Cheap Flight Tickets from St Louis (STL) to Ontario (ONT), Starting at $499

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

$612

DL Delta Airlines • 1 stop • 13h 47m

Dec 22 – Dec 26

The cheapest round trip flight from St Louis to Ontario (STL-ONT-STL) is currently $612

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Cheapest Direct Flight

$499

WN Southwest Airlines • nonstop • 6h 45m

Dec 22

The cheapest nonstop flight from St Louis to Ontario (STL-ONT) is currently $499

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Fastest Flight

6h 40m

The fastest nonstop flight from St Louis to Ontario (STL-ONT) takes 6h 40m

Top Airlines Flying from St Louis to Ontario

Delta Airline, DL

Delta Airlines

Southwest Airlines-WN

Southwest Airlines

United Airlines, UA

United Airlines

American Airlines, AA

American Airlines

Alaska Airlines -AS

Alaska Airlines

Aeromexico Airline (AM)

Aeromexico

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 22 - Dec 26, Economy
DL
St Louis → Ontario
13h 47m
11:51 AM - 6:18 PM • 1 stop
DL
St Louis → Ontario
15h 1m
7:00 AM - 6:01 PM • 1 stop
$612
Delta Airlines
Dec 22 - Dec 26, Economy
DL
St Louis → Ontario
12h 7m
6:00 AM - 11:27 AM • 1 stop
DL
St Louis → Ontario
10h 58m
7:00 AM - 3:58 PM • 1 stop
$612
Delta Airlines
Dec 22 - Dec 26, Economy
DL
St Louis → Ontario
18h 53m
2:15 PM - 11:48 PM • 1 stop
DL
St Louis → Ontario
15h 39m
12:00 PM - 11:39 PM • 1 stop
$779
Delta Airlines
Dec 22 - Dec 26, Economy
DL
St Louis → Ontario
17h 23m
7:30 AM - 4:13 PM • 1 stop
DL
St Louis → Ontario
15h 49m
10:59 PM - 10:48 AM • 1 stop
$814
Delta Airlines
Dec 22 - Dec 26, Economy
DL
St Louis → Ontario
17h 24m
1:30 PM - 10:14 PM • 1 stop
DL
St Louis → Ontario
15h 49m
10:59 PM - 10:48 AM • 1 stop
$1000
Delta Airlines
Dec 22 - Dec 26, Economy
DL
St Louis → Ontario
20h 23m
11:51 AM - 10:14 PM • 1 stop
DL
St Louis → Ontario
11h 53m
10:59 PM - 8:12 AM • 1 stop
$1000
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?
Yes, you can fly STL to ONT non-stop on
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 5:35 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 779
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 9:50 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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