ON TIMEBOARD

DL 384 on time

Delta Air Lines 384: Boston to Seattle at 7:15 a.m. (past 12 months)

On time
73%
365 flights · likely 68–77%
Cancelled
1.6%
of scheduled flights
Typical arrival
+2 min
median vs schedule
When late
+47 min
average delay
Similar flights
73%
DL, same route & hour

About 1 in 4 DL 384 flights from Boston arrived 15+ minutes late, diverted or cancelled over the past year (27%); 1.6% were cancelled. The typical flight landed 2 minutes late.

DL 384: BOS → SEA

Scheduled to leave Boston at 7:15 a.m. local time. Over the past year it arrived on time 73% of the time (365 flights), in line with other DL flights on the route at that hour (73%). Last seen in the data Aug 31, 2026.

Month by month

30%65%100%Sep 2025: 87% on time (30 flights)87SepOct 2025: 81% on time (31 flights)81OctNov 2025: 80% on time (30 flights)80NovDec 2025: 61% on time (31 flights)61DecJan 2026: 65% on time (31 flights)65JanFeb 2026: 64% on time (28 flights)64FebMar 2026: 35% on time (31 flights)35MarApr 2026: 83% on time (30 flights)83AprMay 2026: 84% on time (31 flights)84MayJun 2026: 70% on time (30 flights)70JunJul 2026: 90% on time (31 flights)90JulAug 2026: 74% on time (31 flights)74Aug

By day of week

DayFlightsOn time
Monday5372%
Tuesday5265%
Wednesday5281%
Thursday5269%
Friday5273%
Saturday5271%
Sunday5279%

Why it was late

Air traffic & airport (NAS) 56%Airline (crew, maintenance, ops) 30%Late inbound plane 13%Severe weather 1%

All flights BOS → SEA · Connecting off DL 384? Check the risk

Questions

How often is DL 384 from BOS to SEA late?

Delta Air Lines 384 from Boston, MA to Seattle, WA arrived 15 or more minutes late, was diverted or was cancelled on 27% of 365 scheduled flights between September 2025 and August 2026. 1.6% 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.