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$97+ Cheap flights from Ontario to Philadelphia (ONT - PHL)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/31. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — PHL
Oct 17 — Oct 241
Fri 10/17
Fri 10/24
1 adult, Economy
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Cheapflights Tip: The best prices from Ontario to Philadelphia are usually found in September or May, booked 56 days in advance, depart on a Tuesday or Wednesday and return on a Monday

Cheap flight deals from Ontario to Philadelphia

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Philadelphia (PHL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated September 17, 2025.

Round-trip from

$164
(CheapOair)

One-way from

$97
(CheapOair)

Popular in

January

Cheapest in

September

Average price

$348
From Ontario to Philadelphia
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One-way flight from Ontario to Philadelphia
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Highest demand for flights based on searches. 9% potential increase in price ($44 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($11 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find flight deals from Ontario to Philadelphia

Cheapest flights from Ontario to Philadelphia
Explore the most affordable flight options available from Ontario to Philadelphia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 17, 2025.

This CheapOair deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/136:53 amONT - PHL
1 stop18h 56mFrontier
Sat 11/156:19 amPHL - ONT
1 stop7h 51mFrontier
Deal found 9/15$164
This CheapOair deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/306:53 amONT - PHL
1 stop18h 56mFrontier
Sun 11/28:00 amPHL - ONT
1 stop10h 22mFrontier
Deal found 9/14$165
This CheapOair deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/248:34 amONT - PHL
1 stop14h 07mFrontier
Sun 11/28:00 amPHL - ONT
1 stop10h 22mFrontier
Deal found 9/16$166
This Frontier deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/612:05 pmONT - PHL
1 stop13h 44mFrontier
Thu 11/136:19 amPHL - ONT
1 stop7h 51mFrontier
Deal found 9/15$174
This Frontier deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/248:34 amONT - PHL
1 stop14h 07mFrontier
Thu 10/306:19 amPHL - ONT
1 stop7h 51mFrontier
Deal found 9/15$175
This CheapOair deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/248:59 pmONT - PHL
1 stop24h 58mFrontier
Thu 10/26:45 amPHL - ONT
1 stop28h 08mFrontier
Deal found 9/14$179
This CheapOair deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/18:59 pmONT - PHL
1 stop24h 58mFrontier
Wed 10/88:15 amPHL - ONT
1 stop26h 34mFrontier
Deal found 9/15$185
This CheapOair deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/94:17 pmONT - PHL
1 stop30h 24mFrontier
Sun 10/1211:30 amPHL - ONT
1 stop23h 19mFrontier
Deal found 9/15$186
This CheapOair deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/258:59 pmONT - PHL
1 stop24h 58mFrontier
Sat 9/276:45 amPHL - ONT
1 stop27h 38mFrontier
Deal found 9/15$194
This CheapOair deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/74:05 pmONT - PHL
1 stop9h 44mFrontier
Mon 11/106:19 amPHL - ONT
1 stop20h 31mFrontier
Deal found 9/15$198
This Frontier deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/112:05 pmONT - PHL
2 stops18h 08mFrontier
Fri 11/146:19 amPHL - ONT
1 stop7h 51mFrontier
Deal found 9/15$200
This Booking.com deal was found by Cheapflights users on 9/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/86:53 amONT - PHL
1 stop19h 26mFrontier
Thu 10/98:15 amPHL - ONT
1 stop10h 17mFrontier
Deal found 9/16$201

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Philadelphia that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 17, 2025.
Use the filters below to find and compare flights from Ontario to Philadelphia that are best for you.

