MIA to SJU flight delays

MIA SJU Miami to Luis Munoz Marin · 1,045 miles

8,271 flights were scheduled from MIA to SJU over July 2023 through June 2026. Of the 8,194 that made the trip, 76.2% reached the gate less than 15 minutes behind schedule. These are arrival figures: “on time” means the flight reached the gate less than 15 minutes behind schedule. Arrivals are what decide whether you make the connection, so route and airline pages are scored on them rather than on pushback.

Data through June 2026 · Bureau of Transportation Statistics

The route in brief

Flights in the window
8,271
Arrived on time
76.2%
Cancelled
0.8%
Scheduled distance
1,045 miles

Cancellations are counted against everything scheduled. Diverted flights are counted with them rather than as very late arrivals, which is why the on-time share and the cancellation rate do not add up to everything that happened.

Airline by airline

Airlines with at least 100 flights on MIA–SJU, busiest first. Same route, same weather, same air traffic — which makes this the fairest comparison on the site.

Airline Arrived on time Typical delay Cancelled Flights
American Airlines 76.4% 68 min 0.4% 5,861
Frontier Airlines 76.9% 89 min 1.8% 1,469
Spirit Airlines 73.2% 86 min 1.7% 916

Month by month

July was the month to avoid on MIA–SJU: 68.8% of flights arrived on time, against 85.2% in October. Each bar pools three years of that calendar month.

Share of flights that arrived on time, by calendar month. Best month in green, worst in amber. The hairline sits at the overall rate, 76.2%.
Arrival on-time share, MIA to SJU, by calendar month
Month Share flights that arrived on time Flights
January 71.3% 713
February 80.4% 643
March 70.8% 768
April 77.3% 722
May 80.4% 703
June 75% 681
July 68.8% 745
August 69.5% 720
September 83.7% 575
October 85.2% 607
November 79.8% 659
December 75.7% 735

Both ends of the route

A route’s record is built out of two airports’ habits. The hour-by-hour grid for each is on its own page.

MIA to SJU in one number

MIA → SJU

When a flight on this route was late, it was late by about 74 min.

July 2023–June 2026 · 8,271 flights

76.2% of flights arrived on time

Questions about MIA to SJU

Which airline is most reliable from MIA to SJU?
Frontier Airlines — its flights on this pairing arrived on time 76.9% of the time, with 1,469 scheduled. Spirit Airlines came in at 73.2% over 916 scheduled. Airlines with fewer than 100 flights on the route are not rated.
What is the worst month to fly MIA to SJU?
July, at 68.8% of arrivals on time, with 745 flights scheduled. October was the best of the year at 85.2%.
How late are MIA–SJU flights when they are late?
74 min on average, counting only the flights that arrived 15 minutes or more behind schedule. The on-time flights are left out of that average on purpose — mixing them in would flatter it.
How often is the MIA to SJU flight cancelled?
0.8% of scheduled flights on this route were cancelled, July 2023 through June 2026. Diverted flights are counted with the cancellations rather than as late arrivals.
Are these departure or arrival numbers?
Arrival. A flight counts as on time here if it reached the gate at SJU less than 15 minutes behind schedule. Airport pages score departures instead, because that is the number you can act on when you pick a booking time.