UA543
UA543 (United Airlines) is a multi-stop service on 21 routes, busiest Chicago to San Francisco. Of 895 departures recorded from October 2024 to July 2026, 74.9% left on time, according to the US BTS.
- On-time departures74.9%of 895 flights
- Average delay18.0 min
- July 202660▲ 100.0%vs July 2025
- Cancelled1.7%
- Legs flown under this number21
Recorded departures by month
All legs under this number combined; see the leg table.
The most recent periods19 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 37 | 31 | ▼ 16.2% |
| February | 28 | 28 | 0.0% |
| March | 57 | 58 | ▲ 1.8% |
| April | 30 | 60 | ▲ 100.0% |
| May | 30 | 73 | ▲ 143.3% |
| June | 30 | 89 | ▲ 196.7% |
| July | 30 | 60 | ▲ 100.0% |
| August | 31 | – | – |
| September | 27 | – | – |
| October | 31 | – | in progress |
| November | 31 | – | – |
| December | 25 | – | – |
| Year to date (Jan–Jul) | 242 | 399 | ▲ 64.9% |
according to the US BTS · October 2024 → July 2026
On-time departures by month
On time = departure within 15 minutes of schedule. Non-cancelled flights with a recorded delay only.
The most recent periods19 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 51.4% | 86.7% | ▲ 68.5% |
| February | 50.0% | 88.9% | ▲ 77.8% |
| March | 75.4% | 87.7% | ▲ 16.3% |
| April | 83.3% | 74.1% | ▼ 11.0% |
| May | 93.3% | 69.4% | ▼ 25.6% |
| June | 96.6% | 61.4% | ▼ 36.4% |
| July | 96.4% | 44.8% | ▼ 53.5% |
| August | 93.6% | – | – |
| September | 88.9% | – | – |
| October | 96.8% | – | in progress |
| November | 63.3% | – | – |
| December | 64.0% | – | – |
| Year-to-date average (Jan–Jul) | 78.1% | 73.3% | ▼ 6.1% |
according to the US BTS · October 2024 → July 2026
Average departure delay by month
according to the US BTS · October 2024 → July 2026
Cancelled departures by month
The most recent periods19 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 2 | 1 | ▼ 50.0% |
| February | 0 | 1 | – |
| March | 0 | 1 | – |
| April | 0 | 2 | – |
| May | 0 | 1 | – |
| June | 1 | 1 | 0.0% |
| July | 2 | 2 | 0.0% |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 1 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 5 | 9 | ▲ 80.0% |
according to the US BTS · October 2024 → July 2026
This is a historical record of departures already flown, not a forecast for your flight.
Several legs: the headline figure averages all of them. See the leg table.
Cancellation share
- Not cancelled 98.3% 880
- Cancelled 1.7% 15
Share of all recorded flights in the period, all legs. · Oct 12, 2024 → Jul 31, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
10Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 20 | 20 | 100.0% | 0 |
| November 2024 | 29 | 29 | 79.3% | 0 |
| December 2024 | 60 | 60 | 70.0% | 0 |
| January 2025 | 37 | 35 | 51.4% | 2 |
| February 2025 | 28 | 28 | 50.0% | 0 |
| March 2025 | 57 | 57 | 75.4% | 0 |
| April 2025 | 30 | 30 | 83.3% | 0 |
| May 2025 | 30 | 30 | 93.3% | 0 |
| June 2025 | 30 | 29 | 96.6% | 1 |
| July 2025 | 30 | 28 | 96.4% | 2 |
| August 2025 | 31 | 31 | 93.6% | 0 |
| September 2025 | 27 | 27 | 88.9% | 0 |
| October 2025 | 31 | 31 | 96.8% | 0 |
| November 2025 | 31 | 30 | 63.3% | 1 |
| December 2025 | 25 | 25 | 64.0% | 0 |
| January 2026 | 31 | 30 | 86.7% | 1 |
| February 2026 | 28 | 27 | 88.9% | 1 |
| March 2026 | 58 | 57 | 87.7% | 1 |
| April 2026 | 60 | 58 | 74.1% | 2 |
| May 2026 | 73 | 72 | 69.4% | 1 |
| June 2026 | 89 | 88 | 61.4% | 1 |
| July 2026 | 60 | 58 | 44.8% | 2 |