UA1599
UA1599 (United Airlines) is a multi-stop service on 13 routes, busiest Chicago to Denver. Of 720 departures recorded from October 2024 to July 2026, 85.2% left on time, according to the US BTS.
- On-time departures85.2%of 720 flights
- Average delay12.8 min
- July 202631▲ 0.0%vs July 2025
- Cancelled0.4%
- Legs flown under this number13
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 | 33 | 31 | ▼ 6.1% |
| February | 28 | 45 | ▲ 60.7% |
| March | 31 | 59 | ▲ 90.3% |
| April | 30 | 30 | 0.0% |
| May | 31 | 31 | 0.0% |
| June | 30 | 30 | 0.0% |
| July | 31 | 31 | 0.0% |
| August | 31 | – | – |
| September | 30 | – | – |
| October | 31 | – | in progress |
| November | 30 | – | – |
| December | 31 | – | – |
| Year to date (Jan–Jul) | 214 | 257 | ▲ 20.1% |
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 | 81.8% | 80.7% | ▼ 1.4% |
| February | 92.9% | 81.8% | ▼ 11.9% |
| March | 83.9% | 82.8% | ▼ 1.3% |
| April | 93.3% | 96.7% | ▲ 3.6% |
| May | 77.4% | 77.4% | 0.0% |
| June | 90.0% | 80.0% | ▼ 11.1% |
| July | 87.1% | 93.6% | ▲ 7.4% |
| August | 77.4% | – | – |
| September | 93.3% | – | – |
| October | 87.1% | – | in progress |
| November | 96.7% | – | – |
| December | 74.2% | – | – |
| Year-to-date average (Jan–Jul) | 86.6% | 84.7% | ▼ 2.2% |
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 | 0 | 0 | – |
| February | 0 | 1 | – |
| March | 0 | 1 | – |
| April | 0 | 0 | – |
| May | 0 | 0 | – |
| June | 0 | 0 | – |
| July | 0 | 0 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 0 | 2 |
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 99.6% 717
- Cancelled 0.4% 3
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
6| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| ORD DEN Chicago O'Hare International Airport – Denver International Airport | 1,426 | 11.1 min | 86.1% | 187 |
| DEN IAH Denver International Airport – George Bush Intercontinental Airport | 1,387 | 15.9 min | 84.6% | 170 |
| FAR DEN Hector International Airport – Denver International Airport | 1,009 | 18.2 min | 84.6% | 163 |
| MIA DEN Miami International Airport – Denver International Airport | 2,749 | 5.8 min | 91.9% | 37 |
| IAD BDL Washington Dulles International Airport – Bradley International Airport | 523 | -1.5 min | 94.6% | 37 |
| EWR DJT Newark Liberty International Airport – President Donald J. Trump International Airport | 1,650 | 4.4 min | 83.8% | 37 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 35 | 35 | 94.3% | 0 |
| November 2024 | 30 | 30 | 93.3% | 0 |
| December 2024 | 31 | 30 | 63.3% | 1 |
| January 2025 | 33 | 33 | 81.8% | 0 |
| February 2025 | 28 | 28 | 92.9% | 0 |
| March 2025 | 31 | 31 | 83.9% | 0 |
| April 2025 | 30 | 30 | 93.3% | 0 |
| May 2025 | 31 | 31 | 77.4% | 0 |
| June 2025 | 30 | 30 | 90.0% | 0 |
| July 2025 | 31 | 31 | 87.1% | 0 |
| August 2025 | 31 | 31 | 77.4% | 0 |
| September 2025 | 30 | 30 | 93.3% | 0 |
| October 2025 | 31 | 31 | 87.1% | 0 |
| November 2025 | 30 | 30 | 96.7% | 0 |
| December 2025 | 31 | 31 | 74.2% | 0 |
| January 2026 | 31 | 31 | 80.7% | 0 |
| February 2026 | 45 | 44 | 81.8% | 1 |
| March 2026 | 59 | 58 | 82.8% | 1 |
| April 2026 | 30 | 30 | 96.7% | 0 |
| May 2026 | 31 | 31 | 77.4% | 0 |
| June 2026 | 30 | 30 | 80.0% | 0 |
| July 2026 | 31 | 31 | 93.6% | 0 |