WN4251
WN4251 (Southwest Airlines) is a multi-stop service on 14 routes, busiest Nashville to Austin. Of 381 departures recorded from October 2024 to July 2026, 69.1% left on time, according to the US BTS.
- On-time departures69.1%of 381 flights
- Average delay17.9 min
- July 20269▲ 125.0%vs July 2025
- Cancelled0.5%
- Legs flown under this number14
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 | 27 | 31 | ▲ 14.8% |
| February | 26 | 28 | ▲ 7.7% |
| March | 31 | 31 | 0.0% |
| April | 7 | 6 | ▼ 14.3% |
| May | – | – | – |
| June | 4 | 9 | ▲ 125.0% |
| July | 4 | 9 | ▲ 125.0% |
| August | 27 | – | – |
| September | 30 | – | – |
| October | 1 | – | in progress |
| November | 26 | – | – |
| December | 29 | – | – |
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 | 70.4% | 72.4% | ▲ 2.9% |
| February | 84.6% | 92.9% | ▲ 9.7% |
| March | 83.9% | 64.5% | ▼ 23.1% |
| April | 71.4% | 50.0% | ▼ 30.0% |
| May | – | – | – |
| June | 100.0% | 88.9% | ▼ 11.1% |
| July | 100.0% | 77.8% | ▼ 22.2% |
| August | 48.2% | – | – |
| September | 43.3% | – | – |
| October | 100.0% | – | in progress |
| November | 46.2% | – | – |
| December | 55.2% | – | – |
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 | 0 | 2 | – |
| February | 0 | 0 | – |
| March | 0 | 0 | – |
| April | 0 | 0 | – |
| May | – | – | – |
| 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 99.5% 379
- Cancelled 0.5% 2
Share of all recorded flights in the period, all legs. · Oct 12, 2024 → Jul 26, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
6| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| BNA AUS Nashville International Airport – Austin Bergstrom International Airport | 1,215 | 7.4 min | 81.1% | 74 |
| SFO DEN San Francisco International Airport – Denver International Airport | 1,553 | 40.3 min | 46.7% | 60 |
| DEN LIT Denver International Airport – Bill & Hillary Clinton National Airport/Adams Field | 1,239 | 2.7 min | 91.1% | 58 |
| SEA DAL Seattle–Tacoma International Airport – Dallas Love Field | 2,685 | 27.1 min | 45.6% | 57 |
| SAN SJC San Diego International Airport – Mineta San Jose International Airport | 671 | 22.8 min | 57.6% | 33 |
| MKE RSW General Mitchell International Airport – Southwest Florida International Airport | 1,908 | 15.4 min | 84.9% | 33 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 17 | 17 | 76.5% | 0 |
| November 2024 | 14 | 14 | 85.7% | 0 |
| December 2024 | 24 | 24 | 70.8% | 0 |
| January 2025 | 27 | 27 | 70.4% | 0 |
| February 2025 | 26 | 26 | 84.6% | 0 |
| March 2025 | 31 | 31 | 83.9% | 0 |
| April 2025 | 7 | 7 | 71.4% | 0 |
| June 2025 | 4 | 4 | 100.0% | 0 |
| July 2025 | 4 | 4 | 100.0% | 0 |
| August 2025 | 27 | 27 | 48.2% | 0 |
| September 2025 | 30 | 30 | 43.3% | 0 |
| October 2025 | 1 | 1 | 100.0% | 0 |
| November 2025 | 26 | 26 | 46.2% | 0 |
| December 2025 | 29 | 29 | 55.2% | 0 |
| January 2026 | 31 | 29 | 72.4% | 2 |
| February 2026 | 28 | 28 | 92.9% | 0 |
| March 2026 | 31 | 31 | 64.5% | 0 |
| April 2026 | 6 | 6 | 50.0% | 0 |
| June 2026 | 9 | 9 | 88.9% | 0 |
| July 2026 | 9 | 9 | 77.8% | 0 |