ONT - PHL

$66 Find Cheap Flights from Ontario to Philadelphia

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ontario to Philadelphia departing on 12/25. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Philadelphia

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Philadelphia.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Philadelphia.
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Everything you should know

Cheapest round-trip
$134
Overall average: $470
Frontier
Fri 12/5Mon 12/8
ONT - PHL • 1 stop
Cheapest one-way
$66
Typical prices: $236-$320
Frontier
Thu 12/25
ONT - PHL • 1 stop
When to book
2 weeks
in advance
Our data shows that travelers who book at least 2 weeks in advance save around 23% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
February
Cheapest • 25% price drop
December
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Ontario to Philadelphia (ONT-PHL)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to Philadelphia that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Ontario to Philadelphia

Fri, Dec 5 - Mon, Dec 8
Frontier Logo
3:20 pm - 5:31 amONT-PHL
11h 11m1 stop
Frontier Logo
6:15 am - 4:33 pmPHL-ONT
13h 18m1 stop
$134Frontier
Find Deal
Wed, Dec 17 - Sat, Jan 3
Frontier Logo
6:15 am - 5:40 amONT-PHL
20h 25m1 stop
Frontier Logo
7:10 am - 11:21 pmPHL-ONT
19h 11m1 stop
$137Frontier
Find Deal
Sun, Dec 7 - Fri, Dec 12
Frontier Logo
2:59 pm - 2:39 pmONT-PHL
20h 40m1 stop
Frontier Logo
8:36 pm - 2:25 pmPHL-ONT
20h 49m1 stop
$138Frontier
Find Deal
Fri, Dec 5 - Sat, Jan 3
Frontier Logo
3:20 pm - 5:31 amONT-PHL
11h 11m1 stop
Frontier Logo
10:01 pm - 7:24 amPHL-ONT
12h 23m1 stop
$141Frontier
Find Deal
Thu, Jan 8 - Sun, Jan 11
Frontier Logo
6:56 pm - 11:33 amONT-PHL
13h 37m1 stop
Frontier Logo
9:42 am - 6:03 pmPHL-ONT
11h 21m1 stop
$142Frontier
Find Deal
Mon, Dec 22 - Thu, Jan 1
Frontier Logo
6:00 am - 5:40 amONT-PHL
20h 40m1 stop
Frontier Logo
7:10 am - 9:17 pmPHL-ONT
17h 07m1 stop
$144Frontier
Find Deal
Fri, Dec 5 - Sat, Jan 3
Frontier Logo
3:20 pm - 5:31 amONT-PHL
11h 11m1 stop
Frontier Logo
7:10 am - 11:21 pmPHL-ONT
19h 11m1 stop
$145Frontier
Find Deal
Fri, Dec 5 - Thu, Jan 8
Frontier Logo
3:20 pm - 5:31 amONT-PHL
11h 11m1 stop
Frontier Logo
9:42 am - 6:03 pmPHL-ONT
11h 21m1 stop
$146Frontier
Find Deal
Thu, Nov 27 - Mon, Dec 8
Frontier Logo
12:58 am - 4:45 amONT-PHL
24h 47m1 stop
Frontier Logo
6:15 am - 4:33 pmPHL-ONT
13h 18m1 stop
$149Frontier
Find Deal
Sat, Dec 27 - Sat, Jan 3
Frontier Logo
5:16 pm - 5:31 amONT-PHL
33h 15m2 stops
Frontier Logo
7:10 am - 11:21 pmPHL-ONT
19h 11m1 stop
$156Frontier
Find Deal
Booking Insights

KAYAK's insights & trends for Ontario to Philadelphia flights

Get data-powered insights and trends into flights from Ontario to Philadelphia to help you find the cheapest flights, the best time to fly and much more.

What’s the cheapest day of the week to fly from Ontario to Philadelphia?

The average price of all round-trip flights from Ontario to Philadelphia clicked on KAYAK for each day over the last 12 months.

