ON TIMEBOARD

UA 4256 on time

United Airlines 4256: Houston to Birmingham at 4:20 p.m. (past 12 months)

On time
79%
150 flights · likely 72–85%
Cancelled
1.3%
of scheduled flights
Typical arrival
−7 min
median vs schedule
When late
+61 min
average delay
Similar flights
79%
UA, same route & hour

About 1 in 5 UA 4256 flights from Houston arrived 15+ minutes late, diverted or cancelled over the past year (21%); 1.3% were cancelled. The typical flight landed 7 minutes early.

UA 4256: IAH → BHM

Scheduled to leave Houston at 4:20 p.m. local time, operated by CommutAir as C5 4256. Over the past year it arrived on time 79% of the time (150 flights), in line with other UA flights on the route at that hour (79%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Jul 2025: 54% on time (26 flights)54JulAug 2025: 85% on time (27 flights)85AugSep 2025: 81% on time (21 flights)81SepDec 2025: too few flights (14 flights)DecJan 2026: too few flights (6 flights)JanFeb 2026: 87% on time (15 flights)87FebMar 2026: 81% on time (27 flights)81MarApr 2026: too few flights (7 flights)AprMay 2026: too few flights (6 flights)MayJun 2026: 71% on time (17 flights)71JunJul 2026: 75% on time (16 flights)75JulAug 2026: 81% on time (21 flights)81Aug

By day of week

DayFlightsOn time
Monday2969%
Tuesday8—
Wednesday18—
Thursday2886%
Friday2871%
Saturday11—
Sunday2886%

Why it was late

Airline (crew, maintenance, ops) 55%Late inbound plane 31%Air traffic & airport (NAS) 12%Severe weather 1%

All flights IAH → BHM · Connecting off UA 4256? Check the risk

Questions

How often is UA 4256 from IAH to BHM late?

United Airlines 4256 from Houston, TX to Birmingham, AL arrived 15 or more minutes late, was diverted or was cancelled on 21% of 150 scheduled flights between September 2025 and August 2026. 1.3% 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.