WN400
WN400 (Southwest Airlines) is a multi-stop service on 32 routes, busiest Chicago to Atlanta. Of 649 departures recorded from October 2024 to July 2026, 69.0% left on time, according to the US BTS.
- On-time departures69.0%of 649 flights
- Average delay16.5 min
- July 202629▼ 17.1%vs July 2025
- Cancelled1.2%
- Legs flown under this number32
Recorded departures by month
All legs under this number combined; see the leg table.
The most recent periods19 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 32 | 31 | ▼ 3.1% |
| February | 27 | 28 | ▲ 3.7% |
| March | 31 | 31 | 0.0% |
| April | 27 | 30 | ▲ 11.1% |
| May | 25 | 30 | ▲ 20.0% |
| June | 34 | 26 | ▼ 23.5% |
| July | 35 | 29 | ▼ 17.1% |
| August | 21 | – | – |
| September | 17 | – | – |
| October | 31 | – | in progress |
| November | 32 | – | – |
| December | 31 | – | – |
| Year to date (Jan–Jul) | 211 | 205 | ▼ 2.8% |
according to the US BTS · October 2024 → July 2026
On-time departures by month
On time = departure within 15 minutes of schedule. Non-cancelled flights with a recorded delay only.
The most recent periods19 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 75.9% | 74.2% | ▼ 2.2% |
| February | 74.1% | 75.0% | ▲ 1.3% |
| March | 93.3% | 66.7% | ▼ 28.6% |
| April | 66.7% | 51.7% | ▼ 22.4% |
| May | 68.0% | 36.7% | ▼ 46.1% |
| June | 58.8% | 34.6% | ▼ 41.1% |
| July | 58.8% | 50.0% | ▼ 15.0% |
| August | 85.7% | – | – |
| September | 100.0% | – | – |
| October | 83.9% | – | in progress |
| November | 53.1% | – | – |
| December | 64.5% | – | – |
| Year-to-date average (Jan–Jul) | 70.8% | 55.6% | ▼ 21.5% |
according to the US BTS · October 2024 → July 2026
Average departure delay by month
according to the US BTS · October 2024 → July 2026
Cancelled departures by month
The most recent periods19 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 3 | 0 | ▼ 100.0% |
| February | 0 | 0 | – |
| March | 1 | 1 | 0.0% |
| April | 0 | 1 | – |
| May | 0 | 0 | – |
| June | 0 | 0 | – |
| July | 1 | 1 | 0.0% |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 5 | 3 | ▼ 40.0% |
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 98.8% 641
- Cancelled 1.2% 8
Share of all recorded flights in the period, all legs. · Oct 12, 2024 → Jul 31, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
10Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 23 | 23 | 87.0% | 0 |
| November 2024 | 44 | 44 | 93.2% | 0 |
| December 2024 | 34 | 34 | 73.5% | 0 |
| January 2025 | 32 | 29 | 75.9% | 3 |
| February 2025 | 27 | 27 | 74.1% | 0 |
| March 2025 | 31 | 30 | 93.3% | 1 |
| April 2025 | 27 | 27 | 66.7% | 0 |
| May 2025 | 25 | 25 | 68.0% | 0 |
| June 2025 | 34 | 34 | 58.8% | 0 |
| July 2025 | 35 | 34 | 58.8% | 1 |
| August 2025 | 21 | 21 | 85.7% | 0 |
| September 2025 | 17 | 17 | 100.0% | 0 |
| October 2025 | 31 | 31 | 83.9% | 0 |
| November 2025 | 32 | 32 | 53.1% | 0 |
| December 2025 | 31 | 31 | 64.5% | 0 |
| January 2026 | 31 | 31 | 74.2% | 0 |
| February 2026 | 28 | 28 | 75.0% | 0 |
| March 2026 | 31 | 30 | 66.7% | 1 |
| April 2026 | 30 | 29 | 51.7% | 1 |
| May 2026 | 30 | 30 | 36.7% | 0 |
| June 2026 | 26 | 26 | 34.6% | 0 |
| July 2026 | 29 | 28 | 50.0% | 1 |