ON TIMEBOARD

AS 737 on time

Alaska Airlines 737: Seattle to Washington at 9:13 a.m.; Washington to Seattle at 6:14 p.m. (past 12 months). Figures below the title are for SEA → IAD, its busiest leg

On time
81%
237 flights · likely 76–86%
Cancelled
0.4%
of scheduled flights
Typical arrival
−7 min
median vs schedule
When late
+42 min
average delay
Similar flights
82%
AS, same route & hour

About 1 in 5 AS 737 flights from Seattle arrived 15+ minutes late, diverted or cancelled over the past year (19%); 0.4% were cancelled. The typical flight landed 7 minutes early.

AS 737: SEA → IAD

Scheduled to leave Seattle at 9:13 a.m. local time. Over the past year it arrived on time 81% of the time (237 flights), in line with other AS flights on the route at that hour (82%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Jan 2026: 72% on time (25 flights)72JanFeb 2026: 89% on time (28 flights)89FebMar 2026: 84% on time (31 flights)84MarApr 2026: 83% on time (30 flights)83AprMay 2026: 81% on time (31 flights)81MayJun 2026: 80% on time (30 flights)80JunJul 2026: 84% on time (31 flights)84JulAug 2026: 77% on time (31 flights)77Aug

By day of week

DayFlightsOn time
Monday3479%
Tuesday3382%
Wednesday3482%
Thursday3479%
Friday3482%
Saturday3479%
Sunday3485%

Why it was late

Airline (crew, maintenance, ops) 41%Air traffic & airport (NAS) 31%Late inbound plane 18%Severe weather 11%

All flights SEA → IAD · Connecting off AS 737? Check the risk

AS 737: IAD → SEA

Scheduled to leave Washington at 6:14 p.m. local time. Over the past year it arrived on time 57% of the time (160 flights), worse than other AS flights on the route at that hour (63%). Last seen in the data Aug 31, 2026.

Usually Alaska Airlines's last flight of the day from Washington to Seattle (100% of days). Alaska Airlines's last IAD–SEA flight was cancelled 2.0% of the time, against 0.6% for its earlier ones. If it's cancelled, the next Alaska Airlines flight is usually around 6:03 a.m. the next morning.

Month by month

40%70%100%Mar 2026: too few flights (14 flights)MarApr 2026: 64% on time (28 flights)64AprMay 2026: 63% on time (27 flights)63MayJun 2026: 50% on time (30 flights)50JunJul 2026: 67% on time (30 flights)67JulAug 2026: 65% on time (31 flights)65Aug

By day of week

DayFlightsOn time
Monday2458%
Tuesday2045%
Wednesday2458%
Thursday2454%
Friday2463%
Saturday2065%
Sunday2458%

Why it was late

Late inbound plane 31%Air traffic & airport (NAS) 29%Severe weather 23%Airline (crew, maintenance, ops) 16%Security 1%

All flights IAD → SEA · Connecting off AS 737? Check the risk

Questions

How often is AS 737 from SEA to IAD late?

Alaska Airlines 737 from Seattle, WA to Washington, DC arrived 15 or more minutes late, was diverted or was cancelled on 19% of 237 scheduled flights between September 2025 and August 2026. 0.4% were cancelled.

How often is AS 737 from IAD to SEA late?

Alaska Airlines 737 from Washington, DC to Seattle, WA arrived 15 or more minutes late, was diverted or was cancelled on 43% of 160 scheduled flights between September 2025 and August 2026. 1.3% 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 Alaska Airlines for today's flight. Method.