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Amazing United STL to ONT Flight Deals

The cheapest flights to Los Angeles - Ontario Intl. found within the past 7 days were $267 round trip and $132 one way. Prices and availability subject to change. Additional terms may apply.



FAQs about United Airlines Flights from STL to ONT

What terminal is United Airlines at St. Louis Lambert International Airport?

Once you've received the boarding pass for your flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.), you should be able to identify exactly which terminals United Airlines flies in and out of. If not, consult your airline or do some research online for that information.

Are there United Airlines non-stop flights from STL to ONT?

United Airlines doesn't operate direct flights between St. Louis, MO (STL-Lambert-St. Louis Intl.) and Ontario, CA (ONT-Los Angeles - Ontario Intl.), so plan on making at least one stopover. If you have time to spare between flights, browse the airport shops while you wait for your connection.

How long is an United Airlines flight from STL to ONT?

Your United Airlines flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.) will take about 5 hours and 23 minutes. But there are loads of things you can do to pass the time. Asking the passenger next to you about the travel experiences they've had is one of them. If you'd prefer a different sort of in-flight entertainment, you could always listen to an audio book.

How many direct and indirect flights does United Airlines fly from STL to ONT?

You'll have a lot of flexibility if you're thinking about flying with United Airlines from STL to ONT. At the moment, it has around 2 flights per day.

If I am not able to travel due to COVID-19, can I change my booking to a later date?

For more info about changing your flight to Ontario, CA (ONT-Los Angeles - Ontario Intl.), please visit our Customer Service Portal.

What is the best day to buy a plane ticket?

This just in! Airfares offered on Tuesdays tend to be the cheapest, according to flight demand on Travelocity in 2019. Wednesday and Friday prices are also good, but you may want to prepare your budget if booking on a Monday, as data shows the start of the week is when prices are generally at their highest.

What are the cheapest days to fly?

Frequent travelers may already know this, but earlier in the week can be the cheapest time to fly. In 2019, flights departing on a Tuesday were generally the cheapest of the week, whereas you may pay a premium for weekend flights when demand is usually high. On average, tickets were most expensive for Saturday departures, so if you need to fly out on a weekend, you might look for deals ahead of time.

How far in advance can you book a flight?

Trying to figure out how early you should book your flight? It's possible to start comparing international airfares on Travelocity up to 12 months in advance. However, it does depend on the carrier as not all airlines release their prices that far out. According to our 2019 flight demand trends, last minute planners can still bag a bargain with some of the cheapest fares appearing 1-2 weeks prior to their travel dates.

How can I save money on airline tickets?

We'll let you in on a secret...You can save big on flights if you mix and match your airlines and fare types. In fact, travelers who booked flights on Travelocity in 2019 saved nearly 50% when their return flights consisted of two different airlines or fare types.

*According to flight demand on Travelocity.com from January to December 2019. Savings are subject to change based on departure location, date and destination.

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*Price based on the lowest price found within past 24 hours and based upon one night stay for two adults over the next thirty days. Prices and availability subject to change. Additional terms may apply.