For Ontario to Philadelphia, Tuesday is the cheapest day to fly on average and Sunday is the most expensive. Flying from Philadelphia back to Ontario, the best deals are generally found on Monday, with Saturday being the most expensive.

What is the cheapest month to fly from Ontario to Philadelphia?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ontario to Philadelphia, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Ontario to Philadelphia is February, where tickets cost $306 (return) on average. On the other hand, the most expensive months are October and December, where the average cost of round-trip tickets is $482 and $470 respectively.

How far in advance should I book a flight from Ontario to Philadelphia?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Ontario to Philadelphia, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Ontario to Philadelphia, you should book around 2 weeks before departure, which saves you about 23% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 17 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$66
Best time to beat the crowds but there is an average 10% increase in price.
Most popular time to fly with an average 15% increase in price.
Flight from Ontario to Philadelphia

When to book flights from Ontario to Philadelphia

Are your dates flexible? Find out the best times to travel from Ontario to Philadelphia based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Ontario to Philadelphia

  • Which amenities can I enjoy if I upgrade to business class on flights from Ontario to Philadelphia?

    On-board amenities on the Ontario to Philadelphia flight route can vary depending on the airline. Some exclusive amenities when flying business class include additional luggage allowance, in-flight entertainment, complimentary snacks and drinks, a lie-flat seat, a blanket, and additional legroom. So, upgrading to business class is a great decision on this long-haul flight.

  • What are the common layovers on flights from Ontario to Philadelphia?

    After booking cheap flights from Ontario to Philadelphia, expect a stop or more depending on your airline's flight route. The layover city and duration also vary among airlines. The common layovers are major cities, including Phoenix, Chicago, Charlotte, Dallas, Houston, Denver, Las Vegas, Houston, Salt Lake City, Austin, Atlanta, Oakland, Dallas, Austin, San Francisco, Portland, Orlando, and Seattle.

  • What is the carry-on and checked luggage allowance in economy class for flights from Ontario to Philadelphia?

    The carry-on and checked luggage allowances depend on the airline. If you book Frontier Airlines, your carry-on should be 24 x 16 x 10 inches at most. You’re allowed to bring an additional bag weighing at most 50 lb. If you book American Airlines, your carry-on should be a maximum of 22 x 14 x 9 inches, and another bag with a maximum weight of 50 lb is allowed.

  • What’s the most convenient way to travel from Philadelphia International Airport to downtown Philadelphia?

    The airport line train is a reliable way to travel to downtown Philadelphia from PHL airport. These trains depart hourly, and the trip takes about 24 minutes. Another option is the Line 37 bus that gets to the city in approximately 39 minutes. You can also rent a car at the airport terminal and drive to your destination.

  • What is the cheapest flight from Ontario to Philadelphia?

    In the last 3 days, the lowest price for a flight from Ontario to Philadelphia was $66 for a one-way ticket and $134 for a round-trip.

  • Do I need a passport to fly between Ontario and Philadelphia?

    No, a passport isn't needed to fly from Ontario to Philadelphia. However, local authorities might ask for an official ID.

  • Which aircraft models fly most regularly from Ontario to Philadelphia?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Ontario to Philadelphia?

    Star Alliance, SkyTeam, and oneworld are the airline alliances operating flights between Ontario and Philadelphia, with Star Alliance being the most commonly used for this route.

  • What is the most popular layover when flying to Philadelphia from Ontario?

    Phoenix is the most popular layover city among KAYAK users traveling from Ontario to Philadelphia.

  • Which is the best airline for flights from Ontario to Philadelphia, Southwest or Delta?

    The two airlines most popular with KAYAK users for flights from Ontario to Philadelphia are Southwest and Delta. With an average price for the route of $496 and an overall rating of 8.0, Southwest is the most popular choice. Delta is also a great choice for the route, with an average price of $414 and an overall rating of 7.9.

