ON TIMEBOARD

DL 3918 on time

Delta Air Lines 3918: Portland to Seattle at 5:50 p.m.; Seattle to Portland at 3:55 p.m. (past 12 months). Figures below the title are for PDX → SEA, its busiest leg

On time
84%
324 flights · likely 80–88%
Cancelled
0.3%
of scheduled flights
Typical arrival
−10 min
median vs schedule
When late
+44 min
average delay
Similar flights
83%
DL, same route & hour

About 1 in 6 DL 3918 flights from Portland arrived 15+ minutes late, diverted or cancelled over the past year (16%); 0.3% were cancelled. The typical flight landed 10 minutes early.

DL 3918: PDX → SEA

Scheduled to leave Portland at 5:50 p.m. local time, operated by SkyWest as OO 3918. Over the past year it arrived on time 84% of the time (324 flights), in line with other DL flights on the route at that hour (83%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Sep 2025: 90% on time (30 flights)90SepOct 2025: 90% on time (31 flights)90OctNov 2025: 97% on time (29 flights)97NovDec 2025: 95% on time (19 flights)95DecJan 2026: 85% on time (27 flights)85JanFeb 2026: 96% on time (28 flights)96FebMar 2026: 71% on time (31 flights)71MarApr 2026: too few flights (12 flights)AprMay 2026: 60% on time (25 flights)60MayJun 2026: 83% on time (30 flights)83JunJul 2026: 87% on time (31 flights)87JulAug 2026: 68% on time (31 flights)68Aug

By day of week

DayFlightsOn time
Monday4789%
Tuesday4685%
Wednesday4685%
Thursday4670%
Friday4779%
Saturday4698%
Sunday4683%

Why it was late

Airline (crew, maintenance, ops) 38%Severe weather 37%Air traffic & airport (NAS) 24%Security 1%

All flights PDX → SEA · Connecting off DL 3918? Check the risk

DL 3918: SEA → PDX

Scheduled to leave Seattle at 3:55 p.m. local time, operated by SkyWest as OO 3918. Over the past year it arrived on time 83% of the time (323 flights), in line with other DL flights on the route at that hour (80%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Sep 2025: 83% on time (30 flights)83SepOct 2025: 81% on time (31 flights)81OctNov 2025: 93% on time (28 flights)93NovDec 2025: 95% on time (19 flights)95DecJan 2026: 85% on time (27 flights)85JanFeb 2026: 93% on time (28 flights)93FebMar 2026: 77% on time (31 flights)77MarApr 2026: too few flights (12 flights)AprMay 2026: 60% on time (25 flights)60MayJun 2026: 87% on time (30 flights)87JunJul 2026: 90% on time (31 flights)90JulAug 2026: 71% on time (31 flights)71Aug

By day of week

DayFlightsOn time
Monday4789%
Tuesday4687%
Wednesday4680%
Thursday4777%
Friday4777%
Saturday4493%
Sunday4680%

Why it was late

Airline (crew, maintenance, ops) 59%Severe weather 31%Air traffic & airport (NAS) 10%

All flights SEA → PDX · Connecting off DL 3918? Check the risk

Questions

How often is DL 3918 from PDX to SEA late?

Delta Air Lines 3918 from Portland, OR to Seattle, WA arrived 15 or more minutes late, was diverted or was cancelled on 16% of 324 scheduled flights between September 2025 and August 2026. 0.3% were cancelled.

How often is DL 3918 from SEA to PDX late?

Delta Air Lines 3918 from Seattle, WA to Portland, OR arrived 15 or more minutes late, was diverted or was cancelled on 17% of 323 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.