Philadelphia, PA · departure reliability
PHL
Philadelphia International
- Departures
- 98,786
- Period
- June 2025 to May 2026
- Carriers
- 10
- US rank
- #24 by volume
Philadelphia
Philadelphia International sits in the middle of the pack with a C. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.4%. The late ones land a little over an hour behind schedule. That rests on 98,786 flights, of which Delta Air Lines flew 6,458 at 82.3% on time.
Delta Air Lines is the most reliable of the ten carriers covered here at 82.3% on time across 6,458 flights.
Key figures
On time
74.9%
Departures arriving under 15 minutes late at their destination
Avg delay
81 min
Across delayed flights only
Cancelled
2.68%
National rate is 1.80%
Best carrier
Delta
82.3% on time here
These figures cover 99,000 flights between June 2025 and May 2026. Beyond the headline rate, 10.4% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Which airlines run best out of PHL
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 82.3% of the time; Alaska Airlines manages 64.3%. Sample sizes sit next to every figure, because a two-point gap across 675 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| American Airlines | 45,933 | 74.9% | 80 min | 2.36% | C |
| PSA Airlines | 16,135 | 74.2% | 91 min | 4.32% | C− |
| Frontier Airlines | 9,066 | 68.2% | 85 min | 2.71% | C |
| Republic Airways | 6,948 | 81.1% | 74 min | 3.18% | B− |
| Delta Air Lines | 6,458 | 82.3% | 87 min | 2.18% | B |
| Southwest Airlines | 5,065 | 72.9% | 61 min | 1.01% | C |
| United Airlines | 4,242 | 79.0% | 87 min | 1.27% | B |
| Spirit Airlines | 2,587 | 71.8% | 72 min | 4.17% | C− |
| JetBlue Airways | 1,575 | 70.7% | 78 min | 2.22% | C |
| Alaska Airlines | 675 | 64.3% | 56 min | 1.48% | D |
PSA Airlines cancels 4.3% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Route by route
Busiest routes out of PHL
Route-level records vary far more than the airport average. These are the 25 busiest departures from PHL, each with its own on-time rate against the airport-wide 74.9%.
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| PHL to ATL · Atlanta | 5,685 | 77.9% | 69 min | 2.76% | B |
| PHL to MCO · Orlando | 5,347 | 71.5% | 82 min | 2.49% | C |
| PHL to BOS · Boston | 4,909 | 74.7% | 79 min | 2.97% | C |
| PHL to ORD · Chicago | 4,812 | 72.3% | 99 min | 3.10% | C− |
| PHL to CLT · Charlotte | 3,513 | 79.9% | 83 min | 2.48% | B |
| PHL to DFW · Dallas-Fort Worth | 3,385 | 76.6% | 91 min | 3.81% | B− |
| PHL to FLL · Fort Lauderdale | 3,291 | 72.2% | 76 min | 3.01% | C− |
| PHL to MIA · Miami | 3,100 | 76.6% | 84 min | 1.94% | B |
| PHL to DEN · Denver | 2,995 | 75.7% | 76 min | 1.27% | B |
| PHL to DTW · Detroit | 2,953 | 79.8% | 96 min | 2.78% | B |
| PHL to BNA · Nashville | 2,784 | 74.8% | 76 min | 2.01% | C |
| PHL to TPA · Tampa | 2,586 | 73.0% | 83 min | 2.05% | C |
| PHL to RDU · Raleigh | 2,521 | 74.3% | 80 min | 2.42% | C |
| PHL to LAX · Los Angeles | 2,449 | 77.6% | 65 min | 1.39% | B |
| PHL to PHX · Phoenix | 2,311 | 79.9% | 73 min | 1.77% | B |
| PHL to MSP · Minneapolis | 1,991 | 77.1% | 112 min | 3.42% | B− |
| PHL to SFO · San Francisco | 1,915 | 74.7% | 74 min | 1.31% | C |
| PHL to SJU · San Juan | 1,831 | 62.1% | 78 min | 3.33% | D− |
| PHL to IAH · Houston | 1,803 | 79.5% | 81 min | 2.05% | B |
| PHL to STL · St. Louis | 1,576 | 75.8% | 73 min | 1.46% | B |
| PHL to JAX · Jacksonville | 1,543 | 75.1% | 85 min | 2.72% | B |
| PHL to PBI · West Palm Beach | 1,538 | 73.3% | 81 min | 2.80% | C |
| PHL to MDW · Chicago | 1,531 | 72.4% | 70 min | 1.50% | C |
| PHL to IND · Indianapolis | 1,527 | 75.2% | 70 min | 3.67% | B− |
| PHL to LAS · Las Vegas | 1,495 | 75.8% | 77 min | 1.94% | B |
Departure window
The best time of day to leave PHL
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 21 points, against 18 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am12,615 flights85.6%
- 8am–11am23,149 flights83.4%
- 11am–2pm14,533 flights77.2%
- 2pm–5pm15,576 flights70.5%
- 5pm–8pm23,624 flights64.6%
- 8pm–5am9,289 flights68.8%
Scale runs 55% to 90%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 64.6% on time, against 85.6% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in.
Across the year
When PHL runs late
PHL's year swings by 17 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
July is the worst month at 65.1% on time, 17 points below September, the best at 82.0%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck.
Across the week, Wednesday is the strongest day at 80.0% on time and Sunday the weakest at 70.0%. 10 points is a smaller lever than departure hour, but it is free.
Delay causes
Why PHL gets delayed
One category carries most of the weight here. Late-arriving aircraft accounts for 44% of the 1.95 million delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 44%Late-arriving aircraft
- 30%Carrier
- 21%National Airspace System
- 5%Extreme weather
- 0%Security
44% 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 1.95 million reported delay minutes here, that single category outweighs weather by 9 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 practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 85.6% on time here.
Cancellations run at 2.68%, against 1.80% nationally. That is about one flight in 40 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.4% of arrivals land a full hour or more behind schedule, against 8.2% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
98,786 flights sit behind these numbers, which is a large enough sample that the headline rate is not moving on noise. Where a sub-group falls below 30 flights the site shows a dash instead of a percentage.
What to do with this
Flying out of PHL
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 82.0% on time and July 65.1%, a swing of 17 points. If the dates move at all, move them out of July before you think about anything else.
Common questions
PHL delay questions
How often is Philadelphia (PHL) delayed?
About one flight in four arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 25.1% of the 98,786 flights in this analysis, against 22.6% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on Philadelphia (PHL)?
Delta Air Lines leads at 82.3% on time across 6,458 flights. Alaska Airlines is at the other end on 64.3%, a gap of 18 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on Philadelphia (PHL)?
The 5am–8am departure window is the strongest at 85.6% on time. The 5pm–8pm window is the weakest at 64.6%, 21 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are July delays on Philadelphia (PHL)?
July is the weakest month at 65.1% on time, compared with 82.0% in September. Across the year that is 17 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- PHL to ATL — Atlanta77.9%
- PHL to MCO — Orlando71.5%
- PHL to BOS — Boston74.7%
- PHL to ORD — Chicago72.3%
- American Airlines on-time record74.9%
- PSA Airlines on-time record74.2%
- Frontier Airlines on-time record68.2%
- Republic Airways on-time record81.1%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, June 2025 to May 2026. Updated monthly. How this data is collected.