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

Start packing your suitcase, because round-trip journeys from PHL to Los Angeles - Ontario Intl. Airport (ONT) start from . That's based on fares listed within the last 7 days on Expedia for flights departing within the next year. Prices can rise quickly, so book today to secure the best deal. Prices and availability are subject to change. Additional terms apply.

Every air carrier has its own set of terms and conditions. If you do decide to cancel, follow the instructions on our Customer Service Portal.

Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you're searching for Philadelphia Airport to Ontario Airport flights, you'll see a "no change fees" filter for you to select.

You'll be cruising at altitude for a while, as the flight distance between Philadelphia and Ontario is 3,800 kilometres. Put together a playlist of your favourite podcasts before you leave home to stay entertained during your flight.

Unfortunately, there are no airlines that directly fly between PHL and Ontario Airport. You'll have to book a flight with one or more stops.

Last-minute planners can sometimes nab a bargain, with some of the cheapest airfares from PHL to Los Angeles - Ontario Intl. Airport (ONT) arising a few weeks before the departure date. If you'd rather plan ahead of time, Expedia compares and updates all the best flight deals continually — as early as a year in advance in some cases. It depends on the carrier though, as not every airline advertises prices so far in advance.