  • How does KAYAK find such low prices on flights from Ontario to Philadelphia?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to Philadelphia.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to Philadelphia?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Philadelphia from Ontario is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Ontario to Philadelphia?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Philadelphia with an airline and back to Ontario with another airline. Booking your flights between Ontario and PHL can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to Philadelphia?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Philadelphia from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Ontario to Philadelphia

  • Frontier Airlines offers an eco-friendly journey on cheap flights from Ontario (ONT) to Philadelphia (PHL). This airline ensures environmental sustainability by using fuel-efficient aircraft and reducing carbon emissions during operations.
  • Ontario International Airport (ONT) is a hub for West Coast Air. At the same time, Philadelphia International Airport (PHL) is a hub for American Airlines. This airport is a gateway for transatlantic and European destinations.
  • The Line 61 bus offers a convenient journey from downtown Ontario to ONT airport. These buses arrive at the airport in about 10 minutes and depart every 30 minutes. You can also take a shuttle or a taxi to arrive at the airport in approximately 5 minutes.
  • You can book Aer Lingus from Ontario to Philadelphia if you need a special meal. This airline offers a wide range of special meals, including gluten-free, vegetarian, and diabetic. You need to order up to 24 hours before departure, but for kosher meals, you must request 48 hours prior to your flight.
  • PHL airport serves several nearby cities. After arriving, you can visit Darby to the north, Woodbury to the west, Springfield to the northwest, Chester to the southwest, and Camden to the northeast. You can rent a car at the airport and drive to your destination.

Reviews of the top 5 airlines serving from Ontario to Philadelphia

 
See real verified KAYAK customer reviews for airlines flying from Ontario to Philadelphia. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Ontario to Philadelphia? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4235 reviews
8.6Crew
8.0Comfort
7.5Entertainment
8.1Boarding
7.0Food
Airline reviews

Crew could have been friendlier, maybe I'm spoiled by SW crews. In flight wifi was good. Would be nice to have more food offerings on a 4 plus hour flight

10.0 ExcellentMichael, Nov 2025LAX - BWI
Read more Southwest reviews

Crew could have been friendlier, maybe I'm spoiled by SW crews. In flight wifi was good. Would be nice to have more food offerings on a 4 plus hour flight

Ever since Southwest starting charging for bags, passengers don't want to pay to check their bags, so the gate agents have to beg people to check their roller bags now because there's "not enough space". This was a terrible business move by Southwest.

Sacrament staff are always polite and helpful. Airport is easy to maneuver and boarding is straightforward.

As always, the entire Southwest experience was wonderful, from online booking to flight to baggage retrieval. Very grateful.

The weather could have been better. There was a 40 minute ATC delay in SFO because of marine fog and a micro cell storm delayed landing and take-off at Nashville. The gate was changed 5 minutes from boarding from gate B3 to gate C23 at Nashville airport.

The cabin was quiet for the redeye flight. The area was clean. The staff was great. The 787 Max was in good condition. Drawbacks were that the seat widths were tight for some passengers. The seat padding was at best average and for a long flight uncomfortable.

Delayed flight. Nicest crew member was a SW pilot flying seated next to me who kindly move to seat the final passenger. Flight extra delayed. My cup of refreshment of ginger ale was so packed with ice it was literally 2 sips.

No trays in our seats, we sat in first row, purchased a business class fare. Had to hold our drinks and snack in our hands. No plugs for our cell phones. Had to pay for it a drink cocktail each. Seats so uncomfortable.

Flight wasn’t even full, but too many carry-ons caused us to run out of bin space. New bag fee has folks who would usually check their bags carrying on. Watching Southwest morph into Spirit/Frontier is so sad to watch

Southwest is Southwest. No frills. If you're luck enough to get a happy crew (we did), then it makes for a nicer flight.

Staff were friendly and happy. Delta could make sure passengers that don't have the app know of changes. Without Kayak I would not have known about the change of gate or the delay. Kayak was faster to notify me.

