UA520
UA520 (United Airlines) is a multi-stop service on 20 routes, busiest Houston to Chicago. Of 764 departures recorded from October 2024 to July 2026, 77.4% left on time, according to the US BTS.
- On-time departures77.4%of 764 flights
- Average delay16.0 min
- July 202652▲ 67.7%vs July 2025
- Cancelled0.5%
- Legs flown under this number20
according to the US BTS · Oct 12, 2024 → Jul 31, 2026 domestic flights only
Recorded departures by month
Partial coverage: domestic flights only · 22 of 22 periods have data
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 | 31 | 83 | ▲ 167.7% |
| February | 28 | 55 | ▲ 96.4% |
| March | 31 | 32 | ▲ 3.2% |
| April | 30 | 30 | 0.0% |
| May | 31 | 42 | ▲ 35.5% |
| June | 30 | 55 | ▲ 83.3% |
| July | 31 | 52 | ▲ 67.7% |
| August | 31 | – | – |
| September | 24 | – | – |
| October | 6 | – | in progress |
| November | 30 | – | – |
| December | 31 | – | – |
| Year to date (Jan–Jul) | 212 | 349 | ▲ 64.6% |
according to the US BTS · October 2024 → July 2026
On-time departures by month
Partial coverage: domestic flights only · 22 of 22 periods have data
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 | 77.4% | 89.2% | ▲ 15.2% |
| February | 82.1% | 88.9% | ▲ 8.2% |
| March | 67.7% | 84.4% | ▲ 24.6% |
| April | 66.7% | 80.0% | ▲ 20.0% |
| May | 48.4% | 57.1% | ▲ 18.1% |
| June | 51.7% | 81.8% | ▲ 58.2% |
| July | 54.8% | 80.8% | ▲ 47.3% |
| August | 86.7% | – | – |
| September | 91.7% | – | – |
| October | 50.0% | – | in progress |
| November | 90.0% | – | – |
| December | 90.3% | – | – |
| Year-to-date average (Jan–Jul) | 64.1% | 80.3% | ▲ 25.2% |
according to the US BTS · October 2024 → July 2026
Average departure delay by month
Partial coverage: domestic flights only · 22 of 22 periods have data
according to the US BTS · October 2024 → July 2026
Cancelled departures by month
Partial coverage: domestic flights only · 22 of 22 periods have data
The most recent periods19 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 0 | 0 | – |
| February | 0 | 1 | – |
| March | 0 | 0 | – |
| April | 0 | 0 | – |
| May | 0 | 0 | – |
| June | 1 | 0 | ▼ 100.0% |
| July | 0 | 0 | – |
| August | 1 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 1 | 1 | 0.0% |
according to the US BTS · October 2024 → July 2026
This is not a forecast
This is a historical record of departures already flown, not a forecast for your flight.
This number flies several legs
Several legs: the headline figure averages all of them. See the leg table.
Cancellation share
- Not cancelled 99.5% 760
- Cancelled 0.5% 4
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
99 of 9
| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| IAH ORD George Bush Intercontinental Airport – Chicago O'Hare International Airport | 1,491 | 41.4 min | 59.2% | 166 |
| SFO MCO San Francisco International Airport – Orlando International Airport | 3,929 | 11.6 min | 74.6% | 130 |
| PHX ORD Phoenix Sky Harbor International Airport – Chicago O'Hare International Airport | 2,313 | 5.4 min | 88.9% | 90 |
| LAX SFO Los Angeles International Airport – San Francisco International Airport | 543 | 6.0 min | 85.4% | 89 |
| SFO PHX San Francisco International Airport – Phoenix Sky Harbor International Airport | 1,047 | 4.2 min | 91.9% | 37 |
| EWR SLC Newark Liberty International Airport – Salt Lake City International Airport | 3,160 | 12.8 min | 81.1% | 37 |
| DEN RIC Denver International Airport – Richmond International Airport | 2,379 | 6.0 min | 86.5% | 37 |
| SFO PHL San Francisco International Airport – Philadelphia International Airport | 4,048 | 7.7 min | 80.6% | 36 |
| SAN SFO San Diego International Airport – San Francisco International Airport | 719 | 20.8 min | 76.7% | 30 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 20 | 20 | 85.0% | 0 |
| November 2024 | 30 | 30 | 80.0% | 0 |
| December 2024 | 31 | 30 | 73.3% | 1 |
| January 2025 | 31 | 31 | 77.4% | 0 |
| February 2025 | 28 | 28 | 82.1% | 0 |
| March 2025 | 31 | 31 | 67.7% | 0 |
| April 2025 | 30 | 30 | 66.7% | 0 |
| May 2025 | 31 | 31 | 48.4% | 0 |
| June 2025 | 30 | 29 | 51.7% | 1 |
| July 2025 | 31 | 31 | 54.8% | 0 |
| August 2025 | 31 | 30 | 86.7% | 1 |
| September 2025 | 24 | 24 | 91.7% | 0 |
| October 2025 | 6 | 6 | 50.0% | 0 |
| November 2025 | 30 | 30 | 90.0% | 0 |
| December 2025 | 31 | 31 | 90.3% | 0 |
| January 2026 | 83 | 83 | 89.2% | 0 |
| February 2026 | 55 | 54 | 88.9% | 1 |
| March 2026 | 32 | 32 | 84.4% | 0 |
| April 2026 | 30 | 30 | 80.0% | 0 |
| May 2026 | 42 | 42 | 57.1% | 0 |
| June 2026 | 55 | 55 | 81.8% | 0 |
| July 2026 | 52 | 52 | 80.8% | 0 |