WN4540
WN4540 (Southwest Airlines) is a multi-stop service on 17 routes, busiest Las Vegas to San Diego. Of 310 departures recorded from October 2024 to July 2026, 61.9% left on time, according to the US BTS.
- On-time departures61.9%of 310 flights
- Average delay19.4 min
- July 202630▲ 650.0%vs July 2025
- Cancelled1.0%
- 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 periods17 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 32 | 6 | ▼ 81.3% |
| February | 22 | 1 | ▼ 95.5% |
| March | 9 | – | – |
| April | 1 | 11 | ▲ 1,000.0% |
| May | – | 13 | – |
| June | 4 | 29 | ▲ 625.0% |
| July | 4 | 30 | ▲ 650.0% |
| August | 5 | – | – |
| September | 4 | – | – |
| October | 13 | – | in progress |
| November | 24 | – | – |
| 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 periods17 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 77.4% | 50.0% | ▼ 35.4% |
| February | 86.4% | 0.0% | ▼ 100.0% |
| March | 66.7% | – | – |
| April | 0.0% | 45.5% | – |
| May | – | 23.1% | – |
| June | 25.0% | 48.3% | ▲ 93.1% |
| July | 25.0% | 70.0% | ▲ 180.0% |
| August | 20.0% | – | – |
| September | 0.0% | – | – |
| October | 100.0% | – | in progress |
| November | 58.3% | – | – |
| 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 periods17 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 1 | 0 | ▼ 100.0% |
| February | 0 | 0 | – |
| March | 0 | – | – |
| April | 0 | 0 | – |
| May | – | 0 | – |
| June | 0 | 0 | – |
| July | 0 | 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 99.0% 307
- Cancelled 1.0% 3
Share of all recorded flights in the period, all legs. · Oct 31, 2024 → Jul 31, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
4| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| LAS SAN Harry Reid International Airport – San Diego International Airport | 417 | 12.2 min | 76.3% | 95 |
| LAS BUR Harry Reid International Airport – Hollywood Burbank/Bob Hope Airport | 359 | 23.1 min | 53.1% | 49 |
| ONT SJC Ontario International Airport – Mineta San Jose International Airport | 536 | 23.7 min | 60.0% | 40 |
| SAN SMF San Diego International Airport – Sacramento International Airport | 773 | 19.8 min | 58.8% | 35 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 1 | 1 | 100.0% | 0 |
| November 2024 | 40 | 40 | 62.5% | 0 |
| December 2024 | 35 | 33 | 63.6% | 2 |
| January 2025 | 32 | 31 | 77.4% | 1 |
| February 2025 | 22 | 22 | 86.4% | 0 |
| March 2025 | 9 | 9 | 66.7% | 0 |
| April 2025 | 1 | 1 | 0.0% | 0 |
| June 2025 | 4 | 4 | 25.0% | 0 |
| July 2025 | 4 | 4 | 25.0% | 0 |
| August 2025 | 5 | 5 | 20.0% | 0 |
| September 2025 | 4 | 4 | 0.0% | 0 |
| October 2025 | 13 | 13 | 100.0% | 0 |
| November 2025 | 24 | 24 | 58.3% | 0 |
| December 2025 | 26 | 26 | 69.2% | 0 |
| January 2026 | 6 | 6 | 50.0% | 0 |
| February 2026 | 1 | 1 | 0.0% | 0 |
| April 2026 | 11 | 11 | 45.5% | 0 |
| May 2026 | 13 | 13 | 23.1% | 0 |
| June 2026 | 29 | 29 | 48.3% | 0 |
| July 2026 | 30 | 30 | 70.0% | 0 |