The flight used a B767 with a very old interior from before 2014. The entertainment system did not work at all during the flight despite attempts to reset the system. It was like they flew this route just to be competitive.

Delayed flight (1hour) plus a long layover after an overnight flight with no backup plane available.

Flight delayed for two and half hours and then canceled altogether due to mechanical issues. No mechanic onsite to fix so had to send one from LAX.

Delayed due to thunderstorms and no in-flight service due to rough weather — both of which are out of Delta’s control. Flight was good overall.

My husband upgraded our seats and I don't know if it was due to the type of planet was or if they didn't upgrade our seats. We were supposed to be in I believe comfort seats and they were just as tight as any other seat- no leg room and we are very tall people but at least it wasn't extremely cold. My husband did put in a complaint about our seating because he paid extra and if we would have known that the space and the tightness would have been the same, we just would have gotten the emergency row emergency row seats that we normally get. We love Delta but both our flights coming home we're not good. Oh I forgot to mention that on our flight to Hawaii our luggage wheels got broke and we had to purse new luggage on vacation then we never had this problem so we didn't know protocol and reported it after we got home only for them to tell is we only had 24hrs to report the damage. Not sure what was going on with Delta this vacation trip.

Crew was excellent. Comfort seats not as nice as other kinds of planes.

It was a great flight and the stewards and stewardess were all kind and accommodating!! The seats were comfortable and entertainment screen excellent!

There are 4 flights in consecutive gates with about the same departure time. Two flights were boarding at the same time. One was delayed or boarding would be happening at the same time. I am not sure what Delta and LAX need to do to have a better layout at the end of Terminal 2

There was a security issue at the airport and we were unable to land. We circled endlessly and then landed at another airfield for fuel. We then circled the airport again, almost landed but didn’t fully touch down before circling again. I am thankful to the crew for keeping us safe- the issue was the airline and staff at the airport getting us seats on our connecting flights. That part was hours of searching for someone and getting in double my steps.

Older aircraft, no meal, only food was for purchase. Not impressed United.

Not pleasant trip cross country when the entertainment and WiFi system not working. No entertainment for entirety of route. Staff was rather nonchalant in that they dismissed the problem due to age of plane. It would have been nice to know this up front so I could have come prepared to read or download movies before boarding Coincidentally or not, there was a similar issue with the entertainment system on my previous flight I took on my fist leg of the trip. There are no seat TVs, so you must rely on the app when it works. United can do better. Also, what use it it to pay for boarding group 2 when half of the passengers are in the same line as you?

Premium Plus is a really good idea for longer flights

The flight attendants were great, I joked with one I can’t remember her name, a blond, really sweet. I thought it was run well very professional. This was great i survived Spirit, I know for which I speak.

I was in first class. The outlets at my seat did not work. The plane was shabby and run down. I had prepurchsed a day subscription for internet that was not redeemable. I had to repurchase the internet for my flight and then it didn’t work anyway. Quite disappointed in what was supposed to be the launch of a great vacation.

I understand stuff happens, but plane failures are likely due to lack of maintenance. Additionally, air conditioning wasn't working, no snack/drink service, no WiFi. Fortunately, the crew was communicative and light-hearted. United grabbed another plane and we were able to get to our destination.

Stuck on tarmac for two hours plus a 5.5 hour flight. Rude flight attendant. And no meals, not even for purchase!

I learned that seating towards the end of plane that a line forms for the restroom and people use your chair as a hand railing, bumping your seat consistently. I was seated in the aisle. I think that next time if I am towards the back row I would want to sit in the middle or window seat.

United sent me a mileage plus number last year but that number is invalid so I can’t use it to check into flights or collect mileage. There is human to speak about the problem, only computers who keep asking me if I am using the correct email. It’s so frustrating and I cannot resolve it.

