DL1399
Delta Air Lines flight 1399 — Boston (BOS) to Miami (MIA)
On time
81%
Avg delay
~92 min
Cancelled
1.1%
DL1399 is a reliable flight. About 81% of departures arrive on time. When delays happen, the most common cause is airline operations.
Monthly breakdown
| Month | On time | Cancelled | Avg delay |
|---|---|---|---|
| 2026-07 | 90% | 6.5% | 182 min |
| 2026-07 | 77% | 0.0% | 130 min |
| 2026-06 | 83% | 0.0% | 64 min |
| 2026-06 | 83% | 0.0% | 72 min |
| 2026-05 | 84% | 0.0% | 221 min |
| 2026-05 | 76% | 0.0% | 66 min |
| 2026-04 | 83% | 0.0% | 47 min |
| 2026-03 | 87% | 0.0% | 109 min |
| 2026-02 | 78% | 8.0% | 53 min |
| 2026-01 | 80% | 7.4% | 127 min |
| 2025-12 | 74% | 0.0% | 49 min |
| 2025-12 | 74% | 0.0% | 49 min |
Top delay cause
airline operations
Based on 2,076 tracked departures
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Get a free briefingData last updated October 2026. Source: Bureau of Transportation Statistics.