WN4837
WN4837 (Southwest Airlines) is a multi-stop service on 12 routes, busiest Las Vegas to San Jose. Of 252 departures recorded from October 2024 to July 2026, 79.2% left on time, according to the US BTS.
- On-time departures79.2%of 252 flights
- Average delay13.3 min
- July 202623
- Cancelled0.8%
- Legs flown under this number12
Recorded departures by month
All legs under this number combined; see the leg table.
Months without data are left blank.
The most recent periods14 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 25 | 11 | ▼ 56.0% |
| February | 24 | 19 | ▼ 20.8% |
| March | 26 | 2 | ▼ 92.3% |
| April | 6 | 3 | ▼ 50.0% |
| May | – | 4 | – |
| June | – | 19 | – |
| July | – | 23 | – |
| August | – | – | – |
| September | – | – | – |
| October | 25 | – | in progress |
| November | 3 | – | – |
| December | 9 | – | – |
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 periods14 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 84.0% | 72.7% | ▼ 13.4% |
| February | 87.0% | 63.2% | ▼ 27.4% |
| March | 80.8% | 50.0% | ▼ 38.1% |
| April | 66.7% | 100.0% | ▲ 50.0% |
| May | – | 100.0% | – |
| June | – | 63.2% | – |
| July | – | 72.7% | – |
| August | – | – | – |
| September | – | – | – |
| October | 84.0% | – | in progress |
| November | 66.7% | – | – |
| December | 44.4% | – | – |
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 periods14 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 0 | 0 | – |
| February | 1 | 0 | ▼ 100.0% |
| March | 0 | 0 | – |
| April | 0 | 0 | – |
| May | – | 0 | – |
| June | – | 0 | – |
| July | – | 1 | – |
| August | – | – | – |
| September | – | – | – |
| 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 99.2% 250
- Cancelled 0.8% 2
Share of all recorded flights in the period, all legs. · Oct 13, 2024 → Jul 31, 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 |
|---|---|---|---|---|
| LAS SJC Harry Reid International Airport – Mineta San Jose International Airport | 620 | 7.2 min | 87.0% | 93 |
| PHL MDW Philadelphia International Airport – Chicago Midway International Airport | 1,073 | 29.3 min | 68.3% | 42 |
| SLC DEN Salt Lake City International Airport – Denver International Airport | 628 | 15.9 min | 63.3% | 30 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 10 | 10 | 100.0% | 0 |
| November 2024 | 23 | 23 | 87.0% | 0 |
| December 2024 | 20 | 20 | 95.0% | 0 |
| January 2025 | 25 | 25 | 84.0% | 0 |
| February 2025 | 24 | 23 | 87.0% | 1 |
| March 2025 | 26 | 26 | 80.8% | 0 |
| April 2025 | 6 | 6 | 66.7% | 0 |
| October 2025 | 25 | 25 | 84.0% | 0 |
| November 2025 | 3 | 3 | 66.7% | 0 |
| December 2025 | 9 | 9 | 44.4% | 0 |
| January 2026 | 11 | 11 | 72.7% | 0 |
| February 2026 | 19 | 19 | 63.2% | 0 |
| March 2026 | 2 | 2 | 50.0% | 0 |
| April 2026 | 3 | 3 | 100.0% | 0 |
| May 2026 | 4 | 4 | 100.0% | 0 |
| June 2026 | 19 | 19 | 63.2% | 0 |
| July 2026 | 23 | 22 | 72.7% | 1 |