ON TIMEBOARD

F9 4989 on time

Frontier Airlines 4989: Denver to San Diego at 10:29 p.m. (past 12 months)

On time
72%
256 flights · likely 66–77%
Cancelled
1.9%
of scheduled flights
Typical arrival
−4 min
median vs schedule
When late
+57 min
average delay
Similar flights
73%
F9, same route & hour

About 1 in 4 F9 4989 flights from Denver arrived 15+ minutes late, diverted or cancelled over the past year (28%); 1.9% were cancelled. The typical flight landed 4 minutes early.

F9 4989: DEN → SAN

Scheduled to leave Denver at 10:29 p.m. local time. Over the past year it arrived on time 72% of the time (256 flights), in line with other F9 flights on the route at that hour (73%). Last seen in the data Aug 31, 2026.

Usually Frontier Airlines's last flight of the day from Denver to San Diego (93% of days). Frontier Airlines's last DEN–SAN flight was cancelled 1.6% of the time, against 1.5% for its earlier ones. If it's cancelled, the next Frontier Airlines flight is usually around 7:40 a.m. the next morning.

Month by month

40%70%100%Sep 2025: too few flights (9 flights)SepOct 2025: too few flights (8 flights)OctNov 2025: too few flights (12 flights)NovDec 2025: 56% on time (25 flights)56DecJan 2026: 67% on time (18 flights)67JanFeb 2026: 84% on time (19 flights)84FebMar 2026: 86% on time (29 flights)86MarApr 2026: 86% on time (22 flights)86AprMay 2026: 73% on time (22 flights)73MayJun 2026: 73% on time (30 flights)73JunJul 2026: 74% on time (31 flights)74JulAug 2026: 45% on time (31 flights)45Aug

By day of week

DayFlightsOn time
Monday4470%
Tuesday2291%
Wednesday2264%
Thursday4665%
Friday4473%
Saturday3281%
Sunday4667%

Why it was late

Late inbound plane 48%Airline (crew, maintenance, ops) 33%Air traffic & airport (NAS) 18%Severe weather 1%

All flights DEN → SAN · Connecting off F9 4989? Check the risk

Questions

How often is F9 4989 from DEN to SAN late?

Frontier Airlines 4989 from Denver, CO to San Diego, CA arrived 15 or more minutes late, was diverted or was cancelled on 28% of 256 scheduled flights between September 2025 and August 2026. 1.9% 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 Frontier Airlines for today's flight. Method.