Airport month record
SJUJUL
Luis Munoz Marin International in July 2025
- Departures
- 3,415
- Month
- July 2025
- National, same month
- 71.1%
- Carriers
- 7
Historical statistics for July 2025, not live status or a forecast for this year’s July. For today’s conditions at SJU, see live FAA status.
SJU in July sits in the middle of the pack with a B. Close to three flights in four arrive on time by the DOT's definition, 4 points better than the national rate of 71.1%. The late ones land a little over an hour behind schedule. That rests on 3,415 flights, of which Southwest Airlines flew 489 at 82.6% on time.
Southwest Airlines is the most reliable of the three carriers covered here at 82.6% on time across 489 flights.
Key figures
On time
75.4%
Arrivals under 15 minutes late, of 3,344 completed departures
Avg delay
80 min
Across delayed arrivals only, not all flights
Cancelled
1.55%
Nationally in July: 2.45%
Whole year
77.8%
SJU across all twelve months
These figures cover 3,415 departures from Luis Munoz Marin International in July 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
July next to SJU's other months
Against SJU's own year, July ran 2 points worse than the twelve-month rate of 77.8%, which makes it number eight of twelve months, best first.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| July 2025 (this page) | 3,415 | 75.4% | 80 min | 1.55% | B |
| August 2025 | 2,975 | 70.9% | 80 min | 0.77% | C+ |
| September 2025 | 1,965 | 80.7% | 69 min | 0.00% | B+ |
| October 2025 | 2,186 | 79.1% | 68 min | 0.46% | B+ |
| November 2025 | 2,715 | 81.8% | 87 min | 1.07% | B |
| December 2025 | 3,393 | 78.4% | 79 min | 1.77% | B |
| January 2026 | 3,306 | 73.3% | 91 min | 7.96% | C− |
| February 2026 | 2,835 | 74.7% | 79 min | 3.17% | C− |
| March 2026 | 3,441 | 75.1% | 73 min | 2.06% | B |
| April 2026 | 3,190 | 78.4% | 68 min | 0.75% | B+ |
| May 2026 | 2,875 | 84.7% | 64 min | 0.21% | B+ |
| June 2026 | 3,095 | 83.1% | 76 min | 0.61% | B+ |
Departure window
The best time of day to leave SJU in July
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 23 points, against 20 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am685 flights87.1%
- 8am–11am316 flights84.3%
- 11am–2pm627 flights77.4%
- 2pm–5pm596 flights72.8%
- 5pm–8pm571 flights64.5%
- 8pm–5am620 flights68.0%
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 64.5% on time, against 87.1% 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. The 5am–8am window is the busiest, with 685 flights scheduled in it.
Across the week, Saturday is the strongest day at 79.1% on time and Sunday the weakest at 73.2%. 6 points is a smaller lever than departure hour, but it is free.
Carrier by carrier
Which airlines ran best at SJU in July
The choice of carrier is not cosmetic here. Southwest Airlines arrives on time 82.6% of the time; Frontier Airlines manages 62.8%. Sample sizes sit next to every figure, because a two-point gap across 504 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| JetBlue Airways | 1,090 | 71.0% | 77 min | 2.57% | C |
| Frontier Airlines | 504 | 62.8% | 93 min | 3.17% | D− |
| Southwest Airlines | 489 | 82.6% | 51 min | 0.00% | B+ |
| Spirit Airlinesthin sample | 362 | 81.5% | 52 min | 1.38% | B |
| American Airlinesthin sample | 338 | 73.8% | 94 min | 0.00% | C+ |
| United Airlinesthin sample | 318 | 78.5% | 96 min | 1.26% | B |
| Delta Air Linesthin sample | 314 | 90.1% | 99 min | 0.00% | A+ |
Frontier Airlines cancels 3.2% 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 SJU in July
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SJU to MCO · Orlando | 622 | 78.1% | 82 min | 0.48% | B+ |
| SJU to JFK · New York | 371 | 71.6% | 89 min | 3.77% | C− |
| SJU to FLL · Fort Lauderdalethin sample | 223 | 76.5% | 70 min | 0.90% | B+ |
| SJU to MIA · Miamithin sample | 216 | 71.6% | 89 min | 0.46% | C+ |
| SJU to ATL · Atlantathin sample | 207 | 86.7% | 71 min | 0.97% | A+ |
| SJU to EWR · Newarkthin sample | 199 | 61.7% | 112 min | 5.03% | D− |
| SJU to BOS · Bostonthin sample | 179 | 74.7% | 62 min | 2.79% | C |
| SJU to TPA · Tampathin sample | 145 | 73.6% | 55 min | 0.69% | C+ |
| SJU to BWI · Baltimorethin sample | 142 | 71.0% | 46 min | 1.41% | C |
| SJU to PHL · Philadelphiathin sample | 132 | 57.5% | 110 min | 3.79% | D− |
| SJU to ORD · Chicagothin sample | 126 | 85.6% | 55 min | 0.00% | A+ |
| SJU to IAH · Houstonthin sample | 111 | 92.7% | 49 min | 0.90% | A+ |
| SJU to DFW · Dallas-Fort Worththin sample | 97 | 85.3% | 107 min | 1.03% | A |
| SJU to BDL · Hartfordthin sample | 88 | 67.4% | 71 min | 2.27% | C |
| SJU to CLT · Charlottethin sample | 75 | 77.3% | 83 min | 0.00% | B+ |
| SJU to DTW · Detroitthin sample | 58 | 91.2% | 67 min | 1.72% | A |
| SJU to IAD · Washingtonthin sample | 53 | 78.8% | 80 min | 0.00% | B+ |
| SJU to RDU · Raleighthin sample | 48 | 83.3% | 35 min | 0.00% | B+ |
| SJU to STX · Christianstedthin sample | 40 | 67.5% | 88 min | 0.00% | C+ |
| SJU to STT · Charlotte Amaliethin sample | 39 | 69.2% | 113 min | 0.00% | C+ |
| SJU to CLE · Clevelandthin sample | 31 | 76.7% | 76 min | 3.23% | B− |
| SJU to HPN · White Plainsthin sample | 31 | 67.7% | 109 min | 0.00% | C+ |
| SJU to PVD · Providencethin sample | 31 | 60.0% | 64 min | 3.23% | D− |
| SJU to HOU · Houstonthin sample | 31 | 74.2% | 31 min | 0.00% | C+ |
| SJU to DCA · Washingtonthin sample | 31 | 51.6% | 64 min | 0.00% | F+ |
Delay causes
What held SJU up in July
One category carries most of the weight here. Late-arriving aircraft accounts for 55% of the 66,000 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.
- 55%Late-arriving aircraft
- 33%Carrier
- 12%National Airspace System
- 0%Extreme weather
55% 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 66,000 reported delay minutes here, that single category outweighs weather by 55 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 65,893 reported delay minutes.
Cancellations sit at 1.55% against a national 2.45%, which is ordinary. Diversions add another 0.53%.
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.5% of arrivals land a full hour or more behind schedule, against 12.1% 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.
What to do with this
Flying from SJU in July
For a July trip through SJU: expect 75.4% on time and 1.55% cancelled, going by July 2025. The 5am–8am window was the strongest part of the day.
Related
Where to go next
- Luis Munoz Marin International (SJU), the whole year
- SJU in August70.9%
- SJU in September80.7%
- SJU in October79.1%
- SJU in November81.8%
- SJU in December78.4%
- SJU in January73.3%
- SJU in February74.7%
- SJU in March75.1%
- SJU in April78.4%
- SJU in May84.7%
- SJU in June83.1%
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.