WN1521
WN1521 (Southwest Airlines) is a multi-stop service on 27 routes, busiest Denver to Dallas. Of 599 departures recorded from October 2024 to July 2026, 72.2% left on time, according to the US BTS.
- On-time departures72.2%of 599 flights
- Average delay16.6 min
- July 202636▲ 89.5%vs July 2025
- Cancelled0.8%
- Legs flown under this number27
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 | 10 | 31 | ▲ 210.0% |
| February | 15 | 28 | ▲ 86.7% |
| March | 32 | 20 | ▼ 37.5% |
| April | 40 | 28 | ▼ 30.0% |
| May | 45 | 31 | ▼ 31.1% |
| June | 19 | 34 | ▲ 78.9% |
| July | 19 | 36 | ▲ 89.5% |
| August | 35 | – | – |
| September | 39 | – | – |
| October | 22 | – | in progress |
| November | 30 | – | – |
| December | 31 | – | – |
| Year to date (Jan–Jul) | 180 | 208 | ▲ 15.6% |
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 | 70.0% | 83.9% | ▲ 19.8% |
| February | 46.7% | 96.4% | ▲ 106.6% |
| March | 87.5% | 63.2% | ▼ 27.8% |
| April | 92.3% | 71.4% | ▼ 22.6% |
| May | 88.6% | 53.3% | ▼ 39.8% |
| June | 73.7% | 23.5% | ▼ 68.1% |
| July | 57.9% | 47.2% | ▼ 18.4% |
| August | 51.4% | – | – |
| September | 84.6% | – | – |
| October | 100.0% | – | in progress |
| November | 65.5% | – | – |
| December | 71.0% | – | – |
| Year-to-date average (Jan–Jul) | 73.8% | 62.7% | ▼ 15.0% |
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 | 0 | 0 | – |
| February | 0 | 0 | – |
| March | 0 | 1 | – |
| April | 1 | 0 | ▼ 100.0% |
| May | 1 | 1 | 0.0% |
| June | 0 | 0 | – |
| July | 0 | 0 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 1 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 2 | 2 | 0.0% |
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 99.2% 594
- Cancelled 0.8% 5
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
7| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| DEN DAL Denver International Airport – Dallas Love Field | 1,048 | 35.9 min | 54.3% | 81 |
| SAN OAK San Diego International Airport – Oakland San Francisco Bay Airport | 718 | 15.2 min | 66.7% | 64 |
| DEN MCO Denver International Airport – Orlando International Airport | 2,486 | 0.6 min | 94.8% | 58 |
| ATL DEN Hartsfield Jackson Atlanta International Airport – Denver International Airport | 1,927 | 22.4 min | 66.7% | 51 |
| DAL MSY Dallas Love Field – Louis Armstrong New Orleans International Airport | 700 | 9.4 min | 89.8% | 50 |
| SJC BUR Mineta San Jose International Airport – Hollywood Burbank/Bob Hope Airport | 477 | 11.0 min | 73.5% | 49 |
| MDW PHX Chicago Midway International Airport – Phoenix Sky Harbor International Airport | 2,319 | 8.0 min | 87.9% | 33 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 16 | 16 | 93.8% | 0 |
| November 2024 | 12 | 12 | 100.0% | 0 |
| December 2024 | 26 | 26 | 76.9% | 0 |
| January 2025 | 10 | 10 | 70.0% | 0 |
| February 2025 | 15 | 15 | 46.7% | 0 |
| March 2025 | 32 | 32 | 87.5% | 0 |
| April 2025 | 40 | 39 | 92.3% | 1 |
| May 2025 | 45 | 44 | 88.6% | 1 |
| June 2025 | 19 | 19 | 73.7% | 0 |
| July 2025 | 19 | 19 | 57.9% | 0 |
| August 2025 | 35 | 35 | 51.4% | 0 |
| September 2025 | 39 | 39 | 84.6% | 0 |
| October 2025 | 22 | 22 | 100.0% | 0 |
| November 2025 | 30 | 29 | 65.5% | 1 |
| December 2025 | 31 | 31 | 71.0% | 0 |
| January 2026 | 31 | 31 | 83.9% | 0 |
| February 2026 | 28 | 28 | 96.4% | 0 |
| March 2026 | 20 | 19 | 63.2% | 1 |
| April 2026 | 28 | 28 | 71.4% | 0 |
| May 2026 | 31 | 30 | 53.3% | 1 |
| June 2026 | 34 | 34 | 23.5% | 0 |
| July 2026 | 36 | 36 | 47.2% | 0 |