip from St. Louis to Ontario. Price data was last updated on January 14, 2024.
Morning
Noon
Afternoon
Evening
All times are departure.
Travelers seeking maximum savings on their St. Louis to Ontario flight should consider departing on Sunday at noon when fares are most often at their lowest. Monday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.
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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.

Temperature and rainfall in Ontario by month

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

LAX

Temperature

57.2 - 73.4 °F

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).

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated July 26, 2024.
Peruse reviews from past customers who have flown with Frontier, Alaska Airlines and Delta from St. Louis to Ontario to help guide your decision. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.1
Very good
9,364 reviews

Food

7.2

Overall

8.1

Entertainment

7.2

Comfort

7.9

Crew

8.6

Boarding

8.2

Reviews

1 / 10

A/C was not working on the ground so it was 110 degrees on the plane when we boarded and we sat there for almost 40 minutes because Austin’s gate system has not kept up with growth. Not Alaska’s fault 100% but it was miserable.

Alaska Airlines
8.1
Very good
9,364 reviews
Alaska Airlines
8.1
Very good
9,364 reviews

Food

7.2

Overall

8.1

Entertainment

7.2

Comfort

7.9

Crew

8.6

Boarding

8.2

Reviews

1 / 10

A/C was not working on the ground so it was 110 degrees on the plane when we boarded and we sat there for almost 40 minutes because Austin’s gate system has not kept up with growth. Not Alaska’s fault 100% but it was miserable.

Delta
8.0
Very good
9,615 reviews
Alaska Airlines
8.1
Very good
9,364 reviews

Food

7.2

Overall

8.1

Entertainment

7.2

Comfort

7.9

Crew

8.6

Boarding

8.2

Reviews

1 / 10

A/C was not working on the ground so it was 110 degrees on the plane when we boarded and we sat there for almost 40 minutes because Austin’s gate system has not kept up with growth. Not Alaska’s fault 100% but it was miserable.

United Airlines
7.4
Good
10,000 reviews
Alaska Airlines
8.1
Very good
9,364 reviews

Food

7.2

Overall

8.1

Entertainment

7.2

Comfort

7.9

Crew

8.6

Boarding

8.2

Reviews

1 / 10

A/C was not working on the ground so it was 110 degrees on the plane when we boarded and we sat there for almost 40 minutes because Austin’s gate system has not kept up with growth. Not Alaska’s fault 100% but it was miserable.

American Airlines
7.3
Good
10,000 reviews
Alaska Airlines
8.1
Very good
9,364 reviews

Food

7.2

Overall

8.1

Entertainment

7.2

Comfort

7.9

Crew

8.6

Boarding

8.2

Reviews

1 / 10

A/C was not working on the ground so it was 110 degrees on the plane when we boarded and we sat there for almost 40 minutes because Austin’s gate system has not kept up with growth. Not Alaska’s fault 100% but it was miserable.

Frontier
6.2
Okay
3,835 reviews
Alaska Airlines
8.1
Very good
9,364 reviews

Food

7.2

Overall

8.1

Entertainment

7.2

Comfort

7.9

Crew

8.6

Boarding

8.2

Reviews

1 / 10

A/C was not working on the ground so it was 110 degrees on the plane when we boarded and we sat there for almost 40 minutes because Austin’s gate system has not kept up with growth. Not Alaska’s fault 100% but it was miserable.

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.

  • Can I find flights from St. Louis to Ontario for under $200 on Cheapflights?

    Yes, there are multiple flights from St. Louis to Ontario for under $200. The cheapest flight booked recently is on Frontier for just $135, but on average you can expect to pay $157.

  • Are there last-minute flights available from St. Louis to Ontario for under $200?

    There are currently 20+ open flights from St. Louis to Ontario within the next 7 days for less than $200.

  • What is the cheapest airline to fly from St. Louis to Ontario round-trip?

    Frontier, at $135, was found to be the cheapest airline from St. Louis to Ontario.. Frontier is priced at 61% 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 $65. However, be on the lookout for offers from United Airlines and American Airlines, as they are both options that can get you from St. Louis to Ontario for a low price.

  • What does STL to ONT mean?

    Lambert-St Louis Airport is STL and Ontario Airport is ONT. These codes are created by the International Air Transport Association (IATA) and airlines use them to identify the departing and arrival airports in the flight routes they service.

  • Can I find deals for flights from St. Louis to Ontario that include extra baggage allowance?

    The amount of baggage you can bring on your St. Louis to Ontario flight depends on the airline and the type of fare you've chosen. After entering your flight details, you'll be able to view the specific baggage policies for each deal in the search results. Keep in mind that certain deals may offer additional baggage allowance.

  • Can I find deals on flights from St. Louis to Ontario with specific airlines?

    Yes, Cheapflights allows you to browse and filter St. Louis to Ontario flight deals by airline. After entering your origin and destination, use the available filters to view flights offered by airlines.

  • 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.

  • Can I find deals for flights from St. Louis to Ontario that allow pets onboard?

    Many airlines flying from St. Louis to Ontario offer the option to travel with pets. After selecting a flight deal, you can find more information about the airline's pet policy on their official website or by contacting the airline directly. Please note that additional fees and restrictions may apply.

  • Can I find deals on last-minute flights from St. Louis to Ontario?

    Yes, you can often find last-minute deals on St. Louis to Ontario flights on Cheapflights. However, these deals can vary and may not always be available. We recommend checking back frequently or signing up for price alerts for the most up-to-date deals.

  • How recently were the St. Louis to Ontario flight deals updated?

    The St. Louis to Ontario flight deals you see on this page were last updated on 7/26.

  • 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: American Airlines, Delta or Frontier.

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

    Currently, October is the cheapest month in which you can book a flight from St. Louis to Ontario (average of $237). Flying from St. Louis to Ontario in July is currently the most expensive (average of $293). 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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Top 4 airlines flying from St. Louis to Ontario

Discover the top 4 airlines that operate flights from St. Louis to Ontario. 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 2,751,780 searches. Data last updated July 26, 2024.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$125Average$206FlexibilityNo cancel feeOn-time62%
DeltaCheapest$286Average$392FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$305Average$480FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$336Average$587FlexibilityNo cancel feeOn-time69%
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Search flights from St. Louis to Ontario by cabin class

Find flights from St. Louis to Ontario, based on your preferred cabin class, be it economy, premium economy, business, or first class.
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