Not a great experience. We paid for the upgrade for premium economy seats and seated ourselves in very comfortable seats. Someone came along with the same seat on their boarding pass. The aircraft had been changed and as a result we were booted out and sent further back to small uncomfortable seats. After complaining we were moved to emergency row seats, which gave us more leg room but the seats don’t recline. For people in our 70’s we found having to sit upright from California to NJ very uncomfortable. Not sure why they chose to move senior citizens instead of the two people that were allowed to take the more comfortable seats. Not happy.

the trip to madrid was uncomfortable with my legs touching the seat in front of me

Very crowded flight but what can you expect these days?? Crew was accommodating.

The seats in economy were appeared to be quite thin and lack sufficient cushioning to be comfortable. Perhaps it was my seating position but the plane seemed notably load.

Internet was a bit expensive and did not work ask that week otherwise a good flight

The flight had a delay that made me being in a real rush to take the second flight. The delay was almost for 2 hours. They moved us from gate to gate in 4 times. Once I arrived to Philadelphia, I got to run thorough all the airport, as the train was already closed by that time. So I got sick with asthma for all the running I had to do. And I was the last one to board, when it was almost closed. So irresponsable with the people

The plane was probably full boarding was easy. We were able to check our carry-on luggage for free. It was a return flight through Philly to LA. Never saw a stewardess do a demonstration of emergency Procedures. I think my flight was pretty full

Overall, a good experience. The food, however, was subpar. The breakfast was a joke.

I was late from Jacksonville, FL but the limited interaction I had with the Philly crew was great.

The delays and cancellations kept me stuck in Miami for an additional 24 hours, and the whole thing seemed extremely disorganized

Everything was great except British airways lost our luggage that was gate checked all the way through to Italy. No one knows currently where one is and the other one may be in route to Amsterdam to meet us but not sure. If you can Hale’s it would be awesome. The website is not helpful.

When I wanted to check in 3 hours prior to boarding time, the employees mentioned “a little over an hour delay” so I waited for an hour then I went to go look for food in the terminal and most people from that flight were in the same area looking for food. Finally I decided after food to check to see if it’s anytime closer and now it’s 2 mins until boarding closes?! What are you kidding me? I didn’t receive anything via sms about boarding now nor via email or on the intercom. I luckily made it through, barely, and then there’s no room for my carry on mind you I’m in the very first row so I had to place my purse in one further row back and my carry on sections down. Not sure who pays for better seats to get your stuff placed all over the plane but that was the worst experience I’ve ever had flying with anyone.

This airline sucks. They offer low rates then charge you for everything, the app does not work well, the seats are the most uncomfortable. Maintenance issues on the flight, and you still have to sit through their credit card commercials. People are nice enough but does not make up for overall poor experience.

Cancelled flight after I arrived at airport after 75 min drive and parking. Next flight was 4 days in the future. Had to scramble and buy a much more expensive flight on another carrier.

I liked the turn-style feature at gate 209B at LAX. Very efficient process. The gate staff also made several, clearly directed announcements so I felt very informed.

The seats were awful, hard plastic covered in sheet vinyl. The airline tries to scam you into paying extra to get seat together when the flight wasn’t full. They were going to separate a family with young children but my wife who had a row to herself gave up her seat so the young mom could be with her young boys. I’m never giving this airline my money again.

It was a short flight so no food or entertainment….

Frontier had yet another flight cancellation. Have never made a complete round trip with this airline without at least one leg getting cancelled. Miserable flights - dirty, uncomfortable planes that apparently always have issues since I've had multiple delays and cancellations with them.

Flight was delayed 3 times, would have been nice to have received text message instead of email notifications. Frontier app wasn’t even updated accordingly, no gate number disclosed. No agent at front desk of gate to inform of delay. Very confused and left if the dark

They changed the timing , first delayed by 4 hours then went back to 40 mins late, we had to run back to airport to not miss our flight. This is ridiculous

No frills for sure. No gate announcements about flight delay, not even water to drink on the flight.

Everything you need to know for your flight from Ontario to Philadelphia

Information on your arrival and departure airports