ON TIMEBOARD

DL 3953 on time

Delta Air Lines 3953: Portland to Seattle at 9:20 a.m.; Seattle to Portland at 7:25 a.m. (past 12 months). Figures below the title are for PDX → SEA, its busiest leg

On time
82%
365 flights · likely 78–86%
Cancelled
0.5%
of scheduled flights
Typical arrival
−8 min
median vs schedule
When late
+45 min
average delay
Similar flights
82%
DL, same route & hour

About 1 in 6 DL 3953 flights from Portland arrived 15+ minutes late, diverted or cancelled over the past year (18%); 0.5% were cancelled. The typical flight landed 8 minutes early.

DL 3953: PDX → SEA

Scheduled to leave Portland at 9:20 a.m. local time, operated by SkyWest as OO 3953. Over the past year it arrived on time 82% of the time (365 flights), in line with other DL flights on the route at that hour (82%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Sep 2025: 87% on time (30 flights)87SepOct 2025: 81% on time (31 flights)81OctNov 2025: 83% on time (30 flights)83NovDec 2025: 74% on time (31 flights)74DecJan 2026: 87% on time (31 flights)87JanFeb 2026: 93% on time (28 flights)93FebMar 2026: 81% on time (31 flights)81MarApr 2026: 80% on time (30 flights)80AprMay 2026: 84% on time (31 flights)84MayJun 2026: 70% on time (30 flights)70JunJul 2026: 94% on time (31 flights)94JulAug 2026: 74% on time (31 flights)74Aug

By day of week

DayFlightsOn time
Monday5383%
Tuesday5287%
Wednesday5285%
Thursday5277%
Friday5281%
Saturday5281%
Sunday5283%

Why it was late

Airline (crew, maintenance, ops) 64%Air traffic & airport (NAS) 21%Severe weather 15%

All flights PDX → SEA · Connecting off DL 3953? Check the risk

DL 3953: SEA → PDX

Scheduled to leave Seattle at 7:25 a.m. local time, operated by SkyWest as OO 3953. Over the past year it arrived on time 93% of the time (365 flights), in line with other DL flights on the route at that hour (93%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Sep 2025: 100% on time (30 flights)100SepOct 2025: 100% on time (31 flights)100OctNov 2025: 93% on time (30 flights)93NovDec 2025: 84% on time (31 flights)84DecJan 2026: 87% on time (31 flights)87JanFeb 2026: 96% on time (28 flights)96FebMar 2026: 90% on time (31 flights)90MarApr 2026: 97% on time (30 flights)97AprMay 2026: 97% on time (31 flights)97MayJun 2026: 83% on time (30 flights)83JunJul 2026: 97% on time (31 flights)97JulAug 2026: 90% on time (31 flights)90Aug

By day of week

DayFlightsOn time
Monday5389%
Tuesday5296%
Wednesday5292%
Thursday5296%
Friday5298%
Saturday5292%
Sunday5287%

Why it was late

Airline (crew, maintenance, ops) 78%Severe weather 17%Air traffic & airport (NAS) 5%

All flights SEA → PDX · Connecting off DL 3953? Check the risk

Questions

How often is DL 3953 from PDX to SEA late?

Delta Air Lines 3953 from Portland, OR to Seattle, WA arrived 15 or more minutes late, was diverted or was cancelled on 18% of 365 scheduled flights between September 2025 and August 2026. 0.5% were cancelled.

How often is DL 3953 from SEA to PDX late?

Delta Air Lines 3953 from Seattle, WA to Portland, OR arrived 15 or more minutes late, was diverted or was cancelled on 7% of 365 scheduled flights between September 2025 and August 2026. 0.3% 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.