WN4123
WN4123 (Southwest Airlines) is a multi-stop service on 17 routes, busiest San Diego to San Jose. Of 226 departures recorded from March 2025 to July 2026, 77.7% left on time, according to the US BTS.
- On-time departures77.7%of 226 flights
- Average delay11.3 min
- July 202626
- Cancelled0.9%
- Legs flown under this number17
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 | – | 5 | – |
| February | – | 3 | – |
| March | 6 | 20 | ▲ 233.3% |
| April | 2 | 26 | ▲ 1,200.0% |
| May | – | 25 | – |
| June | – | 26 | – |
| July | – | 26 | – |
| August | 14 | – | – |
| September | 17 | – | – |
| October | 8 | – | in progress |
| November | 19 | – | – |
| December | 29 | – | – |
according to the US BTS · March 2025 → 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 | – | 80.0% | – |
| February | – | 100.0% | – |
| March | 83.3% | 57.9% | ▼ 30.5% |
| April | 100.0% | 57.7% | ▼ 42.3% |
| May | – | 52.0% | – |
| June | – | 92.3% | – |
| July | – | 96.2% | – |
| August | 92.9% | – | – |
| September | 94.1% | – | – |
| October | 0.0% | – | in progress |
| November | 88.9% | – | – |
| December | 93.1% | – | – |
according to the US BTS · March 2025 → July 2026
Average departure delay by month
Months without data are left blank.
according to the US BTS · March 2025 → 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 | – |
| February | – | 0 | – |
| March | 0 | 1 | – |
| April | 0 | 0 | – |
| May | – | 0 | – |
| June | – | 0 | – |
| July | – | 0 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 1 | – | – |
| December | 0 | – | – |
according to the US BTS · March 2025 → 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 99.1% 224
- Cancelled 0.9% 2
Share of all recorded flights in the period, all legs. · Mar 11, 2025 → Jul 31, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
2| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| SAT PHX San Antonio International Airport – Phoenix Sky Harbor International Airport | 1,354 | 4.0 min | 93.9% | 49 |
| SAN SJC San Diego International Airport – Mineta San Jose International Airport | 671 | 23.1 min | 57.1% | 49 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| March 2025 | 6 | 6 | 83.3% | 0 |
| April 2025 | 2 | 2 | 100.0% | 0 |
| August 2025 | 14 | 14 | 92.9% | 0 |
| September 2025 | 17 | 17 | 94.1% | 0 |
| October 2025 | 8 | 8 | 0.0% | 0 |
| November 2025 | 19 | 18 | 88.9% | 1 |
| December 2025 | 29 | 29 | 93.1% | 0 |
| January 2026 | 5 | 5 | 80.0% | 0 |
| February 2026 | 3 | 3 | 100.0% | 0 |
| March 2026 | 20 | 19 | 57.9% | 1 |
| April 2026 | 26 | 26 | 57.7% | 0 |
| May 2026 | 25 | 25 | 52.0% | 0 |
| June 2026 | 26 | 26 | 92.3% | 0 |
| July 2026 | 26 | 26 | 96.2% | 0 |