Route profile
SJU→PHL
Flight reliability, delays and best times to fly from San Juan to Philadelphia, 1,576 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 2% of comparable major US routes (4,598 compared)
Calculated from 5,116 flights. How this is calculated
SJU → PHL arrives on time 67.1% of the time; the return trip, PHL → SJU, arrives on time 63.5% of the time, a 3.6-point gap between the two directions of the same city pair.
SJU → PHL spends 28.5 minutes on the ground on a 1,576-mile trip: 17.4 minutes from pushback to wheels-up at SJU and 11.1 minutes from touchdown to gate at PHL.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
The airline matters unusually much on this route, a wider carrier-to-carrier gap than 96% of 2,692 comparable routes.
American Airlines arrived on time 77.2% of the time, against 55.6% for Frontier Airlines, flying the exact same route.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 2,692 in the comparison.
Why SJU → PHL flights are cancelled
July 2023 – July 2026
SJU → PHL cancelled 123 of 5,116 scheduled flights — about 1 in every 42. The reason filed most often was extreme weather, 61.8% of the cancellations coded on this route — about 1 in every 67 scheduled flights.
Share of cancellations
Of 123 cancelled departures carrying a reason code.
What each reason means
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
76 cancellations, 61.8% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
41 cancellations, 33.3% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
6 cancellations, 4.9% of the total.
A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.
0 cancellations, 0.0% of the total.
Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
123 coded cancellations were recorded on SJU → PHL; the section appears from 50.
When it goes wrong
July 2023 – July 2026
70 min late
against a median of 1 min early
SJU → PHL has an average that understates its risk: a typical arrival is 1 min early, but the worst tenth are 71 minutes worse than that. If the trip has something unmissable at the end of it, the median is the wrong number to plan against.
Percentiles over 5,116 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at PHL after arriving from SJU.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 48% | Likely to miss |
| 45 min | 32% | Likely to miss |
| 60 min | 22% | High risk |
| 90 min | 12% | Some risk |
| 120 min | 7.2% | Some risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 2.40% of the time and diverts 0.51% of the time, which a late arrival never shows up in.
Chance of missing is the share of 4,967 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 70 minutes late (90th-percentile gate arrival delay), over 5,116 operations.
Any other layover length: connection checker.
Best time to fly
SJU → PHL flights departing 5–9 AM arrived on time 85.7% of the time, against 56.5% for 3–6 PM departures, a gap of 29.2 percentage points.
By departure window
By departure hour
- 12 AM: 41.9% on time from 320 flights
- 1 AM: 64.7% on time from 470 flights
- 2 AM: 68.3% on time from 251 flights
- 3 AM to 4 AM: too few flights to score
- 5 AM: 87.9% on time from 240 flights
- 6 AM: 84.9% on time from 583 flights
- 7 AM: 87.6% on time from 202 flights
- 8 AM: 83.1% on time from 154 flights
- 9 AM: too few flights to score
- 10 AM: 55.1% on time from 230 flights
- 11 AM: 59.0% on time from 220 flights
- 12 PM: 68.8% on time from 262 flights
- 1 PM: 67.8% on time from 384 flights
- 2 PM: 74.9% on time from 428 flights
- 3 PM: 51.5% on time from 205 flights
- 4 PM: 56.3% on time from 198 flights
- 5 PM: 64.4% on time from 141 flights
- 6 PM to 7 PM: too few flights to score
- 8 PM: 47.8% on time from 188 flights
- 9 PM: 51.9% on time from 303 flights
- 10 PM to 11 PM: too few flights to score
Why SJU → PHL runs late
July 2023 – July 2026
the inbound aircraft was late, so this flight started late
crew, maintenance, boarding and fueling, all within the carrier’s control
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for SJU → PHL. Only delays of 15 minutes or more are attributed.
Late-arriving aircraft is the largest cause on SJU → PHL, at 43.7%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 85.7% of the time and 3–6 PM departures 56.5%.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| Frontier Airlines | 2,458 | 55.6% | 2.93% | 9 min | 16.9% |
| American Airlines | 1,665 | 77.2% | 1.32% | -7 min | 7.9% |
| Spirit Airlines | 865 | 76.1% | 3.01% | -8 min | 8.7% |
Frontier Airlines flew 49.3% of the 4,988 flights listed. Spirit Airlines cancelled 3.01% of its flights here against 1.32% for American Airlines.
American Airlines arrived on time 21.6 percentage points more often than Frontier Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
Weekly and seasonal patterns
By day of week
Saturday is historically the most reliable day and Monday the least, a gap of 4.8 percentage points.
By month
- Jan: 62.4%
- Feb: 68.3%
- Mar: 64.2%
- Apr: 76.4%
- May: 69.6%
- Jun: 70.6%
- Jul: 58.6%
- Aug: 60.5%
- Sep: 70.3%
- Oct: 75.3%
- Nov: 75.5%
- Dec: 61.1%
July is historically the weakest month and April the strongest, a spread of 17.8 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 65.0% from 124 flights
- August 2023: 67.5% from 124 flights
- September 2023: too few flights to score (89)
- October 2023: too few flights to score (96)
- November 2023: too few flights to score (116)
- December 2023: 59.8% from 132 flights
- January 2024: 60.4% from 161 flights
- February 2024: 59.2% from 126 flights
- March 2024: 47.5% from 124 flights
- April 2024: too few flights to score (113)
- May 2024: 38.2% from 129 flights
- June 2024: 51.9% from 132 flights
- July 2024: 43.2% from 136 flights
- August 2024: 51.2% from 128 flights
- September 2024: too few flights to score (58)
- October 2024: too few flights to score (64)
- November 2024: too few flights to score (102)
- December 2024: 66.7% from 165 flights
- January 2025: 68.2% from 164 flights
- February 2025: 75.9% from 147 flights
- March 2025: 78.7% from 157 flights
- April 2025: 85.4% from 165 flights
- May 2025: 73.9% from 165 flights
- June 2025: 68.5% from 133 flights
- July 2025: 57.5% from 132 flights
- August 2025: 62.7% from 129 flights
- September 2025: too few flights to score (65)
- October 2025: too few flights to score (93)
- November 2025: 76.2% from 125 flights
- December 2025: 56.3% from 164 flights
- January 2026: 59.0% from 194 flights
- February 2026: 68.5% from 175 flights
- March 2026: 63.4% from 203 flights
- April 2026: 80.6% from 224 flights
- May 2026: 85.6% from 197 flights
- June 2026: 85.8% from 180 flights
- July 2026: 66.7% from 185 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 70.8% against 72.2% in the 12 months before — broadly unchanged.
Data and methodology
Calculated by FlyerIntel from 5,116 SJU → PHL flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed