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Cheap ONT to STL Flights

Prices found within past 7 days. Prices and availability subject to change. Additional terms may apply.

Ontario to St. Louis route information

Origin Airport Los Angeles - Ontario Intl.
Destination Airport Lambert-St. Louis Intl.
Airlines Serving Alaska Airlines, American Airlines, Delta, Frontier Airlines, United
Flight Price $316
Distance 1,541 mi

Orange County

$227.98

Long Beach

$343.99

Los Angeles

$216.38

Burbank

$348.00

Cheap ONT to STL Flights

  • Question : Can I change the date of my flight?
    Answer : You sure can and you may save by doing it. The cheapest day to fly in June is Tuesday. Being flexible with your travel days can provide you extra savings when booking.
  • Question : How long do most people visit Saint Louis?
    Answer : Of course, you're not most people, but if you were, you'd stay around five days.
  • Question : What is the cheapest day to fly?
    Answer : The cheapest day to fly from Ontario to Saint Louis is on Tuesday. If you are trying to save a little money on your next vacation look for flights on that day.
  • Question : What is the cheapest day to fly to Saint Louis?
    Answer : As of May 20th, the cheapest day to fly from Ontario to Saint Louis is Jun 18th. Tickets are currently $278, 46% less than the average price.
  • Question : What is the cheapest airline flying from Ontario to Saint Louis?
    Answer : American Airlines is your best travel expert for finding that in demand low fare. They offer fares as low as $262, while prices for similar flights are as high as $1,071.
  • Question : How much is a plane ticket to Saint Louis (STL) from Ontario (ONT)? Cost can range from $262 to $1,071, prices for ONT to STL change less than most routes in the United States. Don't forget, booking ahead can save you some money you can use to treat yourself while on your trip. And who doesn't like to treat themselves?
    Answer : Cost can range from $262 to $1,071, prices for ONT to STL change less than most routes in the United States. Don't forget, booking ahead can save you some money you can use to treat yourself while on your trip. And who doesn't like to treat themselves?
  • Question : Which airline has the least delays from Ontario to Saint Louis?
    Answer : Booking with NetJets Aviation means you will arrive to Saint Louis when you are supposed to. In fact, this timely airline has a 100% average for landing before the plane turns into a pumpkin. Of course, it never hurts to be prepared. If you’re on UPS, be sure to sign up for the delay notifications to stay up to date with your flight’s status.