Ontario, CA → Seattle, WA flight delays
ONT → SEA · all airlines · 200 flights · April 2026 · source: US BTS
This route is delayed
9%of the time, by +50 min on average when it does.
This is history, not a promise — your specific flight could well be on time.
On-time rate
91%
Delayed 3h+
0.5%
Cancelled
0.5%
Avg when late
+50m
Best & worst day to fly
Most on-time
Saturday
delayed 4%
Worst
Sunday
delayed 15%
Which airline is most punctual on ONT → SEA?
SkyWestdelayed 6%
Alaskadelayed 12%
Frequently asked
How often is the Ontario, CA to Seattle, WA flight delayed?
About 9% of ONT → SEA flights arrive late (15+ minutes), by an average of 50 minutes when they do, based on 200 flights in April 2026.
Which airline is most punctual on ONT → SEA?
SkyWest, delayed 6% of the time — the best of the 2 airlines flying this route.
What is the best day to fly ONT → SEA?
Saturday is the most on-time (delayed 4%), while Sunday is the worst (delayed 15%).
Airport overviews