Cheap Flight Tickets from St Louis (STL) to Ontario (ONT), Starting at $355

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

$355

WN Southwest Airlines • 1 stop • 16h 50m

Nov 25 – Nov 30

The cheapest round trip flight from St Louis to Ontario (STL-ONT-STL) is currently $355

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Fastest Flight

9h

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

Top Airlines Flying from St Louis to Ontario

Southwest Airlines-WN

Southwest Airlines

Delta Airline, DL

Delta Airlines

American Airlines, AA

American Airlines

United Airlines, UA

United Airlines

Alaska Airlines -AS

Alaska Airlines

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 25 - Nov 30, Economy
WN
St Louis → Ontario
16h 50m
2:20 PM - 10:30 PM • 1 stop
WN
St Louis → Ontario
5h 25m
5:00 AM - 10:25 AM • nonstop
$355
Southwest Airlines
Nov 25 - Nov 30, Economy
WN
St Louis → Ontario
10h 50m
7:35 AM - 12:25 PM • 1 stop
WN
St Louis → Ontario
5h 25m
5:00 AM - 10:25 AM • nonstop
$369
Southwest Airlines
Nov 25 - Nov 30, Economy
WN
St Louis → Ontario
15h
5:25 AM - 12:25 PM • 1 stop
WN
St Louis → Ontario
5h 25m
5:00 AM - 10:25 AM • nonstop
$369
Southwest Airlines
Nov 25 - Nov 30, Economy
DL
St Louis → Ontario
10h 49m
7:00 PM - 11:49 PM • 1 stop
DL
St Louis → Ontario
10h 31m
8:00 AM - 4:31 PM • 1 stop
$604
Delta Airlines
Nov 25 - Nov 30, Economy
DL
St Louis → Ontario
13h 43m
2:31 PM - 8:54 PM • 1 stop
DL
St Louis → Ontario
9h 2m
3:40 PM - 11:22 PM • 1 stop
$604
Delta Airlines
Nov 25 - Nov 30, Economy
DL
St Louis → Ontario
11h 52m
7:08 AM - 12:20 PM • 1 stop
DL
St Louis → Ontario
8h 42m
5:18 PM - 12:40 AM • 1 stop
$604
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 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 DL : USD 604
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 7:00 pm

Essential Information for Booking Flights from St Louis (STL) - AI Insights

What's the cheapest airline from stl to ont?
For a one-way First class ticket from Lambert St Louis International Airport (stl) to Ontario International Airport (ont) with 6 passengers, booking 6 days in advance, you can expect to pay for a luxury cabin with suites and fine dining. Low fares are not typically available for luxury flights, but you can find budget-friendly options for other cabin classes. Consider Southwest Airlines (WN) for a competitive airfare.
What's the popular airline to fly from stl to ont?
Southwest Airlines offers flights from Lambert St Louis International Airport (stl) to Ontario International Airport (ont) with a popular First class option. For a one-way trip with 6 passengers, booking in advance is recommended. You can find affordable airfares on their website.
What's the cheapest day of the week to fly from stl to ont?
The cheapest day to fly from St. Louis (STL) to Ontario (ONT) is Thursday. Flying on this day can result in budget-friendly flights and savings. Consider booking your flight on Thursday for a more affordable airfare.
What's the cheapest month to fly from stl to ont?
The cheapest month to fly from St. Louis to Ontario is October, as it is typically the low season for air travel in this region. You can expect to find budget-friendly flights during this time.
Which airline/airlines fly from stl to ont?
The airlines that fly from Lambert St Louis International Airport (STL) to Ontario International Airport (ONT) include Southern Airways (9X), United Airlines (UA), Delta Airlines (DL), American Airlines (AA), Alaska Airlines (AS), Frontier Airlines (F9), Aeromexico (AM), and Southwest Airlines (WN). You can find low fares on these airfares for a budget-friendly flight.
What is the best time to book an airfare from Milwaukee to Ontario for the cheapest airfare?
The cheapest time to book an airfare from Milwaukee to Ontario is October, with advance booking days of 6 days.
How many advance booking days are required for a one-way trip from Ontario to Milwaukee?
A one-way trip from Ontario to Milwaukee requires 6 advance booking days.
Can I book a First class cabin with suites and fine dining on flights from St Louis to Ontario?
Yes, you can book a First class cabin with suites and fine dining on flights from St Louis to Ontario with Southern Airways (9X) or United Airlines (UA).
What is the average cost of airfare for a weekend getaway from Milwaukee to Ontario?
The average cost of airfare for a weekend getaway from Milwaukee to Ontario is $airfare.
How can I find the best airline for my needs and budget on fareleaders.com?
You can find the best airline for your needs and budget on fareleaders.com by comparing airfares and using our airline comparison tool.
Can I book a busco or pasaje ticket from Ontario to Milwaukee?
No, you cannot book a busco or pasaje ticket from Ontario to Milwaukee.
How do I use the web to compare airfares and find the best agency for my travel needs?
You can use the web to compare airfares and find the best agency for your travel needs by visiting fareleaders.com and using our airline comparison tool.

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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