£138 Cheap Flights from Philadelphia (PHL) to Ontario Intl. Airport (ONT)

View £138 flight on Wed, 10 Jun 2026Opens in a new window

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

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Cheap Flights from Philadelphia (PHL) to Ontario Intl. Airport (ONT)

Prices were available within the past 7 days and start at £138 for one-way flights and £265 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Sat, 30 May - Wed, 10 Jun
PHL
Philadelphia
ONT
Ontario
£265 Return, found 3 hours ago
£265
Return
found 3 hours ago
Select Alaska Airlines flight, departing Sat, 30 May from Philadelphia to Ontario, returning Wed, 10 Jun, priced at £265 found 3 hours ago
Alaska Airlines
Mon, 1 Jun - Wed, 10 Jun
PHL
Philadelphia
ONT
Ontario
£306 Return, found 3 hours ago
£306
Return
found 3 hours ago
Select Alaska Airlines flight, departing Mon, 1 Jun from Philadelphia to Ontario, returning Wed, 10 Jun, priced at £306 found 3 hours ago
Alaska Airlines
Sat, 30 May - Thu, 11 Jun
PHL
Philadelphia
ONT
Ontario
£312 Return, found 3 hours ago
£312
Return
found 3 hours ago
Select Alaska Airlines flight, departing Sat, 30 May from Philadelphia to Ontario, returning Thu, 11 Jun, priced at £312 found 3 hours ago
Alaska Airlines
Mon, 1 Jun - Thu, 11 Jun
PHL
Philadelphia
ONT
Ontario
£352 Return, found 3 hours ago
£352
Return
found 3 hours ago
Select Alaska Airlines flight, departing Mon, 1 Jun from Philadelphia to Ontario, returning Thu, 11 Jun, priced at £352 found 3 hours ago
Alaska Airlines
Sat, 23 May - Tue, 26 May
PHL
Philadelphia
ONT
Ontario
£359 Return, found 4 days ago
£359
Return
found 4 days ago
Select Alaska Airlines flight, departing Sat, 23 May from Philadelphia to Ontario, returning Tue, 26 May, priced at £359 found 4 days ago
American Airlines
Fri, 15 May - Fri, 22 May
PHL
Philadelphia
ONT
Ontario
£365 Return, found 3 days ago
£365
Return
found 3 days ago
Select American Airlines flight, departing Fri, 15 May from Philadelphia to Ontario, returning Fri, 22 May, priced at £365 found 3 days ago
American Airlines
Fri, 15 May - Fri, 22 May
PHL
Philadelphia
ONT
Ontario
£369 Return, found 3 days ago
£369
Return
found 3 days ago
Select American Airlines flight, departing Fri, 15 May from Philadelphia to Ontario, returning Fri, 22 May, priced at £369 found 3 days ago
American Airlines
Fri, 15 May - Fri, 22 May
PHL
Philadelphia
ONT
Ontario
£387 Return, found 3 days ago
£387
Return
found 3 days ago
Select American Airlines flight, departing Fri, 15 May from Philadelphia to Ontario, returning Fri, 22 May, priced at £387 found 3 days ago
Delta
Fri, 15 May - Fri, 22 May
PHL
Philadelphia
ONT
Ontario
£391 Return, found 3 days ago
£391
Return
found 3 days ago
Select Delta flight, departing Fri, 15 May from Philadelphia to Ontario, returning Fri, 22 May, priced at £391 found 3 days ago
United
Sun, 31 May - Fri, 5 Jun
PHL
Philadelphia
ONT
Ontario
£419 Return, found 3 hours ago
£419
Return
found 3 hours ago
Select United flight, departing Sun, 31 May from Philadelphia to Ontario, returning Fri, 5 Jun, priced at £419 found 3 hours ago

Alternative airports near Ontario

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Los Angeles - Ontario Intl. ONT. Cheapest and Closest option available. Average driving time to city centre is 8 minutes. Flights from £442
ONT
Los Angeles - Ontario Intl.
CheapestClosest
Average driving time to city centre8 min
Flights from £442

