Flight history · Aug 2025 – Jul 2026 · US DOT on-time records
DL 3959 · Seattle (SEA) → Boise (BOI)
Sold by Delta, flown by SkyWest. Still flying: 56 of the last 56 days (Daily).
Arrives on time88%within 15 minutes, of 172 flights
Cancelled0.0%of scheduled flights
An hour or more late6%of flights that operated
When late, on average76 minlate, among flights 15+ min late
Schedule
Typical times in the Jun 6 – Jul 31, 2026 schedule, local at each airport (Boise is 1 h ahead of Seattle).
- Leaves SEA
- 12:30
- Arrives BOI
- 15:12
- Flight time
- 1h 42m
- Days flown, last 8 weeks
- 56 of 56
Each square is a day, Sat Jun 6 to Fri Jul 31, two weeks per row (each column is the same weekday); filled = flew.
How late it arrives
Share of flights that operated arriving more than this late.
Horizontal: minutes late at arrival (0 to 3 hours). Vertical: share of flights later than that.
Its hour at SEA
All flights leaving Seattle (SEA) at 12–1 pm, wherever they’re going: 79% left within 15 minutes and 0.8% were cancelled (8,431 flights in the year). Other Delta flights on this route →
Upcoming forecasts
Our odds that this flight is late or cancelled on the days we publish.