ON TIMEBOARD

DL 4039 on time

Delta Air Lines 4039: Seattle to Bozeman at 7:59 p.m. (past 12 months)

On time
82%
250 flights · likely 77–87%
Cancelled
0.4%
of scheduled flights
Typical arrival
−12 min
median vs schedule
When late
+53 min
average delay
Similar flights
88%
DL, same route & hour

About 1 in 6 DL 4039 flights from Seattle arrived 15+ minutes late, diverted or cancelled over the past year (18%); 0.4% were cancelled. The typical flight landed 12 minutes early.

DL 4039: SEA → BZN

Scheduled to leave Seattle at 7:59 p.m. local time, operated by SkyWest as OO 4039. Over the past year it arrived on time 82% of the time (250 flights), worse than other DL flights on the route at that hour (88%). Last seen in the data Aug 31, 2026.

Usually Delta Air Lines's last flight of the day from Seattle to Bozeman (100% of days). Delta Air Lines's last SEA–BZN flight was cancelled 0.3% of the time, against 0.2% for its earlier ones. If it's cancelled, the next Delta Air Lines flight is usually around 11:45 a.m. the next morning.

Month by month

40%70%100%Jun 2025: too few flights (1 flights)JunJul 2025: too few flights (5 flights)JulDec 2025: too few flights (9 flights)DecJan 2026: 93% on time (30 flights)93JanFeb 2026: 86% on time (28 flights)86FebMar 2026: 84% on time (31 flights)84MarApr 2026: 90% on time (30 flights)90AprMay 2026: 63% on time (30 flights)63MayJun 2026: 90% on time (30 flights)90JunJul 2026: 77% on time (31 flights)77JulAug 2026: 71% on time (31 flights)71Aug

By day of week

DayFlightsOn time
Monday3784%
Tuesday3683%
Wednesday3388%
Thursday3476%
Friday3675%
Saturday3797%
Sunday3773%

Why it was late

Airline (crew, maintenance, ops) 60%Severe weather 23%Air traffic & airport (NAS) 17%

All flights SEA → BZN · Connecting off DL 4039? Check the risk

Questions

How often is DL 4039 from SEA to BZN late?

Delta Air Lines 4039 from Seattle, WA to Bozeman, MT arrived 15 or more minutes late, was diverted or was cancelled on 18% of 250 scheduled flights between September 2025 and August 2026. 0.4% were cancelled.

Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check Delta Air Lines for today's flight. Method.