Flights from STL(St. Louis|St. Louis Lambert International Airport) to ONT(Los Angeles|Ontario International Airport)
Flights from St. Louis to Los Angeles
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STL to ONT, St. Louis Lambert International Airport to Ontario International Airport Cheap Flights
Find the best flight deals from St. Louis Lambert International Airport to Ontario International Airport
STL - ONT Flight Information
St. Louis → Los AngelesFlight information between St. Louis and Los Angeles
Cheapest one-way flight price
US$189
Cheapest return ticket price
US$506
Cheapest month
October
Peak season for travel
November
Flight distance
2,501.91 km
STL - ONT Cheap Flights
Compare flight options and choose the best deal for your journey
STL - ONT Flight Airlines
Major airlines flying this route
STL - ONT Route FAQs
Common questions about flights from STL to ONT
Based on HopeGoo data, Hawaiian Airlines offers one-way fares as low as US$189 on Cheapest nonstop routes (e.g. STL to ONT on Sat, Mar 7), while Hawaiian Airlines offers Cheapest nonstop round-trips from US$506 departing on Fri, Mar 13 and returning on Tue, Mar 17.
By analyzing data from all airlines on the HopeGoo flight calendar, it looks like the best time to book a flight from St. Louis to Ontario is around 40 days (6 weeks) in advance, and the best time to fly is usually on Tuesday, Wednesday, and Saturday. Tuesday typically offers the cheapest flights for departure, while Saturday offers the best return deals.
To find best deals on flights from St. Louis to Ontario, you can use various tools on HopeGoo: · Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on Sat, Mar 7, with one-way flights priced at just US$189. · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is Hawaiian Airlines. · Set up price alerts to easily monitor ticket prices without having to check every day. · Check HopeGoo flight deals and promo codes frequently. · Avoid peak season unless you book very early. It seems the peak season for Ontario travel is around November. · Get exclusive promo codes for HopeGoo app users.
The cheapest months to fly from St. Louis to Ontario is October, when demand for travel is lower.
After crunching the numbers on our February flight calendar, it's currently cheapest to fly from St. Louis to Ontario on February 28, 2026 with Frontier Airlines, with prices starting at US$208.
The time difference between Ontario and St. Louis is 2h.
Tickets can only be changed or canceled if permitted by airline policy. To submit a change or cancellation request, go to the flight bookings page, select the option to change or cancel your HopeGoo, choose the relevant passengers and segment, and submit a request. Please note that additional charges may apply according to the airline ticket policy. However, if the flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For more details about change and cancellation policies, please check the customer support pages.