About 1 in 7 UA 2129 flights from San Diego arrived 15+ minutes late, diverted or cancelled over the past year (14%); 1.2% were cancelled. The typical flight landed 12 minutes early.
UA 2129: SAN → IAD
Scheduled to leave San Diego at 9:45 p.m. local time. Over the past year it arrived on time 86% of the time (326 flights), in line with other UA flights on the route at that hour (84%). Last seen in the data Aug 31, 2026.
Usually United Airlines's last flight of the day from San Diego to Washington (100% of days). United Airlines's last SAN–IAD flight was cancelled 1.1% of the time, against 0.6% for its earlier ones. If it's cancelled, the next United Airlines flight is usually around 8:00 a.m. the next morning.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 45 | 82% |
| Tuesday | 44 | 93% |
| Wednesday | 52 | 87% |
| Thursday | 52 | 85% |
| Friday | 52 | 88% |
| Saturday | 29 | 90% |
| Sunday | 52 | 81% |
Why it was late
All flights SAN → IAD · Connecting off UA 2129? Check the risk
Questions
How often is UA 2129 from SAN to IAD late?
United Airlines 2129 from San Diego, CA to Washington, DC arrived 15 or more minutes late, was diverted or was cancelled on 14% of 326 scheduled flights between September 2025 and August 2026. 1.2% 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.