ONT to STL (Ontario to St. Louis) Flights

Last Minute Flights from ONT to STL

Price found within the past 7 days for the specified period. Click for updated prices.

OriginDestinationTravel DatesFlights From*
ONTSt. LouisMarch 27 to March 29$355
*Prices include taxes and fees

Cheapest ONT to STL Flights

Price found within the past 7 days for the specified period. Click for updated prices.

OriginDestinationTravel DatesFlights From*
ONTSt. LouisApril 17 to April 19$160
ONTSt. LouisApril 15 to April 22$317
ONTSt. LouisApril 7 to April 21$317
ONTSt. LouisApril 15 to April 22$317
ONTSt. LouisApril 15 to April 22$317
*Prices include taxes and fees
ONT to STL Flight Details
Origin airport
Los Angeles - Ontario Intl.
Origin airport IATA code
ONT
Destination airport
Lambert-St. Louis Intl.
Destination airport IATA code
STL
Distance
1541 mi

Frequently asked questions

What airlines fly direct from ONT to Lambert-St. Louis Intl. Airport (STL)?
Unfortunately, it's not possible to fly straight from Los Angeles - Ontario Intl. Airport (ONT) to STL. Get to St. Louis by reserving a flight with at least one stop in between. If you've got the time, why not spend a day or two in your layover city?
How many flights are there from ONT to STL?
There are roughly 25 flights per day from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.), so you have ample opportunities to get to St. Louis. Just pick out a time and date that works for you and lock in your fare.
How long does it take to fly from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
On average, 5 hours. On a daytime flight? Request a seat near the window and gaze out at the changing views. Alternatively, if you're flying from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) in the evening, close your eyes and touch down in St. Louis rested and recharged.
What is the flight distance from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The Ontario, CA (ONT-Los Angeles - Ontario Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) route covers 1,550 miles (2,500 1) and is classed as a medium-haul flight. If you're searching for comfort — and you've found a bargain — consider upgrading to a premium or business class seat.
How many morning flights are there from ONT to STL?
With 81 morning flights each week from ONT to STL to select from, you'll be jumping out of bed and jetting off in no time.

  • American Airlines (AA) has 35 weekly flights that depart before midday. The earliest one you can hop on is 6:00AM.
  • Alaska Airlines (AS) is another option. It has 14 morning flights, with the earliest departing at 6:00AM.
  • Fly before midday with Delta Air Lines (DL) and you'll have approximately 14 flights each week to pick from. 5:45AM is the first flight of the day from ONT to STL.

How many afternoon flights are there from ONT to STL?
If the words "early start" just aren't in your vocabulary, get aboard one of the 99 weekly afternoon and evening flights from ONT to STL.

  • Consider booking your seat with American Airlines (AA). This carrier has 37 flights each week that leave after noon. The earliest service is 12:50PM.
  • If you'd like to go with Delta Air Lines (DL), you can take your pick of 24 weekly afternoon and evening flights that depart ONT from 12:35PM onward.
  • Another top option is Frontier Airlines (F9). It has 21 afternoon and evening flights each week from 12:29PM onward.

What is the earliest departure time out of Ontario to St. Louis?
Leave ONT at 12:55AM and hit the tarmac at STL at 8:47AM. This is the earliest service you can book on this route.
What is the latest departure time out of Ontario to St. Louis?
From ONT, the latest flight you can catch jets out at 11:59PM and lands at 10:59PM at STL. If you don't do early starts, this is the flight for you!
What is the average price from Ontario to St. Louis?
On average, the cheapest price for round-trip flights from ONT to STL is $160. Score your own deal by locking in your seats early. This price was available on Flights.com within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

Ontario to St. Louis Flights

Whether it’s for an obligation or the sake of your sanity, sometimes you need to get away. Maybe you need flights from Ontario to St. Louis to attend your cousin’s wedding, to pitch a business idea to your boss, or simply treat yourself to a mini vacation. Regardless of the reasons behind packing your bags and needing to find our cheapest flights from ONT to STL, we’ve got you covered here at Flights.com.

We present you with some of the most affordable deals on airfare, so stop that Google flights search. We want you to spend less on your flight from Ontario to St. Louis, so you can spend more during your getaway. With Flights.com, you’ll find it simple to land airline tickets with itineraries matching your travel schedule. What’s more, we provide you with all the information you need to confidently make reservations on your family, business, or personal trip.

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