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Uncover the best deals on St Louis to Ontario flights by comparing fares from hundreds of airlines and agencies.
Good to Know: Cheapest and Fastest STL - ONT Flights
Useful information for finding best airline tickets from Lambert St Louis International to Ontario International on your next trip.
Cheapest Round Trip Flight
$396
Southwest Airlines
• 1 stop
• 22h 10m
Dec 29 – Dec 29
The cheapest round trip flight from St Louis to Ontario (STL-ONT-STL) is currently $396
Fastest Flight
12h 25m
The fastest nonstop flight from St Louis to Ontario (STL-ONT) takes 12h 25m
Top Airlines Flying from St Louis to Ontario
Latest Flight Deals from St Louis (STL) to Ontario (ONT)
Compare and book low fare round-trip air tickets from St Louis to Ontario. Ideal for travelers with confirmed return itineraries.
Dec 29 - Dec 29, Economy
St Louis → Ontario
22h 10m
6:20 AM - 5:50 PM • 1 stop
St Louis → Ontario
19h
9:30 PM - 11:10 AM • 1 stop
Southwest Airlines
Dec 29 - Jan 02, Economy
St Louis → Ontario
13h 40m
5:25 AM - 11:45 AM • 1 stop
St Louis → Ontario
5h 25m
7:25 PM - 12:50 AM • nonstop
Southwest Airlines
Dec 29 - Jan 02, Economy
St Louis → Ontario
12h 25m
3:05 PM - 8:50 PM • 1 stop
St Louis → Ontario
5h 30m
5:05 AM - 10:35 AM • nonstop
Southwest Airlines
Dec 29 - Jan 02, Economy
St Louis → Ontario
13h 55m
11:41 AM - 6:16 PM • 1 stop
St Louis → Ontario
8h 24m
4:45 PM - 11:49 PM • 1 stop
American Airlines
Dec 29 - Jan 02, Economy
St Louis → Ontario
15h 15m
3:24 PM - 10:39 PM • 1 stop
St Louis → Ontario
5h 35m
6:16 PM - 11:51 PM • nonstop
Alaska Airlines
FAQs on St Louis to Ontario Flights
What are the airports in St Louis?
STL
What’s the most popular airline flying from STL to ONT?
The most popular airline flying from St Louis to Ontario are
Can I fly from STL to ONT non-stop?
NO
Which airlines fly nonstop between St Louis and Ontario?
The non-stop flights between St Louis and Ontario are .
What’s the earliest departure time from STL to ONT Airport?
The earliest flight leaves STL at 5:25 am and lands in ONT - Ontario International
What are the airports in Ontario?
ONT
Can I make changes to my St Louis to Ontario flight tickets or cancel them on FareLeaders.com?
No. We are an airfare comparison site. All the tickets are booked by the travel agent offering the flight deal and any changes or cancellations to be made are directly done directly by them or the airlines.
Can I cancel my flight tickets from STL to ONT?
Read the fare rules of the St Louis to Ontario air tickets booked. Some airlines allow you to cancel the tickets within a stipulated time period with a cancellation fee.
Which airline alliances offer flights from St Louis and Ontario?
operate flights between St Louis and Ontario
How long does a flight from St Louis to Ontario take?
It takes approximately 4 hour to fly non-stop from STL to ONT, which is 1545.85 miles by air.
Which airlines provide the cheapest flights from St Louis (STL) to Ontario (ONT) ?
In the past couple of days, the cheapest tickets to ONT from STL were found on AS : USD 1092
Do I need a passport to fly between STL and ONT?
No
What’s the latest departure time from STL to ONT ?
The last flight leaves STL at 3:24 pm
St Louis (STL) to Ontario (ONT): Airport Information
| Origin Airport | Lambert St Louis International , St Louis, US |
| Destination Airport | Ontario International , Ontario, US |
| Distance | 1546 miles |
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