₩225,800 Cheap Flights from St. Louis (STL) to Ontario (ONT)

View ₩225,800 flight on Wed, Jun 4, 2025Opens in a new window

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Cheap Flights from St. Louis to Ontario (STL-ONT)

Prices were available within the past 7 days and start at ₩225,800 for one-way flights and ₩501,900 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Hawaiian Airlines
Tue, Sep 30 - Wed, Oct 1
STL
St. Louis
ONT
Ontario
₩501,900 Roundtrip, found 4 days ago
₩501,900
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Tue, Sep 30 from St. Louis to Ontario, returning Wed, Oct 1, priced at ₩501,900 found 4 days ago
Delta
Wed, Oct 1 - Thu, Oct 2
STL
St. Louis
ONT
Ontario
₩502,500 Roundtrip, found 4 days ago
₩502,500
Roundtrip
found 4 days ago
Select Delta flight, departing Wed, Oct 1 from St. Louis to Ontario, returning Thu, Oct 2, priced at ₩502,500 found 4 days ago
Hawaiian Airlines
Tue, Sep 30 - Tue, Oct 7
STL
St. Louis
ONT
Ontario
₩504,900 Roundtrip, found 4 days ago
₩504,900
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Tue, Sep 30 from St. Louis to Ontario, returning Tue, Oct 7, priced at ₩504,900 found 4 days ago
Delta
Tue, Sep 30 - Sat, Oct 4
STL
St. Louis
ONT
Ontario
₩505,500 Roundtrip, found 4 days ago
₩505,500
Roundtrip
found 4 days ago
Select Delta flight, departing Tue, Sep 30 from St. Louis to Ontario, returning Sat, Oct 4, priced at ₩505,500 found 4 days ago
Delta
Fri, Jul 4 - Tue, Jul 15
STL
St. Louis
ONT
Ontario
₩508,400 Roundtrip, found 2 days ago
₩508,400
Roundtrip
found 2 days ago
Select Delta flight, departing Fri, Jul 4 from St. Louis to Ontario, returning Tue, Jul 15, priced at ₩508,400 found 2 days ago
Delta
Thu, Oct 2 - Sat, Oct 4
STL
St. Louis
ONT
Ontario
₩546,500 Roundtrip, found 4 days ago
₩546,500
Roundtrip
found 4 days ago
Select Delta flight, departing Thu, Oct 2 from St. Louis to Ontario, returning Sat, Oct 4, priced at ₩546,500 found 4 days ago
Hawaiian Airlines
Tue, Sep 30 - Fri, Oct 3
STL
St. Louis
ONT
Ontario
₩556,200 Roundtrip, found 4 days ago
₩556,200
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Tue, Sep 30 from St. Louis to Ontario, returning Fri, Oct 3, priced at ₩556,200 found 4 days ago
Delta
Wed, Oct 1 - Fri, Oct 3
STL
St. Louis
ONT
Ontario
₩556,700 Roundtrip, found 4 days ago
₩556,700
Roundtrip
found 4 days ago
Select Delta flight, departing Wed, Oct 1 from St. Louis to Ontario, returning Fri, Oct 3, priced at ₩556,700 found 4 days ago
United
Fri, Jul 4 - Tue, Jul 15
STL
St. Louis
ONT
Ontario
₩612,600 Roundtrip, found 2 days ago
₩612,600
Roundtrip
found 2 days ago
Select United flight, departing Fri, Jul 4 from St. Louis to Ontario, returning Tue, Jul 15, priced at ₩612,600 found 2 days ago
American Airlines
Fri, Jul 4 - Tue, Jul 15
STL
St. Louis
ONT
Ontario
₩640,300 Roundtrip, found 2 days ago
₩640,300
Roundtrip
found 2 days ago
Select American Airlines flight, departing Fri, Jul 4 from St. Louis to Ontario, returning Tue, Jul 15, priced at ₩640,300 found 2 days ago
Flights from St. Louis (STL) to Ontario (ONT)
Origin airport
Lambert-St. Louis Intl.
Destination airport
Los Angeles - Ontario Intl.
Roundtrip price
₩501,900
Distance
2467 km

St. Louis to Los Angeles Flights

Sometimes you just need to get out of town or maybe you’re looking for a change of scenery. Regardless of the reason, a flight from St. Louis to Los Angeles will do just the trick! Go on, plan to see all the famous landmarks and eat your weight in the local cuisine. Your trip is beckoning, so answer the call by packing your suitcase and filling your travel itinerary with exploring Los Angeles.

Whether you’re flying for business or jet-setting on your personal time, you’ve come to the right place. Here at Expedia.com, we’ll pair you up with STL to ONT flights that won’t make your bank account wince. Ready to temporarily leave behind St. Louis for new horizons? Browse through our cheap airfare, and filter by flight times and dates until you find just what you had in mind. From flights without layovers to ones that arrive early in the morning, you’ll come across plane tickets that suit your travel preferences. You can even bundle your flight to ONT with hotels and car rentals to score even bigger savings.

All set to hit the clouds? Book your travel arrangements with us today and have left-over money to put toward your travel outings and adventures.

Frequently asked questions

How much is a flight from STL to Los Angeles - Ontario Intl. Airport (ONT)?
Based on airfares listed within the last 7 days on Expedia for flights departing within the next year, round-trip flights between St. Louis Lambert International Airport and Ontario Airport start from ₩501,900. Book today to score the best price for your journey. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from Lambert-St. Louis Intl. Airport (STL) to ONT?
Most flights can be canceled online, but whether you are charged a fee depends on your airline. If you do need to cancel your break, follow the instructions in the Customer Service Portal.
How do I find cheap flights from Lambert-St. Louis Intl. Airport (STL) to Los Angeles - Ontario Intl. Airport (ONT) that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you’re searching for STL to Los Angeles - Ontario Intl. Airport (ONT) flights, you’ll see a “no change fees” filter for you to select.
How far is the flight from Lambert-St. Louis Intl. Airport (STL) to Los Angeles - Ontario Intl. Airport (ONT)?
The flight distance from St. Louis to Ontario is 2,500 kilometers. Bring a drink, a few snacks and an interesting book to read. Keep yourself entertained and time will zip by.
Which airlines fly direct from St. Louis Lambert International Airport to Ontario Airport?
Unfortunately, there are no airlines that fly direct between Lambert-St. Louis Intl. Airport (STL) and Ontario Airport. You’ll need to book a flight with one or more stops.
Are St. Louis Lambert International Airport to Ontario Airport flight tickets cheaper when they're purchased at the last minute?
It is possible to score an amazing last-minute deal from Lambert-St. Louis Intl. Airport (STL) to Ontario Airport, but it’s also possible to miss out altogether! As many airlines publish prices up to 12 months in advance, it’s worthwhile keeping an eye on fares early and being ready to book when you see a bargain. Expedia compares air carrier prices and updates flight deals regularly, so you can be certain you’re always getting the latest offers.

Explore a world of travel with Expedia

Ontario nearby Airports

Los Angeles

St. Louis to Los Angeles Intl.
₩593,400
*Available to Expedia members.