FlightRecord

New York (JFK) to San Juan (SJU): On-Time Performance

Data through July 2026

The calendar drives reliability on JFK–SJU. September 2024 flights landed on schedule 86% of the time, but July 2026 dropped to 52% — a gap of 35 points. Across the full period the route averages 72% on-time against a national 78%. Morning departures also hold up better than evening ones (76% vs 64%), which matters most in the rough months.

On-time
72%
arrived <15 min late
Avg delay
21 min
completed flights
Cancelled
1.9%
Flights/day
9.8
last 12 months
Duration
3h 60m
scheduled
Distance
1,598 mi

Best airline from JFK to SJU

3 airlines flew this route regularly between 2024-07 and 2026-07.

AirlineOn-timeAvg delayCancelledFlights
Delta Air Linesmost reliable79%14 min1.2%2,301
JetBlue Airways71%22 min2.2%4,755
Frontier Airlines65%30 min1.8%1,042

Monthly on-time trend

Monthly on-time percentage for JFK to SJU flights50%75%100%August 2024: 68% on-time (369 flights)68Aug 2024September 2024: 86% on-time (272 flights)86October 2024: 84% on-time (305 flights)84November 2024: 83% on-time (347 flights)83Nov 2024December 2024: 64% on-time (384 flights)64January 2025: 69% on-time (335 flights)69February 2025: 71% on-time (316 flights)71Feb 2025March 2025: 70% on-time (390 flights)70April 2025: 82% on-time (370 flights)82May 2025: 83% on-time (335 flights)83May 2025June 2025: 73% on-time (349 flights)73July 2025: 65% on-time (371 flights)65August 2025: 63% on-time (359 flights)63Aug 2025September 2025: 73% on-time (245 flights)73October 2025: 63% on-time (271 flights)63November 2025: 75% on-time (297 flights)75Nov 2025December 2025: 68% on-time (350 flights)68January 2026: 66% on-time (309 flights)66February 2026: 68% on-time (294 flights)68Feb 2026March 2026: 76% on-time (302 flights)76April 2026: 79% on-time (310 flights)79May 2026: 82% on-time (254 flights)82May 2026June 2026: 79% on-time (289 flights)79July 2026: 52% on-time (310 flights)52

Best time to fly from JFK to SJU

Aim for departures around 7 a.m. (83% on-time); avoid 6 p.m. departures (60%).

On-time percentage by scheduled departure hour, JFK to SJU5 a.m.: 83% on-time (462 flights)56 a.m.: 73% on-time (602 flights)67 a.m.: 83% on-time (202 flights)78 a.m.: 83% on-time (1,108 flights)89 a.m.: 74% on-time (206 flights)910 a.m.: 66% on-time (199 flights)1011 a.m.: 66% on-time (661 flights)1112 p.m.: 83% on-time (976 flights)121 p.m.: 63% on-time (323 flights)132 p.m.: 75% on-time (232 flights)143 p.m.: 70% on-time (343 flights)154 p.m.: 68% on-time (110 flights)165 p.m.: 66% on-time (360 flights)176 p.m.: 60% on-time (497 flights)187 p.m.: 67% on-time (668 flights)198 p.m.: 61% on-time (352 flights)209 p.m.: 63% on-time (433 flights)2110 p.m.: 66% on-time (327 flights)2211 p.m.: 70% on-time (37 flights)23scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday73%21 min
Tuesdaybest76%17 min
Wednesday74%18 min
Thursday69%22 min
Friday75%19 min
Saturday70%24 min
Sunday68%24 min

What causes delays on this route

Share of total delay minutes by cause, as reported by carriers to the US DOT.

  • Late-arriving aircraft32%
  • Airline operations40%
  • National airspace system26%
  • Weather2%
  • Security1%

Frequently asked questions

How often are flights from JFK to SJU delayed?
28% of JFK–SJU flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-07 and 2026-07. The average arrival delay across completed flights was 21 minutes.
Which airline is most reliable from JFK to SJU?
Delta Air Lines has the best on-time record on this route at 79%, based on 2,301 flights. 3 airlines flew JFK–SJU frequently enough to compare in this period.
What is the best time of day to fly from JFK to SJU?
Departures around 7 a.m. have the best record (83% on-time), while departures around 6 p.m. have the worst (60%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from JFK to SJU?
The scheduled JFK–SJU flight time averages 3h 60m over 1,598 miles. Actual arrival times vary — flights on this route land 15+ minutes late 28% of the time.
How often are JFK to SJU flights cancelled?
1.9% of scheduled flights on this route were cancelled between 2024-07 and 2026-07, slightly above the national rate of 1.6%.
What is the worst month to fly from JFK to SJU?
July 2026 was the roughest month in this dataset, with only 52% of arrivals on time. The best was September 2024 at 86%. If your dates are flexible, that 35-point gap is worth planning around.

Based on 8,098 flights, 2024-07–2026-07. Source: US DOT Bureau of Transportation Statistics. Updated 2026-09-28.