Cheap Flight Tickets from St Louis (STL) to Ontario (ONT), Starting at $760

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

$760

DL Delta Airlines • 1 stop • 11h 46m

Nov 06 – Nov 15

The cheapest round trip flight from St Louis to Ontario (STL-ONT-STL) is currently $760

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Fastest Flight

9h

The fastest nonstop flight from St Louis to Ontario (STL-ONT) takes 9h

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.

Nov 06 - Nov 15, Economy
DL
St Louis → Ontario
11h 46m
6:00 AM - 11:06 AM • 1 stop
DL
St Louis → Ontario
15h 38m
12:18 PM - 11:56 PM • 1 stop
$760
Delta Airlines
Nov 06 - Nov 15, Economy
DL
St Louis → Ontario
11h 45m
2:25 PM - 7:30 PM • 1 stop
DL
St Louis → Ontario
8h 50m
6:00 AM - 1:30 PM • 1 stop
$760
Delta Airlines
Nov 06 - Nov 15, Economy
DL
St Louis → Ontario
11h 51m
5:00 PM - 10:11 PM • 1 stop
DL
St Louis → Ontario
15h 38m
12:18 PM - 11:56 PM • 1 stop
$760
Delta Airlines
Nov 06 - Nov 14, Economy
WN
St Louis → Ontario
9h
7:20 PM - 11:00 PM • 1 stop
WN
St Louis → Ontario
8h 20m
11:20 AM - 6:20 PM • 1 stop
$794
Southwest Airlines
Nov 06 - Nov 14, Economy
WN
St Louis → Ontario
9h
7:20 PM - 11:00 PM • 1 stop
WN
St Louis → Ontario
5h 30m
10:50 AM - 4:20 PM • nonstop
$806
Southwest Airlines
Nov 06 - Nov 15, Economy
DL
St Louis → Ontario
15h 30m
12:00 PM - 7:30 PM • 1 stop
DL
St Louis → Ontario
15h 38m
12:18 PM - 11:56 PM • 1 stop
$838
Delta Airlines

Fly from St Louis to Ontario with the Best Airfare Deals on FareLeaders

Looking for a cheap last-minute deal or the best round-trip flight from St Louis to Ontario? Find the biggest savings on one-way and round-trip tickets right here.

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 6:00 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 DL : USD 760
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 7:20 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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