ON TIMEBOARD

AS 538 on time

Alaska Airlines 538: Seattle to Chicago at 5:48 p.m. (past 12 months)

On time
81%
350 flights · likely 76–85%
Cancelled
0.6%
of scheduled flights
Typical arrival
−10 min
median vs schedule
When late
+64 min
average delay
Similar flights
80%
AS, same route & hour

About 1 in 5 AS 538 flights from Seattle arrived 15+ minutes late, diverted or cancelled over the past year (19%); 0.6% were cancelled. The typical flight landed 10 minutes early.

AS 538: SEA → ORD

Scheduled to leave Seattle at 5:48 p.m. local time. Over the past year it arrived on time 81% of the time (350 flights), in line with other AS flights on the route at that hour (80%). Last seen in the data Aug 31, 2026.

Usually Alaska Airlines's last flight of the day from Seattle to Chicago (97% of days). Alaska Airlines's last SEA–ORD flight was cancelled 0.5% of the time, against 1.3% for its earlier ones. If it's cancelled, the next Alaska Airlines flight is usually around 12:17 a.m. the next morning.

Month by month

40%70%100%Sep 2025: 77% on time (30 flights)77SepOct 2025: 89% on time (28 flights)89OctNov 2025: 75% on time (28 flights)75NovDec 2025: 77% on time (22 flights)77DecJan 2026: 77% on time (31 flights)77JanFeb 2026: 100% on time (28 flights)100FebMar 2026: 77% on time (31 flights)77MarApr 2026: 80% on time (30 flights)80AprMay 2026: 97% on time (31 flights)97MayJun 2026: 77% on time (30 flights)77JunJul 2026: 70% on time (30 flights)70JulAug 2026: 74% on time (31 flights)74Aug

By day of week

DayFlightsOn time
Monday5379%
Tuesday4990%
Wednesday4984%
Thursday4973%
Friday5178%
Saturday4885%
Sunday5176%

Why it was late

Air traffic & airport (NAS) 53%Airline (crew, maintenance, ops) 27%Late inbound plane 16%Severe weather 4%

All flights SEA → ORD · Connecting off AS 538? Check the risk

Questions

How often is AS 538 from SEA to ORD late?

Alaska Airlines 538 from Seattle, WA to Chicago, IL arrived 15 or more minutes late, was diverted or was cancelled on 19% of 350 scheduled flights between September 2025 and August 2026. 0.6% 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 Alaska Airlines for today's flight. Method.