$157 Cheap Flights from Greenville (GSP) to Ontario (ONT)

View $157 flight on Wed, Jul 2, 2025Opens in a new window

Popular airlines from Greenville-Spartanburg Intl. Airport (GSP) to Los Angeles - Ontario Intl. Airport (ONT)

Find available prices by choosing your travel dates.

Cheap Flights from Greenville to Ontario (GSP-ONT)

Prices were available within the past 7 days and start at $157 for one-way flights and $313 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Wed, Jul 2 - Sat, Jul 5
GSP
Greenville
ONT
Ontario
$313 Roundtrip, found 9 hours ago
$313
Roundtrip
found 9 hours ago
Select Delta flight, departing Wed, Jul 2 from Greenville to Ontario, returning Sat, Jul 5, priced at $313 found 9 hours ago
American Airlines
Tue, May 20 - Sun, May 25
GSP
Greenville
ONT
Ontario
$313 Roundtrip, found 15 hours ago
$313
Roundtrip
found 15 hours ago
Select American Airlines flight, departing Tue, May 20 from Greenville to Ontario, returning Sun, May 25, priced at $313 found 15 hours ago
United
Sat, May 24 - Wed, May 28
GSP
Greenville
ONT
Ontario
$318 Roundtrip, found 12 hours ago
$318
Roundtrip
found 12 hours ago
Select United flight, departing Sat, May 24 from Greenville to Ontario, returning Wed, May 28, priced at $318 found 12 hours ago
United
Sat, May 24 - Wed, May 28
GSP
Greenville
ONT
Ontario
$318 Roundtrip, found 12 hours ago
$318
Roundtrip
found 12 hours ago
Select United flight, departing Sat, May 24 from Greenville to Ontario, returning Wed, May 28, priced at $318 found 12 hours ago
United
Tue, May 20 - Sun, May 25
GSP
Greenville
ONT
Ontario
$323 Roundtrip, found 15 hours ago
$323
Roundtrip
found 15 hours ago
Select United flight, departing Tue, May 20 from Greenville to Ontario, returning Sun, May 25, priced at $323 found 15 hours ago
United
Tue, May 20 - Sat, May 24
GSP
Greenville
ONT
Ontario
$323 Roundtrip, found 15 hours ago
$323
Roundtrip
found 15 hours ago
Select United flight, departing Tue, May 20 from Greenville to Ontario, returning Sat, May 24, priced at $323 found 15 hours ago
Delta
Fri, Jul 4 - Tue, Jul 22
GSP
Greenville
ONT
Ontario
$326 Roundtrip, found 7 hours ago
$326
Roundtrip
found 7 hours ago
Select Delta flight, departing Fri, Jul 4 from Greenville to Ontario, returning Tue, Jul 22, priced at $326 found 7 hours ago
United
Sat, May 24 - Wed, May 28
GSP
Greenville
ONT
Ontario
$331 Roundtrip, found 12 hours ago
$331
Roundtrip
found 12 hours ago
Select United flight, departing Sat, May 24 from Greenville to Ontario, returning Wed, May 28, priced at $331 found 12 hours ago
Southwest Airlines
Sat, Sep 6 - Tue, Sep 9
GSP
Greenville
ONT
Ontario
$339 Roundtrip, found 2 days ago
$339
Roundtrip
found 2 days ago
Select Southwest Airlines flight, departing Sat, Sep 6 from Greenville to Ontario, returning Tue, Sep 9, priced at $339 found 2 days ago
Alaska Airlines
Wed, Jun 4 - Tue, Jun 10
GSP
Greenville
ONT
Ontario
$449 Roundtrip, found 1 day ago
$449
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Wed, Jun 4 from Greenville to Ontario, returning Tue, Jun 10, priced at $449 found 1 day ago
Flights from Greenville (GSP) to Ontario (ONT)
Origin airport
Greenville-Spartanburg Intl.
Destination airport
Los Angeles - Ontario Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Southwest Airlines, United
Roundtrip price
$312
Distance
2004 mi

Greenville to Ontario Flights

The cheapest times to fly from Greenville to Ontario

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Greenville to Ontario are during the month of July. You can find some of the cheapest flights from Greenville to Ontario with Expedia's search tool and vast selection of airlines.

The best time to book a flight from Greenville to Ontario

Sunday is one of the best days to book for cheap flights from Greenville to Ontario: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

How to find cheap round-trip tickets from Greenville to Ontario

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Greenville to Ontario in 2025. You can also book with separate airlines for your outbound and return journeys, from $157 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Greenville to Ontario flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

You could also save big by booking one of Expedia's vacation packages. Bundling together your Greenville to Ontario airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

*Terms apply.

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

Frequently asked questions

How much does a flight from Greenville-Spartanburg Intl. Airport (GSP) to Los Angeles - Ontario Intl. Airport (ONT) cost?
Discover the latest flight deals from GSP to ONT by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from GSP to ONT?
The cheapest flights from GSP to ONT are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from GSP to ONT?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that’ll take you from GSP to ONT. Sort your results by “Price (lowest to highest)” to snap up a great deal.
How many flights per day from Greenville-Spartanburg Intl. Airport (GSP) to Los Angeles - Ontario Intl. Airport (ONT)?
Nonstop flights from Greenville-Spartanburg Intl. Airport (GSP) to Los Angeles - Ontario Intl. Airport (ONT) aren’t available daily, so you’ll need to take a flight with a layover. Explore your options with Expedia’s filters. Enter your travel details and select either “1 Stop” or “2+ Stops.”
What day of the week has the most flights from GSP to ONT?
You’ll usually find Tuesday the quietest day for flights, while Fridays tend to be the busiest.* However this can vary from season to season and during peak travel times or public holidays.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Greenville-Spartanburg Intl. Airport (GSP) to Los Angeles - Ontario Intl. Airport (ONT)?
Opt for a flight from Greenville-Spartanburg Intl. Airport (GSP) to Los Angeles - Ontario Intl. Airport (ONT) that leaves before 3 PM to reduce the risk of cancellations. Departures after this hour have a 22% higher chance of being canceled, on average.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.
Is it cheaper to buy a plane ticket from Greenville-Spartanburg Intl. Airport (GSP) to Los Angeles - Ontario Intl. Airport (ONT) last-minute?
Last-minute fares from GSP to ONT are generally more expensive. For the best prices, start looking for flights ahead of time. That said, if you can play around with your travel dates, it’s possible to score a cheap ticket just before your departure.
Is it cheaper to book a GSP to ONT flight and hotel package?
You’ll generally save money by securing a GSP to ONT flight and hotel package compared to booking separately. In fact, travelers could save hundreds of dollars by bundling with Expedia. And it’s simple to manage everything in one place. After selecting your preferred accommodations and flights, consider adding extras including car rentals, tours and activities.
Can I cancel or change the date of my flight from Greenville-Spartanburg Intl. Airport (GSP) to Los Angeles - Ontario Intl. Airport (ONT)?
If you reserved your GSP to ONT flight within the last 24 hours, you may be able to cancel or modify it at no cost. Depending on the airline and the fare type you purchased, additional charges may apply for changes after that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal if you’d like more information.

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*Available to One Key members.