Fly from

Ontario

Fly to

Philadelphia

Route

Depart

Return

Price

OntarioPhiladelphia

ONT - PHL

ONTPHL

Ontario

Fri 11/7

4:05 pm-4:49 am

1 stop9h 44m

Philadelphia

Sat 11/15

6:19 am-11:50 pm

1 stop20h 31m

$164

OntarioPhiladelphia

ONT - PHL

ONTPHL

Ontario

Wed 10/29

4:11 pm-5:42 am

1 stop10h 31m

Philadelphia

Wed 11/5

7:02 am-3:17 pm

1 stop11h 15m

$316

OntarioPhiladelphia

ONT - PHL

ONTPHL

Ontario

Wed 10/29

5:50 pm-8:41 am

2 stops11h 51m

Philadelphia

Wed 11/5

6:00 am-5:10 pm

2 stops14h 10m

$327

OntarioPhiladelphia

ONT - PHL

ONTPHL

Ontario

Tue 10/28

4:11 pm-5:42 am

1 stop10h 31m

Philadelphia

Sat 11/1

7:02 am-3:17 pm

1 stop11h 15m

$336

OntarioPhiladelphia

ONT - PHL

ONTPHL

Ontario

Wed 10/29

6:53 am-4:49 am

1 stop18h 56m

Philadelphia

Mon 11/3

6:35 pm-11:50 pm

2 stops32h 15m

$338

OntarioPhiladelphia

ONT - PHL

ONTPHL

Ontario

Tue 10/28

9:10 pm-9:40 am

2 stops9h 30m

Philadelphia

Mon 11/3

6:00 am-10:35 am

1 stop7h 35m

$339

OntarioPhiladelphia

ONT - PHL

ONTPHL

Ontario

Fri 11/7

4:11 pm-5:42 am

1 stop10h 31m

Philadelphia

Wed 11/12

7:02 am-3:17 pm

1 stop11h 15m

$357

OntarioPhiladelphia

ONT - PHL

ONTPHL

Ontario

Fri 12/12

4:15 pm-5:46 am

1 stop10h 31m

Philadelphia

Sat 12/13

7:06 am-3:21 pm

1 stop11h 15m

$359

OntarioPhiladelphia

ONT - PHL

ONTPHL

Ontario

Fri 12/5

6:00 am-5:54 pm

1 stop8h 54m

Philadelphia

Mon 12/8

7:06 am-3:21 pm

1 stop11h 15m

$364

OntarioPhiladelphia

ONT - PHL

ONTPHL

Ontario

Fri 12/12

4:49 pm-5:50 am

1 stop10h 01m

Philadelphia

Mon 12/15

6:47 pm-11:59 pm

1 stop8h 12m

$365

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 20 results
1
2

Best time to book a flight from Ontario to Philadelphia

Have a flexible travel schedule? Discover the best time to fly to Philadelphia from Ontario with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

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

Use this chart to determine the optimal time to book a round-trip flight from Ontario to Philadelphia. Price data was last updated on September 12, 2025.

The best time to book flights from Ontario to Philadelphia is 21 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from Ontario to Philadelphia?

Currently, August is the cheapest month in which you can book a flight from Ontario to Philadelphia (average of $236). Flying from Ontario to Philadelphia in March is currently the most expensive (average of $295). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from ONT to PHL?

Find hourly flight availability from Ontario to Philadelphia. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 17, 2025.

Unlike at noon, when flights are generally more expensive, you can save up to 29% on flights from Ontario to Philadelphia by exploring options for tickets in the afternoon.

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

Use this chart to determine the cheapest time to fly round-trip from Ontario to Philadelphia. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Ontario to Philadelphia flight should consider departing on Wednesday afternoons when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing Philadelphia

Get insights into the airlines that provide service to Philadelphia. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Philadelphia. Reviews last updated September 17, 2025.
Get a feel of what it's like to fly with Southwest, Delta, and United Airlines from Ontario to Philadelphia by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,242 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Southwest
8.0
Very good
4,242 reviews
Southwest
8.0
Very good
4,242 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Delta
8.0
Very good
7,961 reviews
Southwest
8.0
Very good
4,242 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
United Airlines
7.4
Good
8,926 reviews
Southwest
8.0
Very good
4,242 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,242 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Frontier
5.8
Fair
3,173 reviews
Southwest
8.0
Very good
4,242 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Philadelphia. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Ontario to Philadelphia?

    There are many flights that can get you from Ontario to Philadelphia in 9h 44m. Fly via Frontier, Hawaiian Airlines, or Delta to get the fastest option. Ontario and Philadelphia are separated by a distance of 2349 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines flying from Ontario to Philadelphia round-trip?

    Cheapflights users have booked flights from Ontario to Philadelphia round-trip from $88. Other airlines that can offer you cheap pricing are Frontier, from $151, and Delta, from $296. Spirit Airlines is 78% cheaper than the average price of flights available within the next 90 days to this destination.

  • Can I find deals for flights from Ontario to Philadelphia that include hotel bookings?

    Yes. In addition to deals on Ontario to Philadelphia flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Philadelphia?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Philadelphia.

  • Can I find deals for business class flights from Ontario to Philadelphia?

    Yes. Cheapflights offers flight deals from Ontario to Philadelphia by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Ontario to Philadelphia?

    Currently, August is the cheapest month in which you can book a flight from Ontario to Philadelphia (average of $236). Flying from Ontario to Philadelphia in March is currently the most expensive (average of $295). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Philadelphia?

Book flights to Philadelphia if you plan to visit one of these locations
Vineland
Wildwood
King of Prussia
Pottstown
Reading
Dewey Beach
Ephrata
Camden
Ocean City
Cherry Hill
Dover
Elkton
Essington
Willow Grove
Newark
Millville
Chester
Exton
Havre de Grace
Plymouth Meeting

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Alternative routes for Ontario to Philadelphia

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Top 6 airlines flying from Ontario to Philadelphia

Discover the top 6 airlines that operate flights from Ontario to Philadelphia. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$88Average$160FlexibilityNo cancel feeOn-time65%
FrontierCheapest$151Average$242FlexibilityNo cancel feeOn-time62%
DeltaCheapest$296Average$416FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$306Average$444FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$361Average$491FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$407Average$535FlexibilityNo cancel feeOn-time69%

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