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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
$689
Southwest Airlines
• 1 stop
• 13h 30m
Jul 17 – Jul 25
The cheapest round trip flight from St Louis to Ontario (STL-ONT-STL) is currently $689
Cheapest Direct Flight
$637
Southwest Airlines
• nonstop
• 5h 55m
Jul 17
The cheapest nonstop flight from St Louis to Ontario (STL-ONT) is currently $637
Fastest Flight
5h 55m
The fastest nonstop flight from St Louis to Ontario (STL-ONT) takes 5h 55m
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.
Jul 17 - Jul 25, Economy
St Louis → Ontario
13h 30m
9:15 AM - 3:25 PM • 1 stop
St Louis → Ontario
8h 30m
6:00 AM - 1:10 PM • 1 stop
Southwest Airlines
Jul 17 - Jul 25, Economy
St Louis → Ontario
10h
7:20 AM - 11:20 AM • 1 stop
St Louis → Ontario
10h 20m
6:00 AM - 2:20 PM • 1 stop
Southwest Airlines
Jul 17 - Jul 25, Economy
St Louis → Ontario
10h 35m
11:25 AM - 4:00 PM • 1 stop
St Louis → Ontario
9h 15m
10:00 AM - 5:55 PM • 1 stop
Southwest Airlines
Jul 17 - Jul 25, Economy
St Louis → Ontario
12h 20m
9:45 AM - 3:25 PM • 1 stop
St Louis → Ontario
8h 30m
6:00 AM - 1:10 PM • 1 stop
Southwest Airlines
Jul 17 - Jul 25, Economy
St Louis → Ontario
10h
4:00 PM - 8:00 PM • 1 stop
St Louis → Ontario
10h 10m
9:50 AM - 6:00 PM • 1 stop
Southwest Airlines
Flying to Ontario soon? We've surfaced some of the most affordable last-minute flights from St Louis to Ontario, ideal for urgent plans or spontaneous trips.
Jul 17 - Jul 25, Economy
St Louis → Ontario
13h 30m
9:15 AM - 3:25 PM • 1 stop
St Louis → Ontario
8h 30m
6:00 AM - 1:10 PM • 1 stop
Southwest Airlines
Jul 17 - Jul 25, Economy
St Louis → Ontario
10h
7:20 AM - 11:20 AM • 1 stop
St Louis → Ontario
10h 20m
6:00 AM - 2:20 PM • 1 stop
Southwest Airlines
Jul 17 - Jul 25, Economy
St Louis → Ontario
10h 35m
11:25 AM - 4:00 PM • 1 stop
St Louis → Ontario
9h 15m
10:00 AM - 5:55 PM • 1 stop
Southwest Airlines
Jul 17 - Jul 25, Economy
St Louis → Ontario
12h 20m
9:45 AM - 3:25 PM • 1 stop
St Louis → Ontario
8h 30m
6:00 AM - 1:10 PM • 1 stop
Southwest Airlines
Jul 17 - Jul 25, Economy
St Louis → Ontario
10h
4:00 PM - 8:00 PM • 1 stop
St Louis → Ontario
10h 10m
9:50 AM - 6:00 PM • 1 stop
Southwest Airlines
Looking for the fastest way to Ontario? These direct flight options from STL to ONT offer both convenience and value—no layovers, just straight to your destination.
Jul 17 - Jul 25, Economy
St Louis → Ontario
5h 55m
9:55 PM - 11:50 PM • nonstop
St Louis → Ontario
5h 40m
5:05 AM - 10:45 AM • nonstop
Southwest Airlines
Jul 17 - Jul 25, Economy
St Louis → Ontario
5h 55m
8:10 AM - 10:05 AM • nonstop
St Louis → Ontario
5h 40m
5:05 AM - 10:45 AM • nonstop
Southwest 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?
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 5:45 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 WN : USD 689
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 9:55 pm
Hotels in Ontario (ONT)
5 hotels near Ontario International — compare rates from top booking sites.
