Seattle, WA → Boston, MA flight delays
SEA → BOS · all airlines · 254 flights · May 2026 · source: US BTS
This route is delayed
17%of the time, by +39 min on average when it does.
This is history, not a promise — your specific flight could well be on time.
On-time rate
83%
Delayed 3h+
0%
Cancelled
0.4%
Avg when late
+39m
Best & worst day to fly
Most on-time
Tuesday
delayed 9%
Worst
Saturday
delayed 22%
Which airline is most punctual on SEA → BOS?
Deltadelayed 6%
Alaskadelayed 19%
Frequently asked
How often is the Seattle, WA to Boston, MA flight delayed?
About 17% of SEA → BOS flights arrive late (15+ minutes), by an average of 39 minutes when they do, based on 254 flights in May 2026.
Which airline is most punctual on SEA → BOS?
Delta, delayed 6% of the time — the best of the 2 airlines flying this route.
What is the best day to fly SEA → BOS?
Tuesday is the most on-time (delayed 9%), while Saturday is the worst (delayed 22%).
Airport overviews