ON TIMEBOARD

UA 737 on time

United Airlines 737: Seattle to San Francisco at 7:37 p.m. (past 12 months)

On time
54%
362 flights · likely 48–59%
Cancelled
0.5%
of scheduled flights
Typical arrival
+9 min
median vs schedule
When late
+63 min
average delay
Similar flights
49%
UA, same route & hour

About 1 in 2 UA 737 flights from Seattle arrived 15+ minutes late, diverted or cancelled over the past year (46%); 0.5% were cancelled. The typical flight landed 9 minutes late.

UA 737: SEA → SFO

Scheduled to leave Seattle at 7:37 p.m. local time. Over the past year it arrived on time 54% of the time (362 flights), better than other UA flights on the route at that hour (49%). Last seen in the data Aug 31, 2026.

Usually United Airlines's last flight of the day from Seattle to San Francisco (52% of days). United Airlines's last SEA–SFO flight was cancelled 0.5% of the time, against 0.9% for its earlier ones. If it's cancelled, the next United Airlines flight is usually around 5:15 a.m. the next morning.

Month by month

10%55%100%Sep 2025: 60% on time (30 flights)60SepOct 2025: 68% on time (31 flights)68OctNov 2025: 81% on time (27 flights)81NovDec 2025: 61% on time (31 flights)61DecJan 2026: 77% on time (31 flights)77JanFeb 2026: 68% on time (28 flights)68FebMar 2026: 90% on time (31 flights)90MarApr 2026: 20% on time (30 flights)20AprMay 2026: 26% on time (31 flights)26MayJun 2026: 17% on time (30 flights)17JunJul 2026: 26% on time (31 flights)26JulAug 2026: 52% on time (31 flights)52Aug

By day of week

DayFlightsOn time
Monday5338%
Tuesday5269%
Wednesday5246%
Thursday5151%
Friday5246%
Saturday5066%
Sunday5260%

Why it was late

Air traffic & airport (NAS) 62%Late inbound plane 30%Airline (crew, maintenance, ops) 5%Severe weather 3%

All flights SEA → SFO · Connecting off UA 737? Check the risk

Questions

How often is UA 737 from SEA to SFO late?

United Airlines 737 from Seattle, WA to San Francisco, CA arrived 15 or more minutes late, was diverted or was cancelled on 46% of 362 scheduled flights between September 2025 and August 2026. 0.5% 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 United Airlines for today's flight. Method.