Flight OddsDL3991 SFO → SEA
Delta Air Lines · San Francisco, CA to Seattle, WA · 292 flights observed, 2025-07-01 to 2026-06-30 · 679 mi
DL3991 covers more than one route in the data window — the stats below are for SFO → SEA, the one it has flown most recently. The others are linked under “Other routes”.
On-time arrival
71%
Median delay
-4 min
90th percentile
+46 min
Cancellation rate
1%
How often is DL3991 on time?
Across 292 flights on SFO → SEA from 2025-07-01 to 2026-06-30, DL3991 arrived within 15 minutes of schedule 71% of the time. The median arrival delay was -4 min, and the worst 10% of flights arrived +46 min or later. 1% of flights were cancelled.
Delay distribution
Arrival delay for completed flights (excludes cancellations and diversions).
| Arrival | Flights | Share |
|---|---|---|
| Early / on-time | 207 | 71% |
| 16-30 min | 32 | 11% |
| 31-60 min | 36 | 12% |
| 61-120 min | 10 | 3% |
| 2+ hrs | 5 | 2% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2025-07 | 29 | 93% | -9 min |
| 2025-08 | 29 | 90% | -10 min |
| 2025-09 | 23 | 78% | -10 min |
| 2025-10 | 27 | 56% | +15 min |
| 2025-11 | 25 | 68% | +10 min |
| 2025-12 | 19 | 63% | +1 min |
| 2026-01 | 13 | 92% | -14 min |
| 2026-02 | 11 | 91% | -2 min |
| 2026-03 | 23 | 65% | +7 min |
| 2026-04 | 30 | 63% | +18 min |
| 2026-05 | 31 | 71% | +13 min |
| 2026-06 | 30 | 47% | +29 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | 44 | 66% |
| Tue | 44 | 82% |
| Wed | 43 | 70% |
| Thu | 42 | 57% |
| Fri | 39 | 64% |
| Sat | 35 | 91% |
| Sun | 43 | 72% |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…