WN4231
WN4231 (Southwest Airlines) is a multi-stop service on 15 routes, busiest Denver to Sacramento. Of 312 departures recorded from October 2024 to July 2026, 82.4% left on time, according to the US BTS.
- On-time departures82.4%of 312 flights
- Average delay8.8 min
- July 202621
- Cancelled0.0%
- Legs flown under this number15
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 | 27 | 4 | ▼ 85.2% |
| February | 20 | 2 | ▼ 90.0% |
| March | 30 | – | – |
| April | 7 | 24 | ▲ 242.9% |
| May | 1 | 31 | ▲ 3,000.0% |
| June | – | 23 | – |
| July | – | 21 | – |
| August | 19 | – | – |
| September | 22 | – | – |
| October | 1 | – | in progress |
| November | 25 | – | – |
| December | 26 | – | – |
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 | 81.5% | 75.0% | ▼ 8.0% |
| February | 80.0% | 100.0% | ▲ 25.0% |
| March | 86.7% | – | – |
| April | 85.7% | 75.0% | ▼ 12.5% |
| May | 100.0% | 83.9% | ▼ 16.1% |
| June | – | 82.6% | – |
| July | – | 95.2% | – |
| August | 84.2% | – | – |
| September | 90.9% | – | – |
| October | 100.0% | – | in progress |
| November | 88.0% | – | – |
| December | 69.2% | – | – |
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 | 0 | 0 | – |
| February | 0 | 0 | – |
| March | 0 | – | – |
| April | 0 | 0 | – |
| May | 0 | 0 | – |
| June | – | 0 | – |
| July | – | 0 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| 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 100.0% 312
- Cancelled 0.0% 0
Share of all recorded flights in the period, all legs. · Oct 15, 2024 → Jul 31, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
5| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| DEN SMF Denver International Airport – Sacramento International Airport | 1,460 | 13.0 min | 77.0% | 74 |
| SJC BWI Mineta San Jose International Airport – Baltimore/Washington International Thurgood Marshall Airport | 3,915 | 7.1 min | 79.3% | 58 |
| SAT BWI San Antonio International Airport – Baltimore/Washington International Thurgood Marshall Airport | 2,262 | 1.8 min | 88.1% | 42 |
| SFO LAS San Francisco International Airport – Harry Reid International Airport | 665 | 4.2 min | 90.2% | 41 |
| ELP HOU El Paso International Airport – William P. Hobby Airport | 1,087 | 9.8 min | 84.9% | 33 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 6 | 6 | 100.0% | 0 |
| November 2024 | 9 | 9 | 77.8% | 0 |
| December 2024 | 14 | 14 | 57.1% | 0 |
| January 2025 | 27 | 27 | 81.5% | 0 |
| February 2025 | 20 | 20 | 80.0% | 0 |
| March 2025 | 30 | 30 | 86.7% | 0 |
| April 2025 | 7 | 7 | 85.7% | 0 |
| May 2025 | 1 | 1 | 100.0% | 0 |
| August 2025 | 19 | 19 | 84.2% | 0 |
| September 2025 | 22 | 22 | 90.9% | 0 |
| October 2025 | 1 | 1 | 100.0% | 0 |
| November 2025 | 25 | 25 | 88.0% | 0 |
| December 2025 | 26 | 26 | 69.2% | 0 |
| January 2026 | 4 | 4 | 75.0% | 0 |
| February 2026 | 2 | 2 | 100.0% | 0 |
| April 2026 | 24 | 24 | 75.0% | 0 |
| May 2026 | 31 | 31 | 83.9% | 0 |
| June 2026 | 23 | 23 | 82.6% | 0 |
| July 2026 | 21 | 21 | 95.2% | 0 |