WN4643
WN4643 (Southwest Airlines) is a multi-stop service on 14 routes, busiest Chicago to St Louis. Of 274 departures recorded from October 2024 to July 2026, 79.0% left on time, according to the US BTS.
- On-time departures79.0%of 274 flights
- Average delay9.9 min
- July 202623
- Cancelled0.7%
- 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 periods16 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 29 | 1 | ▼ 96.6% |
| February | 27 | 1 | ▼ 96.3% |
| March | 13 | 4 | ▼ 69.2% |
| April | 5 | 25 | ▲ 400.0% |
| May | 4 | 30 | ▲ 650.0% |
| June | 1 | 22 | ▲ 2,100.0% |
| July | – | 23 | – |
| August | – | – | – |
| September | – | – | – |
| October | 30 | – | in progress |
| November | 4 | – | – |
| December | 2 | – | – |
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 periods16 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 69.0% | 100.0% | ▲ 45.0% |
| February | 85.2% | 100.0% | ▲ 17.4% |
| March | 69.2% | 0.0% | ▼ 100.0% |
| April | 100.0% | 100.0% | 0.0% |
| May | 75.0% | 93.3% | ▲ 24.4% |
| June | 100.0% | 50.0% | ▼ 50.0% |
| July | – | 52.2% | – |
| August | – | – | – |
| September | – | – | – |
| October | 100.0% | – | in progress |
| November | 50.0% | – | – |
| December | 50.0% | – | – |
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 periods16 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 0 | 0 | – |
| February | 0 | 0 | – |
| March | 0 | 0 | – |
| April | 0 | 0 | – |
| May | 0 | 0 | – |
| June | 0 | 2 | – |
| July | – | 0 | – |
| 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 99.3% 272
- Cancelled 0.7% 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
4| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| MDW STL Chicago Midway International Airport – St. Louis Lambert International Airport | 404 | 7.1 min | 79.6% | 108 |
| MSY PHX Louis Armstrong New Orleans International Airport – Phoenix Sky Harbor International Airport | 2,088 | 4.0 min | 96.5% | 57 |
| MDW MSP Chicago Midway International Airport – Minneapolis–Saint Paul International Airport / Wold–Chamberlain Field | 560 | 25.7 min | 47.5% | 42 |
| SAT BNA San Antonio International Airport – Nashville International Airport | 1,322 | -2.1 min | 100.0% | 31 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 3 | 3 | 100.0% | 0 |
| November 2024 | 24 | 24 | 87.5% | 0 |
| December 2024 | 26 | 26 | 76.9% | 0 |
| January 2025 | 29 | 29 | 69.0% | 0 |
| February 2025 | 27 | 27 | 85.2% | 0 |
| March 2025 | 13 | 13 | 69.2% | 0 |
| April 2025 | 5 | 5 | 100.0% | 0 |
| May 2025 | 4 | 4 | 75.0% | 0 |
| June 2025 | 1 | 1 | 100.0% | 0 |
| October 2025 | 30 | 30 | 100.0% | 0 |
| November 2025 | 4 | 4 | 50.0% | 0 |
| December 2025 | 2 | 2 | 50.0% | 0 |
| January 2026 | 1 | 1 | 100.0% | 0 |
| February 2026 | 1 | 1 | 100.0% | 0 |
| March 2026 | 4 | 4 | 0.0% | 0 |
| April 2026 | 25 | 25 | 100.0% | 0 |
| May 2026 | 30 | 30 | 93.3% | 0 |
| June 2026 | 22 | 20 | 50.0% | 2 |
| July 2026 | 23 | 23 | 52.2% | 0 |