$114 Cheap Flights from Ontario (ONT) to Philadelphia (PHL)

View $114 flight on Wed, Jan 7, 2026Opens in a new window

Popular airlines from Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL)

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Cheap Flights from Ontario to Philadelphia (ONT-PHL)

Prices were available within the past 7 days and start at $114 for one-way flights and $234 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Sat, Aug 16 - Thu, Aug 21
ONT
Ontario
PHL
Philadelphia
$234 Roundtrip, found 1 day ago
$234
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Sat, Aug 16 from Ontario to Philadelphia, returning Thu, Aug 21, priced at $234 found 1 day ago
American Airlines
Sat, Sep 20 - Wed, Sep 24
ONT
Ontario
PHL
Philadelphia
$238 Roundtrip, found 3 days ago
$238
Roundtrip
found 3 days ago
Select American Airlines flight, departing Sat, Sep 20 from Ontario to Philadelphia, returning Wed, Sep 24, priced at $238 found 3 days ago
Southwest Airlines
Tue, Sep 16 - Sat, Sep 20
ONT
Ontario
PHL
Philadelphia
$246 Roundtrip, found 6 days ago
$246
Roundtrip
found 6 days ago
Select Southwest Airlines flight, departing Tue, Sep 16 from Ontario to Philadelphia, returning Sat, Sep 20, priced at $246 found 6 days ago
Hawaiian Airlines
Tue, Oct 28 - Tue, Nov 11
ONT
Ontario
PHL
Philadelphia
$248 Roundtrip, found 3 days ago
$248
Roundtrip
found 3 days ago
Select Hawaiian Airlines flight, departing Tue, Oct 28 from Ontario to Philadelphia, returning Tue, Nov 11, priced at $248 found 3 days ago
American Airlines
Fri, Sep 12 - Mon, Sep 29
ONT
Ontario
PHL
Philadelphia
$249 Roundtrip, found 5 days ago
$249
Roundtrip
found 5 days ago
Select American Airlines flight, departing Fri, Sep 12 from Ontario to Philadelphia, returning Mon, Sep 29, priced at $249 found 5 days ago
American Airlines
Fri, Sep 26 - Tue, Sep 30
ONT
Ontario
PHL
Philadelphia
$251 Roundtrip, found 3 days ago
$251
Roundtrip
found 3 days ago
Select American Airlines flight, departing Fri, Sep 26 from Ontario to Philadelphia, returning Tue, Sep 30, priced at $251 found 3 days ago
United
Sat, Oct 25 - Wed, Oct 29
ONT
Ontario
PHL
Philadelphia
$256 Roundtrip, found 6 days ago
$256
Roundtrip
found 6 days ago
Select United flight, departing Sat, Oct 25 from Ontario to Philadelphia, returning Wed, Oct 29, priced at $256 found 6 days ago
Southwest Airlines
Mon, Sep 8 - Wed, Sep 10
ONT
Ontario
PHL
Philadelphia
$256 Roundtrip, found 4 days ago
$256
Roundtrip
found 4 days ago
Select Southwest Airlines flight, departing Mon, Sep 8 from Ontario to Philadelphia, returning Wed, Sep 10, priced at $256 found 4 days ago
American Airlines
Sat, Oct 4 - Mon, Oct 6
ONT
Ontario
PHL
Philadelphia
$262 Roundtrip, found 3 days ago
$262
Roundtrip
found 3 days ago
Select American Airlines flight, departing Sat, Oct 4 from Ontario to Philadelphia, returning Mon, Oct 6, priced at $262 found 3 days ago
Frontier Airlines
Sat, Aug 16 - Thu, Aug 21
ONT
Ontario
PHL
Philadelphia
$264 Roundtrip, found 1 day ago
$264
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Sat, Aug 16 from Ontario to Philadelphia, returning Thu, Aug 21, priced at $264 found 1 day ago

Find the cheapest month to fly from Ontario (ONT) to Philadelphia (PHL)

September is typically the cheapest month to fly

From $138 - $404 per traveler.

Graph displaying average flight prices per month

Flights from Ontario (ONT) to Philadelphia (PHL)
Origin airport
Los Angeles - Ontario Intl.
Destination airport
Philadelphia Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Hawaiian Airlines, JetBlue Airways, Southwest Airlines, United
Roundtrip price
$234
Distance
2349 mi

Ontario to Philadelphia Flights

The cheapest times to fly from Ontario to Philadelphia

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 Ontario to Philadelphia are during the month of August. You can find some of the cheapest flights from Ontario to Philadelphia with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Ontario to Philadelphia

Sunday is one of the best days to book for cheap flights from Ontario to Philadelphia: 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 Ontario to Philadelphia

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 Ontario to Philadelphia in 2025. You can also book with separate airlines for your outbound and return journeys, from $114 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 Ontario to Philadelphia 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 Ontario to Philadelphia 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 Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL) cost?
Grab a cheap one-way flight from $114 or cheap return flight from $234 from Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight offers on this route.
What is the cheapest month to fly from Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL)?
August is the least expensive month to fly from ONT to PHL. Timing your trip outside of the busy season is often the key to finding better deals on flights.
Which airlines fly direct from Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL)?
You can't fly nonstop from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Philadelphia Intl. Airport (PHL). However, you can easily journey to Philadelphia without any layovers by leaving from Los Angeles Intl. Airport (LAX).
What is the cheapest airline that flies from Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL)?
To find the cheapest airline that'll fly you from ONT to PHL, use Expedia's filter tool. Customize your search based on what matters most to you, such as preferred carriers and cabin class. You can then sort your results by "Price (lowest to highest)" to list the most affordable options first.
How many flights per day from Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL)?
You'll need to book a flight with a layover when traveling from Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL). Direct flights don't operate daily on this route. However, simply filter your search to include one or more stops to find an option that works for you.
What day of the week has the most flights from ONT to PHL?
Usually you'll find the greatest selection of flight options on a Friday. Tuesdays are often the quietest.* However, this can vary based on the airline, time of year and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL)?
To arrive at Philadelphia Intl. Airport (PHL) on schedule, select a flight that leaves Los Angeles - Ontario Intl. Airport (ONT) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this time.**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 Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL) last-minute?
Last-minute fares from ONT to PHL are typically more expensive. To lock in the cheapest rates, start searching for flights well ahead of time. That being said, if you can play around with your travel dates, you may land a cheap fare right before you leave.
Is it cheaper to book an ONT to PHL flight and hotel package?
Compared with arranging flights and hotels separately, booking an ONT to PHL flight and hotel package with Expedia could result in significant savings. Better yet, having everything in one easy place takes the hassle out of planning your trip. Simply pick your flights and choose from our wide range of hotels, then customize your trip with other add-ons like car rentals and activities.
Can I cancel or change the date of my flight from Los Angeles - Ontario Intl. Airport (ONT) to Philadelphia Intl. Airport (PHL)?
If you booked your ONT to PHL flight within the last 24 hours, you may be able to modify or cancel it at no cost. Depending on the airline and the ticket type you purchased, additional charges may apply for changes beyond that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, go to our Customer Service portal if you want more information.

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*Available to One Key members.