Airport month record

PHLSEP

Philadelphia International in September 2025

Departures: 8,225
Month: September 2025
National, same month: 83.4%
Carriers: 10

Historical statistics for September 2025, not live status or a forecast for this year’s September. For today’s conditions at PHL, see live FAA status.

PHL in September lands a B+, about a point worse than the national rate of 83.4%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 8,225 flights, of which Delta Air Lines flew 530 at 90.0% on time.

Delta Air Lines is the most reliable of the five carriers covered here at 90.0% on time across 530 flights.

On time

82.0%

Arrivals under 15 minutes late, of 8,157 completed departures

Avg delay

67 min

Across delayed arrivals only, not all flights

Cancelled

0.53%

Nationally in September: 0.51%

Whole year

75.7%

PHL across all twelve months

These figures cover 8,225 departures from Philadelphia International in September 2025. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.

Against the year

September next to PHL's other months

Against PHL's own year, September ran 6 points better than the twelve-month rate of 75.7%, which makes it the best of the twelve months in the data. Cancellations were unusually low for PHL in September, at 0.53% against 2.64% across the year. Either side of it, August ran 72.2% on time and October 77.5%, so a trip moved by a few weeks would have landed in a worse stretch.

PHL month by month
Month	Flights	On time	Avg delay	Cancelled	Grade
July 2025	9,013	65.1%	103 min	5.25%	C−
August 2025	9,120	72.2%	79 min	1.30%	C
September 2025 (this page)	8,225	82.0%	67 min	0.53%	B+
October 2025	9,306	77.5%	72 min	0.44%	B+
November 2025	7,499	77.8%	80 min	2.00%	B
December 2025	7,468	65.3%	80 min	2.36%	C
January 2026	7,049	75.5%	84 min	7.86%	B−
February 2026	6,686	80.0%	70 min	6.09%	B−
March 2026	7,778	76.7%	86 min	3.15%	B−
April 2026	8,692	80.8%	73 min	0.68%	B+
May 2026	9,251	80.7%	74 min	1.09%	B
June 2026	9,707	74.4%	85 min	2.73%	C

Departure window

The best time of day to leave PHL in September

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 22 points, against 11 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am938 flights93.1%
8am–11am2,043 flights89.3%
11am–2pm1,314 flights83.9%
2pm–5pm1,381 flights79.0%
5pm–8pm2,128 flights70.9%
8pm–5am421 flights80.5%

Scale runs 60% to 100%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 93.1% of the time, against 70.9% for the evening window. That is 22 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 2,128 flights scheduled in it.

Across the week, Tuesday is the strongest day at 86.5% on time and Thursday the weakest at 72.3%. 14 points is a smaller lever than departure hour, but it is free.

Carrier by carrier

Which airlines ran best at PHL in September

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 90.0% of the time; American Airlines manages 79.3%. Sample sizes sit next to every figure, because a two-point gap across 4,224 flights means less than a ten-point one.

Carriers at PHL in September 2025
Airline	Flights	On time	Avg delay	Cancelled	Grade
American Airlines	4,224	79.3%	63 min	0.57%	B+
PSA Airlines	1,239	87.0%	82 min	0.65%	A+
Frontier Airlines	638	80.7%	82 min	0.00%	B+
Delta Air Lines	530	90.0%	86 min	0.00%	A+
Southwest Airlines	437	84.6%	47 min	0.00%	B+
United Airlinesthin sample	352	85.9%	54 min	0.57%	A+
Republic Airwaysthin sample	350	84.6%	63 min	1.71%	B
Spirit Airlinesthin sample	243	85.8%	58 min	0.82%	A+
JetBlue Airwaysthin sample	152	65.1%	90 min	1.32%	C
Alaska Airlinesthin sample	60	80.0%	54 min	0.00%	B+

Delta leads American by 11 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Route by route

Busiest routes out of PHL in September

Routes from PHL in September 2025
Route	Flights	On time	Avg delay	Cancelled	Grade
PHL to ATL · Atlanta	436	88.0%	47 min	0.46%	A+
PHL to BOS · Boston	427	60.7%	67 min	2.34%	D
PHL to ORD · Chicago	412	77.2%	63 min	0.24%	B+
PHL to MCO · Orlando	403	80.3%	76 min	0.25%	B+
PHL to CLT · Charlottethin sample	291	89.0%	76 min	0.34%	A+
PHL to DEN · Denverthin sample	283	84.0%	68 min	0.35%	B+
PHL to DTW · Detroitthin sample	267	88.7%	71 min	0.75%	A+
PHL to DFW · Dallas-Fort Worththin sample	258	80.8%	59 min	1.94%	B
PHL to BNA · Nashvillethin sample	236	82.1%	52 min	0.00%	B+
PHL to MIA · Miamithin sample	217	80.4%	46 min	0.92%	B+
PHL to FLL · Fort Lauderdalethin sample	213	83.7%	79 min	0.47%	B+
PHL to LAX · Los Angelesthin sample	211	87.1%	48 min	0.47%	A+
PHL to RDU · Raleighthin sample	207	82.1%	64 min	0.00%	B+
PHL to TPA · Tampathin sample	172	83.0%	76 min	0.58%	B+
PHL to SFO · San Franciscothin sample	167	87.3%	61 min	0.00%	A+
PHL to MSP · Minneapolisthin sample	162	82.1%	124 min	0.00%	B+
PHL to PHX · Phoenixthin sample	160	85.7%	54 min	1.88%	A
PHL to MDW · Chicagothin sample	159	84.3%	43 min	0.00%	B+
PHL to IAH · Houstonthin sample	137	81.0%	75 min	0.00%	B+
PHL to STL · St. Louisthin sample	132	78.8%	56 min	0.00%	B+
PHL to CMH · Columbusthin sample	125	83.9%	67 min	0.80%	B+
PHL to LAS · Las Vegasthin sample	125	78.4%	49 min	0.00%	B+
PHL to SEA · Seattlethin sample	122	80.3%	57 min	0.00%	B+
PHL to PIT · Pittsburghthin sample	122	77.0%	58 min	0.00%	B+
PHL to JAX · Jacksonvillethin sample	117	82.9%	81 min	0.00%	B+

Delay causes

What held PHL up in September

Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 99,000 reported delay minutes.

Late-arriving aircraft
42%
Carrier
34%
National Airspace System
22%
Extreme weather
3%
Security
0%

42% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 99,000 reported delay minutes here, that single category outweighs weather by 16 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 98,601 reported delay minutes.

Cancellations are rare at 0.53%, below the national 0.51% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.

6.7% of arrivals land an hour or more late, close to the national 5.4%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.

What to do with this

Flying from PHL in September

For a September trip through PHL: this is one of the better months to be flying from here, 82.0% on time with 0.53% cancelled. That is a base rate for the month as a whole; a single storm can still spoil a particular day.

Philadelphia International (PHL), the whole year
PHL in July65.1%
PHL in August72.2%
PHL in October77.5%
PHL in November77.8%
PHL in December65.3%
PHL in January75.5%
PHL in February80.0%
PHL in March76.7%
PHL in April80.8%
PHL in May80.7%
PHL in June74.4%

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures