WN4036
WN4036 (Southwest Airlines) is a multi-stop service on 21 routes, busiest Phoenix to Denver. Of 268 departures recorded from October 2024 to July 2026, 64.6% left on time, according to the US BTS.
- On-time departures64.6%of 268 flights
- Average delay16.3 min
- July 202616
- Cancelled1.9%
- Legs flown under this number21
Recorded departures by month
All legs under this number combined; see the leg table.
Months without data are left blank.
The most recent periods16 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 3 | 2 | ▼ 33.3% |
| February | 2 | 11 | ▲ 450.0% |
| March | 1 | 24 | ▲ 2,300.0% |
| April | – | 18 | – |
| May | 1 | 18 | ▲ 1,700.0% |
| June | – | 16 | – |
| July | – | 16 | – |
| August | 26 | – | – |
| September | 30 | – | – |
| October | 1 | – | in progress |
| November | 24 | – | – |
| December | 22 | – | – |
according to the US BTS · October 2024 → July 2026
On-time departures by month
Months without data are left blank.
On time = departure within 15 minutes of schedule. Non-cancelled flights with a recorded delay only.
The most recent periods16 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 50.0% | 100.0% | ▲ 100.0% |
| February | 100.0% | 36.4% | ▼ 63.6% |
| March | 100.0% | 58.3% | ▼ 41.7% |
| April | – | 77.8% | – |
| May | 0.0% | 64.7% | – |
| June | – | 68.8% | – |
| July | – | 81.3% | – |
| August | 52.0% | – | – |
| September | 69.0% | – | – |
| October | 100.0% | – | in progress |
| November | 52.2% | – | – |
| December | 31.8% | – | – |
according to the US BTS · October 2024 → July 2026
Average departure delay by month
Months without data are left blank.
according to the US BTS · October 2024 → July 2026
Cancelled departures by month
Months without data are left blank.
The most recent periods16 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 1 | 0 | ▼ 100.0% |
| February | 0 | 0 | – |
| March | 0 | 0 | – |
| April | – | 0 | – |
| May | 0 | 1 | – |
| June | – | 0 | – |
| July | – | 0 | – |
| August | 1 | – | – |
| September | 1 | – | – |
| October | 0 | – | in progress |
| November | 1 | – | – |
| December | 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 98.1% 263
- Cancelled 1.9% 5
Share of all recorded flights in the period, all legs. · Oct 12, 2024 → Jul 29, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
3| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| PHX DEN Phoenix Sky Harbor International Airport – Denver International Airport | 968 | 17.5 min | 64.6% | 50 |
| PHL DEN Philadelphia International Airport – Denver International Airport | 2,501 | 25.3 min | 45.5% | 45 |
| RSW BWI Southwest Florida International Airport – Baltimore/Washington International Thurgood Marshall Airport | 1,483 | 10.1 min | 71.0% | 32 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 20 | 20 | 80.0% | 0 |
| November 2024 | 15 | 15 | 86.7% | 0 |
| December 2024 | 18 | 18 | 83.3% | 0 |
| January 2025 | 3 | 2 | 50.0% | 1 |
| February 2025 | 2 | 2 | 100.0% | 0 |
| March 2025 | 1 | 1 | 100.0% | 0 |
| May 2025 | 1 | 1 | 0.0% | 0 |
| August 2025 | 26 | 25 | 52.0% | 1 |
| September 2025 | 30 | 29 | 69.0% | 1 |
| October 2025 | 1 | 1 | 100.0% | 0 |
| November 2025 | 24 | 23 | 52.2% | 1 |
| December 2025 | 22 | 22 | 31.8% | 0 |
| January 2026 | 2 | 2 | 100.0% | 0 |
| February 2026 | 11 | 11 | 36.4% | 0 |
| March 2026 | 24 | 24 | 58.3% | 0 |
| April 2026 | 18 | 18 | 77.8% | 0 |
| May 2026 | 18 | 17 | 64.7% | 1 |
| June 2026 | 16 | 16 | 68.8% | 0 |
| July 2026 | 16 | 16 | 81.3% | 0 |