About 1 in 6 UA 1232 flights from Denver arrived 15+ minutes late, diverted or cancelled over the past year (16%); 0.9% were cancelled. The typical flight landed 11 minutes early.
UA 1232: DEN → BOS
Scheduled to leave Denver at 9:40 a.m. local time. Over the past year it arrived on time 84% of the time (236 flights), better than other UA flights on the route at that hour (77%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 34 | 79% |
| Tuesday | 33 | 88% |
| Wednesday | 33 | 82% |
| Thursday | 34 | 85% |
| Friday | 34 | 82% |
| Saturday | 34 | 91% |
| Sunday | 34 | 82% |
Why it was late
All flights DEN → BOS · Connecting off UA 1232? Check the risk
UA 1232: SLC → DEN
Scheduled to leave Salt Lake City at 7:00 a.m. local time. Over the past year it arrived on time 94% of the time (198 flights), in line with other UA flights on the route at that hour (92%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 29 | 97% |
| Tuesday | 27 | 96% |
| Wednesday | 28 | 96% |
| Thursday | 29 | 100% |
| Friday | 29 | 93% |
| Saturday | 29 | 83% |
| Sunday | 27 | 96% |
Why it was late
All flights SLC → DEN · Connecting off UA 1232? Check the risk
Questions
How often is UA 1232 from DEN to BOS late?
United Airlines 1232 from Denver, CO to Boston, MA arrived 15 or more minutes late, was diverted or was cancelled on 16% of 236 scheduled flights between September 2025 and August 2026. 0.9% were cancelled.
How often is UA 1232 from SLC to DEN late?
United Airlines 1232 from Salt Lake City, UT to Denver, CO arrived 15 or more minutes late, was diverted or was cancelled on 6% of 198 scheduled flights between September 2025 and August 2026. 0.5% 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.