About 1 in 6 F9 3665 flights from Denver arrived 15+ minutes late, diverted or cancelled over the past year (18%); 0.0% were cancelled. The typical flight landed 10 minutes early.
F9 3665: DEN → SMF
Scheduled to leave Denver at 9:01 a.m. local time. Over the past year it arrived on time 82% of the time (194 flights), in line with other F9 flights on the route at that hour (82%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 51 | 80% |
| Tuesday | 2 | — |
| Wednesday | 18 | — |
| Thursday | 23 | 91% |
| Friday | 50 | 72% |
| Saturday | 20 | 90% |
| Sunday | 30 | 80% |
Why it was late
All flights DEN → SMF · Connecting off F9 3665? Check the risk
Questions
How often is F9 3665 from DEN to SMF late?
Frontier Airlines 3665 from Denver, CO to Sacramento, CA arrived 15 or more minutes late, was diverted or was cancelled on 18% of 194 scheduled flights between September 2025 and August 2026. 0.0% 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.