5-star hotel
The Ritz-Carlton, Rancho Mirage
📍 68900 Frank Sinatra Dr, Rancho Mirage, California 92270
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4-star hotel
Ayres Hotel Chino Hills
📍 4785 Chino Hills Pkwy, Chino hills, California 91709
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4-star hotel
Pacific Palms Resort
📍 1 Industry Hills Pkwy, City Of Industry, California 91744
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4-star hotel
Arrowhead Inn & Suites
📍 250 North 9th Street, Colton, California 92324
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4-star hotel
Ayres Suites Diamond Bar
📍 21951 Golden Springs Dr, Diamond Bar, California 91765
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Search Deals →
Hotel Deals in Ontario (OR)
OYO Rooms
Motel 6 Ontario, OR
8.0/10
★★☆☆☆
Resort villa
97.0 rooms
✓ Free WiFi
📍 275 NE 12th St, Ontario (OR), Oregon
At Motel 6 Ontario, OR, exceptional service and top-notch amenities create a memorable experience for guests. Complimentary internet access is available in the resort villa to ensure you stay connect…
Check-in 03:00 PM · Check-out 11:00 AM
$81/night
View Deal
Budget Inn Ontario
6.9/10
★★☆☆☆
✓ Breakfast
$88/night
View Deal
Choice Hotels
Rodeway Inn & Suites Ontario
8.3/10
★★☆☆☆
Hotel
20.0 rooms
✓ Free WiFi
✓ Breakfast
📍 139 NE Goodfellow Street, Building B, Ontario (OR), Oregon
Experience an abundance of unparalleled facilities and features at Rodeway Inn & Suites. Maintain seamless communication using the complimentary Wi-Fi at hotel.For visitors traveling by automobile, c…
Check-in 03:00 PM · Check-out 11:00 AM
$100/night
View Deal
Wyndham Hotels & Resorts
Super 8 By Wyndham Ontario
7.0/10
★★☆☆☆
Hotel
71.0 rooms
✓ Free WiFi
✓ Breakfast
📍 615 E Idaho Ave, Ontario (OR), Oregon
Super 8 By Wyndham Ontario offers top-notch services and amenities, ensuring guests experience utmost comfort. Share your photos and respond to emails at your convenience, thanks to the free Wi-Fi in…
Check-in 03:00 PM · Check-out 11:00 AM
$101/night
View Deal
Choice Hotels
Quality Inn Ontario
8.3/10
★★★☆☆
Hotel
63.0 rooms
✓ Free WiFi
✓ Breakfast
📍 139 NE Goodfellow Street, Ontario (OR), Oregon
Experience an abundance of unparalleled facilities and features at Quality Inn. Maintain seamless communication using the complimentary Wi-Fi at hotel. For visitors traveling by automobile, complimen…
Check-in 03:00 PM · Check-out 11:00 AM
$114/night
View Deal
-20.0%
Sonesta
Red Lion Inn & Suites Ontario
7.6/10
★★☆☆☆
Hotel
63.0 rooms
✓ Free WiFi
✓ Breakfast
📍 266 Goodfellow St, Ontario (OR), Oregon
Experience an abundance of unparalleled facilities and features at Red Lion Inn & Suites Ontario. Maintain seamless communication using the complimentary Wi-Fi at hotel. For visitors traveling by aut…
Check-in 03:00 PM · Check-out 11:00 AM
$133/night
View Deal
Choice Hotels
Sleep Inn Ontario
8.9/10
★★★☆☆
Hotel
65.0 rooms
✓ Free WiFi
✓ Breakfast
📍 1221 S.E. 1st Ave, Ontario (OR), Oregon
At Sleep Inn, exceptional service and top-notch amenities create a memorable experience for guests.Complimentary internet access is available in the hotel to ensure you stay connected during your vis…
Check-in 03:00 PM · Check-out 11:00 AM
$137/night
View Deal
InterContinental Hotels Group
Holiday Inn Ontario By IHG
7.6/10
★★★☆☆
Hotel
98.0 rooms
✓ Free WiFi
✓ Breakfast
📍 1249 Tapadera Ave.,, Ontario (OR), Oregon
Experience an abundance of unparalleled facilities and features at Holiday Inn Ontario. Maintain seamless communication using the complimentary Wi-Fi at hotel.For visitors traveling by automobile, co…
Check-in 03:00 PM · Check-out 11:00 AM
$205/night
View Deal
InterContinental Hotels Group
Holiday Inn Express Hotel & Suites Ontario By IHG
9.2/10
★★★☆☆
Hotel
96.0 rooms
✓ Free WiFi
✓ Breakfast
📍 212 Se 10Th Street, Ontario (OR), Oregon
Holiday Inn Express Hotel & Suites Ontario By IHG provides flawless service and all the necessary facilities for visitors. Stay connected with your associates, as complimentary Wi-Fi is available dur…
Check-in 03:00 PM · Check-out 12:00 PM
$217/night
View Deal
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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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