MIA to SJU flight delays
Miami, FL (MIA) San Juan, PR (SJU) · 1,045 miles
2,636 flights · January 2025 – August 2026 · US Bureau of Transportation Statistics
74.66%
Arrived on time
Within 15 minutes of schedule
0.95%
Cancelled
Share of scheduled flights
76 min
When late, late by
Average across delayed arrivals
20 min
Delay per flight
Averaged over every flight flown
What the record says about this route
Which airline you fly changes the odds here. American Airlines arrived on time 21 points more often than Spirit Airlines over the same period on the same route — same airports, same weather, same air traffic control. A gap that survives all of that is about how the two airlines are run.
The season swings this route hard. In May it ran 22.9 points more punctual than in July — a difference bigger than the one between the best and worst airlines on most routes. If the date is flexible, it is worth more than the carrier.
Flights from Miami to San Juan run late more often than the average route, though not severely.
Which airline should you fly on this route?
Over January 2025 – August 2026, American Airlines arrived on time most often on MIA to SJU. Spirit Airlines was late most often. Flights ran closest to schedule in May and worst in July.
Every airline on MIA to SJU
Ranked by how many flights each one operated. A carrier with fewer than 100 flights in the period is listed but not graded.
| Airline | Flights | On time | Cancelled | Avg delay | Grade |
|---|---|---|---|---|---|
| American Airlines | 2,078 | 76.8% | 0.53% | 71 min | C |
| Frontier Airlines | 379 | 71.51% | 1.85% | 84 min | D |
| Spirit Airlines | 179 | 55.81% | 3.91% | 96 min | F |
Month by month
Share of flights that arrived within 15 minutes of schedule, by month flown.
The return leg
SJU to MIA San Juan back to Miami 77.73% on time COther routes from Miami
Common questions
Are flights from Miami to San Juan usually delayed?
74.66% of flights on the MIA to SJU route arrived within 15 minutes of schedule, so roughly 3 in every ten arrived late. That is about the same as the average route in this record.
Which airline is most on time from Miami to San Juan?
American Airlines, at 76.8% on time across 2,078 flights. The least punctual on the route was Spirit Airlines at 55.81%.
How often are MIA to SJU flights cancelled?
0.95% of scheduled flights did not operate — about 10 in every thousand. That is in the normal range.
What is the best month to fly Miami to San Juan?
May, when 85.5% of flights arrived on time. The worst was July at 62.6%.
When MIA to SJU flights are late, how late are they?
About 76 minutes on average across the flights that arrived more than 15 minutes behind schedule.
What these figures do and do not tell you
Everything on this page is counted from the flights that actually operated on MIA to SJU during January 2025 – August 2026, as reported by the airlines to the US Bureau of Transportation Statistics. "On time" is the federal definition: arriving at the gate within 15 minutes of the scheduled time.
A route's record is a description of the past, not a forecast. Weather, air traffic control and the aircraft's earlier flights that day drive most delays, and none of them are predictable from a historical rate. What the record does tell you is whether this route runs late more often than others, and which carrier on it has the better history — which is the part you can actually act on when you book.
Cancellations are counted separately from delays because they are a different problem for a traveller: a late flight still gets you there. How the grade is calculated →