Best Time to Fly MIA to SJU: On-Time Stats by Hour & Airline
Miami International → Luis Munoz Marin International
Data through July 2026 · Last updated October 18, 2026
2,638 flights were scheduled from Miami (MIA) to San Juan (SJU) in the last 12 months, and 75.5% of those that flew arrived on time, 2.1 points below the US average of 77.6%.
American Airlines was the most punctual of the 3 airlines on the route at 77.3%, while Spirit Airlines trailed at 58.7%.
May has been the best month (84% on time) and Sunday the weakest day of the week (70%).
0.9% of flights were cancelled, versus 1.8% nationally.
MIA to SJU on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| American Airlines | 77.3% | 69 min | 0.5% | 2,109 |
| Frontier Airlines | 71.6% | 84 min | 1.6% | 379 |
| Spirit Airlines | 58.7% | 108 min | 4.7% | 150 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly MIA to SJU
On-time arrival % by scheduled departure hour (local time), 5,403 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 12am–1am | Limited data | 12 | |
| 5am–6am | 79.3% | 3.3% | 60 |
| 6am–7am | 88.1% | 1.1% | 281 |
| 7am–8am | 93.0% | 0.6% | 346 |
| 8am–9am | 90.0% | 0.3% | 742 |
| 9am–10am | 84.4% | 0.7% | 279 |
| 10am–11am | 81.1% | 0.2% | 445 |
| 11am–12pm | 79.2% | 0.7% | 155 |
| 12pm–1pm | 69.6% | 0.3% | 597 |
| 1pm–2pm | 72.9% | 0.5% | 419 |
| 2pm–3pm | 66.4% | 0.8% | 379 |
| 3pm–4pm | 70.2% | 0.8% | 395 |
| 4pm–5pm | 70.9% | 1.8% | 56 |
| 5pm–6pm | 65.9% | 0.9% | 213 |
| 6pm–7pm | 70.2% | 0.9% | 325 |
| 7pm–8pm | 67.0% | 1.0% | 199 |
| 8pm–9pm | 68.6% | 1.1% | 177 |
| 9pm–10pm | 63.1% | 3.5% | 230 |
| 10pm–11pm | 59.1% | 1.4% | 72 |
| 11pm–12am | Limited data | 21 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on MIA to SJU
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 76.7% | -1.0 pts | 0.0% | 116 |
| Christmas & New Year (Dec 20 - Jan 3) | 75.3% | -2.5 pts | 4.3% | 279 |
| Summer peak (Jun 15 - Aug 15) | 70.3% | -7.4 pts | 0.8% | 900 |
| All other days | 77.8% | — | 0.6% | 4,108 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).