WN851
WN851 (Southwest Airlines) is a multi-stop service on 35 routes, busiest Las Vegas to Atlanta. Of 641 departures recorded from October 2024 to July 2026, 75.1% left on time, according to the US BTS.
- On-time departures75.1%of 641 flights
- Average delay13.2 min
- July 202637▲ 27.6%vs July 2025
- Cancelled0.9%
- Legs flown under this number35
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 | 28 | 31 | ▲ 10.7% |
| February | 23 | 28 | ▲ 21.7% |
| March | 34 | 38 | ▲ 11.8% |
| April | 31 | 21 | ▼ 32.3% |
| May | 31 | 17 | ▼ 45.2% |
| June | 26 | 37 | ▲ 42.3% |
| July | 29 | 37 | ▲ 27.6% |
| August | 29 | – | – |
| September | 29 | – | – |
| October | 31 | – | in progress |
| November | 30 | – | – |
| December | 31 | – | – |
| Year to date (Jan–Jul) | 202 | 209 | ▲ 3.5% |
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 | 81.5% | 83.3% | ▲ 2.3% |
| February | 91.3% | 76.9% | ▼ 15.8% |
| March | 76.5% | 44.7% | ▼ 41.5% |
| April | 77.4% | 71.4% | ▼ 7.7% |
| May | 73.3% | 29.4% | ▼ 59.9% |
| June | 73.1% | 54.1% | ▼ 26.0% |
| July | 58.6% | 75.7% | ▲ 29.1% |
| August | 86.2% | – | – |
| September | 79.3% | – | – |
| October | 80.7% | – | in progress |
| November | 93.1% | – | – |
| December | 80.7% | – | – |
| Year-to-date average (Jan–Jul) | 76.0% | 62.2% | ▼ 18.1% |
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 | 1 | 1 | 0.0% |
| February | 0 | 2 | – |
| March | 0 | 0 | – |
| April | 0 | 0 | – |
| May | 1 | 0 | ▼ 100.0% |
| June | 0 | 0 | – |
| July | 0 | 0 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 1 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 2 | 3 | ▲ 50.0% |
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 99.1% 635
- Cancelled 0.9% 6
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
7| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| LAS ATL Harry Reid International Airport – Hartsfield Jackson Atlanta International Airport | 2,805 | 6.9 min | 87.3% | 80 |
| HOU MDW William P. Hobby Airport – Chicago Midway International Airport | 1,510 | 5.6 min | 87.3% | 64 |
| MCI STL Kansas City International Airport – St. Louis Lambert International Airport | 380 | 12.3 min | 77.2% | 58 |
| BWI BOS Baltimore/Washington International Thurgood Marshall Airport – Boston Logan International Airport | 594 | 11.9 min | 76.4% | 58 |
| BUR SMF Hollywood Burbank/Bob Hope Airport – Sacramento International Airport | 577 | 9.5 min | 71.9% | 57 |
| DEN ONT Denver International Airport – Ontario International Airport | 1,316 | 22.8 min | 59.6% | 52 |
| MSY DAL Louis Armstrong New Orleans International Airport – Dallas Love Field | 700 | 2.9 min | 91.2% | 34 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 20 | 20 | 80.0% | 0 |
| November 2024 | 28 | 28 | 92.9% | 0 |
| December 2024 | 32 | 32 | 90.6% | 0 |
| January 2025 | 28 | 27 | 81.5% | 1 |
| February 2025 | 23 | 23 | 91.3% | 0 |
| March 2025 | 34 | 34 | 76.5% | 0 |
| April 2025 | 31 | 31 | 77.4% | 0 |
| May 2025 | 31 | 30 | 73.3% | 1 |
| June 2025 | 26 | 26 | 73.1% | 0 |
| July 2025 | 29 | 29 | 58.6% | 0 |
| August 2025 | 29 | 29 | 86.2% | 0 |
| September 2025 | 29 | 29 | 79.3% | 0 |
| October 2025 | 31 | 31 | 80.7% | 0 |
| November 2025 | 30 | 29 | 93.1% | 1 |
| December 2025 | 31 | 31 | 80.7% | 0 |
| January 2026 | 31 | 30 | 83.3% | 1 |
| February 2026 | 28 | 26 | 76.9% | 2 |
| March 2026 | 38 | 38 | 44.7% | 0 |
| April 2026 | 21 | 21 | 71.4% | 0 |
| May 2026 | 17 | 17 | 29.4% | 0 |
| June 2026 | 37 | 37 | 54.1% | 0 |
| July 2026 | 37 | 37 | 75.7% | 0 |