Frequently asked questions

How do I find cheap flights from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.)?
To find a cheap flight from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best time to fly from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.)?
The best time to fly is usually mid-week (Tuesday or Wednesday) and during early morning hours as flights tend to be cheaper, less crowded, and generally more on-time. Avoid major holidays and peak vacation seasons for smoother travel. Combining off-peak days and hours often gives the best combination of cost, comfort, and convenience.
How many flights per day from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.)?
There are approximately 73 connecting flights per day from Philadelphia International Airport (PHL) to Los Angeles - Ontario International Airport (ONT). Some common connection points include Seattle - Tacoma International Airport (SEA), Denver International Airport (DEN), and O'Hare International Airport (ORD).
What is the earliest flight from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.)?
The earliest flight from Philadelphia International Airport (PHL) to Los Angeles - Ontario International Airport (ONT) typically departs at approximately 5:00 AM local time, operated by American Airlines. This is a seasonal service active in January. An early departure like this can help maximise your time at your destination. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What day of the week has the most flights from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.)?
If you're flying from Philadelphia International Airport (PHL) to Los Angeles - Ontario International Airport (ONT), you'll typically find the most flights on a Thursday, with around 45 flights available. This gives you plenty of options for your travel plans. Flight schedules are consistent throughout the week, with Thursday having only slightly more flights than other days. Major airlines on this route include American Airlines, United Airlines, and Southwest Airlines.
What are the most popular departure times for flights from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.)?
The most popular departure times for flights from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.) are in the early morning, from 6am to 9am. About 32% of passengers prefer this time. Many major carriers, including American Airlines, Delta Air Lines and United Airlines, offer flights during this window. This timing works well because you can get an early start to your travel day and arrive at your destination with plenty of time left.
How long does it take to fly from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.)?
Flying from PHL to ONT with a connection usually takes about 7 hours 50 minutes, traveling roughly 2,350 miles. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.)?
Select the "Business class" and "First class" filters when looking for PHL to ONT flights on Expedia. This is the easiest way to compare prices, routes and flight times for your trip.
How do I earn miles on a Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.) flight with Expedia?
It's easy to earn miles on a Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia. *Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for Ontario from Philadelphia Intl. (PHL)?
If you're planning to travel to Ontario from Philadelphia Intl. (PHL), you can fly directly into Los Angeles - Ontario Intl. (ONT) Some flights may connect through major hubs like O'Hare Intl. (ORD), Seattle - Tacoma Intl. (SEA), Midway Intl. (MDW) before reaching Ontario. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.) at the last minute?
Typically, booking a last minute flight from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.) flight and hotel package?
Securing a Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.) flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.)?
If you booked your Philadelphia, PA (PHL-Philadelphia Intl.) to Ontario, CA (ONT-Los Angeles - Ontario Intl.) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Philadelphia Intl.
Destination airport
Ontario Intl. Airport
Return price
£265
Distance
3759 km
Average flight time
9 hours 22 mins

Book with confidence

Compare flights from Philadelphia to Ontario Intl. Airport easily and book with confidence

For travelling on business or for pleasure, Expedia makes it easy to book your flights from Philadelphia to Ontario Intl. Airport. Operating between them flights per day, 20 airlines cover the route. And fly direct, getting you to Ontario Intl. Airport in just hours. If you have a preferred carrier, use our advanced search tool to find the right flight from Philadelphia Intl. to Ontario Intl. Airport.  

To make things even better, in the advanced search, you can also choose to fly economy, premium economy, business or first class, select your maximum number of stops, and pick your preferred departure and arrival time. You can also opt for refundable and direct flights. 

Grab a great deal on your flight from Philadelphia Intl. (PHL) to Ontario Intl. Airport (ONT)

The easiest way to view the best deals on flights from Philadelphia to Ontario Intl. Airport today is to enter your travel dates and hit search. From here, you can sort your results by price to see the cheapest flights first. Right now, return flights from Philadelphia Intl. to Ontario Intl. Airport start at just £265 and range up to £419.  

To find an even better deal, try  

  • being flexible on your dates – midweek flights can be cheaper
  • looking for other airports near Philadelphia and Ontario Intl. Airport
  • booking your flight during May, the cheapest month on this route
  • varying your flight times – early morning and late at night are sometimes cheaper 

Why you should book your Philadelphia to Ontario Intl. Airport flight with Expedia!

We cater for all flight types, cabin classes and airlines. So whether you’re booking flights from Philadelphia Intl. to Ontario Intl. Airport for a budget break or a business trip with a bit of pleasure thrown in, we make it easy to secure the seat that’s right for you.  

Thanks to our supersized inventory that offers great choice all in one place, you know you’ll get a great deal with Expedia. Especially if you bundle your flight together with your hotel, you will unlock amazing savings. For added peace of mind, you can choose flexible bookings or filter to find refundable options, so you won’t pay a fee to change your flight.  

Compare flights from Philadelphia to Ontario Intl. Airport easily and book with confidence

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