About 1 in 7 AS 603 flights from Phoenix arrived 15+ minutes late, diverted or cancelled over the past year (14%); 1.1% were cancelled. The typical flight landed 11 minutes early.
AS 603: PHX → SEA
Scheduled to leave Phoenix at 11:23 a.m. local time. Over the past year it arrived on time 86% of the time (347 flights), in line with other AS flights on the route at that hour (87%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 53 | 81% |
| Tuesday | 52 | 87% |
| Wednesday | 52 | 96% |
| Thursday | 51 | 84% |
| Friday | 50 | 82% |
| Saturday | 42 | 88% |
| Sunday | 47 | 85% |
Why it was late
All flights PHX → SEA · Connecting off AS 603? Check the risk
Questions
How often is AS 603 from PHX to SEA late?
Alaska Airlines 603 from Phoenix, AZ to Seattle, WA arrived 15 or more minutes late, was diverted or was cancelled on 14% of 347 scheduled flights between September 2025 and August 2026. 1.1% 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.