ON TIMEBOARD

UA 4323 on time

United Airlines 4323: Houston to Mobile at 4:40 p.m. (past 12 months)

On time
83%
336 flights · likely 79–87%
Cancelled
0.9%
of scheduled flights
Typical arrival
−12 min
median vs schedule
When late
+95 min
average delay
Similar flights
83%
UA, same route & hour

About 1 in 6 UA 4323 flights from Houston arrived 15+ minutes late, diverted or cancelled over the past year (17%); 0.9% were cancelled. The typical flight landed 12 minutes early.

UA 4323: IAH → MOB

Scheduled to leave Houston at 4:40 p.m. local time, operated by CommutAir as C5 4323. Over the past year it arrived on time 83% of the time (336 flights), in line with other UA flights on the route at that hour (83%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Sep 2025: 96% on time (27 flights)96SepOct 2025: 94% on time (31 flights)94OctNov 2025: 80% on time (30 flights)80NovDec 2025: 75% on time (16 flights)75DecJan 2026: 88% on time (26 flights)88JanFeb 2026: 86% on time (28 flights)86FebMar 2026: 77% on time (30 flights)77MarApr 2026: 88% on time (26 flights)88AprMay 2026: 74% on time (31 flights)74MayJun 2026: 67% on time (30 flights)67JunJul 2026: 80% on time (30 flights)80JulAug 2026: 90% on time (31 flights)90Aug

By day of week

DayFlightsOn time
Monday5078%
Tuesday5088%
Wednesday4990%
Thursday4980%
Friday4984%
Saturday4085%
Sunday4978%

Why it was late

Late inbound plane 47%Airline (crew, maintenance, ops) 40%Air traffic & airport (NAS) 9%Severe weather 4%

All flights IAH → MOB · Connecting off UA 4323? Check the risk

Questions

How often is UA 4323 from IAH to MOB late?

United Airlines 4323 from Houston, TX to Mobile, AL arrived 15 or more minutes late, was diverted or was cancelled on 17% of 336 scheduled flights between September 2025 and August 2026. 0.9% 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.