Frontier's UpFront Plus seats guarantee an empty middle seat for extra comfort.
Frontier offers Zone 1 boarding with carry-on purchase or special fare bundles.

Most accurate provider | CheapOair 3 stars |
|---|---|
Most trusted provider | CheapOair 3 stars |
Round-trip from | $107 (CheapOair) |
One-way from | $59 (CheapOair) |
Popular in | March |
Cheapest in | October |
Average price | $251 |
Good round-trip deal | $217 or less |
Good one-way deal | $143 or less |
Fly from
Fly to
Route
Depart
Return
Price
ChicagoPhiladelphia
MDW - PHL
MDWPHL
Chicago Midway
Thu 1/15
9:40 am-12:35 pm
Nonstop1h 55m
Philadelphia
Sun 1/18
5:40 am-7:00 am
Nonstop2h 20m
ChicagoPhiladelphia
MDW - PHL
MDWPHL
Chicago Midway
Wed 12/31
6:08 pm-11:17 pm
1 stop4h 09m
Philadelphia
Thu 1/1
6:00 am-8:49 am
1 stop3h 49m
ChicagoPhiladelphia
ORD - PHL
ORDPHL
Chicago O'Hare Intl
Thu 1/22
8:56 am-12:07 pm
Nonstop2h 11m
Philadelphia
Mon 1/26
1:10 pm-2:40 pm
Nonstop2h 30m
ChicagoPhiladelphia
MDW - PHL
MDWPHL
Chicago Midway
Sat 1/10
5:30 pm-8:20 pm
Nonstop1h 50m
Philadelphia
Thu 1/15
1:40 pm-2:55 pm
Nonstop2h 15m
ChicagoPhiladelphia
ORD - PHL
ORDPHL
Chicago O'Hare Intl
Fri 2/6
2:30 pm-5:34 pm
Nonstop2h 04m
Philadelphia
Sun 2/8
10:10 am-11:38 am
Nonstop2h 28m
ChicagoPhiladelphia
ORD - PHL
ORDPHL
Chicago O'Hare Intl
Fri 1/16
8:56 am-12:07 pm
Nonstop2h 11m
Philadelphia
Mon 1/19
10:10 am-11:38 am
Nonstop2h 28m
ChicagoPhiladelphia
MDW - PHL
MDWPHL
Chicago Midway
Thu 1/15
9:32 am-4:28 pm
1 stop5h 56m
Philadelphia
Sun 1/18
5:40 am-10:27 am
1 stop5h 47m
ChicagoPhiladelphia
ORD - PHL
ORDPHL
Chicago O'Hare Intl
Tue 1/6
5:30 am-1:24 pm
1 stop6h 54m
Philadelphia
Sun 1/11
6:00 am-9:41 am
1 stop4h 41m
ChicagoPhiladelphia
MDW - PHL
MDWPHL
Chicago Midway
Fri 1/30
6:35 pm-11:13 pm
1 stop3h 38m
Philadelphia
Mon 2/2
9:40 am-12:46 pm
1 stop4h 06m
ChicagoPhiladelphia
ORD - PHL
ORDPHL
Chicago O'Hare Intl
Sun 1/11
5:30 am-1:24 pm
1 stop6h 54m
Philadelphia
Mon 1/12
9:40 am-1:08 pm
1 stop4h 28m
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*2 stars | |
| Price Accuracy2 stars | Trust Score*3 stars |
Booking 85 days in advance of your planned departure date is, on average, the best time to get cheap flights from Chicago to Philadelphia. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
Currently, January is the cheapest month in which you can book a flight from Chicago to Philadelphia (average of $36). Flying from Chicago to Philadelphia in July is currently the most expensive (average of $104). 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.
It’s typically best to fly out from Chicago to Philadelphia in the evening. Doing so could potentially save you 27% on the flight price compared to flying in the afternoon, which is usually more expensive.
Travelers seeking maximum savings on their Chicago to Philadelphia flight should consider departing on Monday 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.
The most flights from CHI to PHL are scheduled on a Wednesday (38 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (24 on average).
About 19% of weekly flights between Chicago and Philadelphia have experienced delays in the past year, with the average delay time being 138 minutes.
Historically, flights departing in the morning are less likely to be delayed, whereas flights leaving in the evening tend to experience delays more often.
Tuesday tends to have the lowest number of delays on this route, whereas Thursday has historically faced a higher average of delays compared to other days of the week.
Over the last year, United Airlines have had the lowest number of delays on this route, with just 17% of flights being delayed.
Boarding
Entertainment
Comfort
Crew
Overall
Food
Reviews
Thomas,Dec 2025
SEA - DEN
Boarding
Entertainment
Comfort
Crew
Overall
Food
Reviews
Thomas,Dec 2025
SEA - DEN
Boarding
Entertainment
Comfort
Crew
Overall
Food
Reviews
Thomas,Dec 2025
SEA - DEN
Boarding
Entertainment
Comfort
Crew
Overall
Food
Reviews
Thomas,Dec 2025
SEA - DEN
Boarding
Entertainment
Comfort
Crew
Overall
Food
Reviews
Thomas,Dec 2025
SEA - DEN
Boarding
Entertainment
Comfort
Crew
Overall
Food
Reviews
Thomas,Dec 2025
SEA - DEN
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$63 | Average$260 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$78 | Average$166 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$108 | Average$477 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$149 | Average$326 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$160 | Average$302 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$177 | Average$305 | FlexibilityNo cancel fee | On-time63% |