Flight OddsDL1721 SJU → BOS
Delta Air Lines · San Juan, PR to Boston, MA · 16 flights observed, 2025-12-20 to 2026-01-04 · 1,674 mi
DL1721 covers more than one route in the data window — the stats below are for SJU → BOS, the one it has flown most recently. The others are linked under “Other routes”.
On-time arrival
60%
Median delay
-5 min
90th percentile
+43 min
Cancellation rate
6%
How often is DL1721 on time?
Across 16 flights on SJU → BOS from 2025-12-20 to 2026-01-04, DL1721 arrived within 15 minutes of schedule 60% of the time. The median arrival delay was -5 min, and the worst 10% of flights arrived +43 min or later. 6% of flights were cancelled.
Delay distribution
Arrival delay for completed flights (excludes cancellations and diversions).
| Arrival | Flights | Share |
|---|---|---|
| Early / on-time | 9 | 60% |
| 16-30 min | 2 | 13% |
| 31-60 min | 3 | 20% |
| 61-120 min | 1 | 7% |
| 2+ hrs | 0 | 0% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2025-12 | 12 | 67% | -1 min |
| 2026-01 | 3 | 33% | +34 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | 2 | 100% |
| Tue | 2 | 100% |
| Wed | 2 | 50% |
| Thu | 2 | 0% |
| Fri | 2 | 0% |
| Sat | 2 | 100% |
| Sun | 3 | 67% |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…