About 1 in 2 UA 1791 flights from Los Angeles arrived 15+ minutes late, diverted or cancelled over the past year (45%); 0.0% were cancelled. The typical flight landed 11 minutes late.
UA 1791: LAX → SFO
Scheduled to leave Los Angeles at 10:26 a.m. local time. Over the past year it arrived on time 55% of the time (316 flights), in line with other UA flights on the route at that hour (55%). Last seen in the data Aug 10, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 50 | 54% |
| Tuesday | 45 | 58% |
| Wednesday | 44 | 55% |
| Thursday | 48 | 54% |
| Friday | 49 | 55% |
| Saturday | 33 | 52% |
| Sunday | 47 | 60% |
Why it was late
All flights LAX → SFO · Connecting off UA 1791? Check the risk
UA 1791: SFO → IAD
Scheduled to leave San Francisco at 1:15 p.m. local time. Over the past year it arrived on time 69% of the time (121 flights), worse than other UA flights on the route at that hour (76%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 18 | — |
| Tuesday | 14 | — |
| Wednesday | 17 | — |
| Thursday | 18 | — |
| Friday | 18 | — |
| Saturday | 18 | — |
| Sunday | 18 | — |
Why it was late
All flights SFO → IAD · Connecting off UA 1791? Check the risk
Questions
How often is UA 1791 from LAX to SFO late?
United Airlines 1791 from Los Angeles, CA to San Francisco, CA arrived 15 or more minutes late, was diverted or was cancelled on 45% of 316 scheduled flights between September 2025 and August 2026. 0.0% were cancelled.
How often is UA 1791 from SFO to IAD late?
United Airlines 1791 from San Francisco, CA to Washington, DC arrived 15 or more minutes late, was diverted or was cancelled on 31% of 121 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 United Airlines for today's flight. Method.