WN427
WN427 (Southwest Airlines) is a multi-stop service on 48 routes, busiest San Jose to Denver. Of 801 departures recorded from October 2024 to July 2026, 71.8% left on time, according to the US BTS.
- On-time departures71.8%of 801 flights
- Average delay17.6 min
- July 202671▲ 102.9%vs July 2025
- Cancelled0.8%
- Legs flown under this number48
according to the US BTS · Oct 13, 2024 → Jul 31, 2026 domestic flights only
Recorded departures by month
Partial coverage: domestic flights only · 22 of 22 periods have data
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 | 40 | 29 | ▼ 27.5% |
| February | 30 | 28 | ▼ 6.7% |
| March | 31 | 38 | ▲ 22.6% |
| April | 7 | 41 | ▲ 485.7% |
| May | 1 | 44 | ▲ 4,300.0% |
| June | 30 | 65 | ▲ 116.7% |
| July | 35 | 71 | ▲ 102.9% |
| August | 53 | – | – |
| September | 55 | – | – |
| October | 14 | – | in progress |
| November | 21 | – | – |
| December | 17 | – | – |
| Year to date (Jan–Jul) | 174 | 316 | ▲ 81.6% |
according to the US BTS · October 2024 → July 2026
On-time departures by month
Partial coverage: domestic flights only · 22 of 22 periods have data
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 | 80.0% | 82.1% | ▲ 2.7% |
| February | 75.9% | 74.1% | ▼ 2.4% |
| March | 87.1% | 56.8% | ▼ 34.8% |
| April | 57.1% | 43.9% | ▼ 23.2% |
| May | 100.0% | 38.6% | ▼ 61.4% |
| June | 66.7% | 78.1% | ▲ 17.2% |
| July | 68.6% | 66.2% | ▼ 3.5% |
| August | 75.5% | – | – |
| September | 80.0% | – | – |
| October | 71.4% | – | in progress |
| November | 47.6% | – | – |
| December | 23.5% | – | – |
| Year-to-date average (Jan–Jul) | 76.5% | 62.8% | ▼ 17.8% |
according to the US BTS · October 2024 → July 2026
Average departure delay by month
Partial coverage: domestic flights only · 22 of 22 periods have data
according to the US BTS · October 2024 → July 2026
Cancelled departures by month
Partial coverage: domestic flights only · 22 of 22 periods have data
The most recent periods19 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 0 | 1 | – |
| February | 1 | 1 | 0.0% |
| March | 0 | 1 | – |
| April | 0 | 0 | – |
| May | 0 | 0 | – |
| June | 0 | 1 | – |
| July | 0 | 0 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 1 | 4 | ▲ 300.0% |
according to the US BTS · October 2024 → July 2026
This is not a forecast
This is a historical record of departures already flown, not a forecast for your flight.
This number flies several legs
Several legs: the headline figure averages all of them. See the leg table.
Cancellation share
- Not cancelled 99.3% 795
- Cancelled 0.7% 6
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
88 of 8
| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| SJC DEN Mineta San Jose International Airport – Denver International Airport | 1,522 | 23.4 min | 48.3% | 58 |
| BWI BDL Baltimore/Washington International Thurgood Marshall Airport – Bradley International Airport | 455 | 25.6 min | 74.1% | 58 |
| OAK BUR Oakland San Francisco Bay Airport – Hollywood Burbank/Bob Hope Airport | 523 | 6.0 min | 82.7% | 53 |
| PNS BNA Pensacola International Airport – Nashville International Airport | 630 | 15.2 min | 70.6% | 51 |
| BDL MDW Bradley International Airport – Chicago Midway International Airport | 1,246 | 47.0 min | 69.1% | 42 |
| PHX OAK Phoenix Sky Harbor International Airport – Oakland San Francisco Bay Airport | 1,039 | 38.2 min | 33.3% | 39 |
| STL DTW St. Louis Lambert International Airport – Detroit Metropolitan Wayne County Airport | 707 | 3.9 min | 93.6% | 31 |
| DTW LAS Detroit Metropolitan Wayne County Airport – Harry Reid International Airport | 2,808 | 7.8 min | 83.9% | 31 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 25 | 25 | 100.0% | 0 |
| November 2024 | 52 | 52 | 98.1% | 0 |
| December 2024 | 74 | 73 | 83.6% | 1 |
| January 2025 | 40 | 40 | 80.0% | 0 |
| February 2025 | 30 | 29 | 75.9% | 1 |
| March 2025 | 31 | 31 | 87.1% | 0 |
| April 2025 | 7 | 7 | 57.1% | 0 |
| May 2025 | 1 | 1 | 100.0% | 0 |
| June 2025 | 30 | 30 | 66.7% | 0 |
| July 2025 | 35 | 35 | 68.6% | 0 |
| August 2025 | 53 | 53 | 75.5% | 0 |
| September 2025 | 55 | 55 | 80.0% | 0 |
| October 2025 | 14 | 14 | 71.4% | 0 |
| November 2025 | 21 | 21 | 47.6% | 0 |
| December 2025 | 17 | 17 | 23.5% | 0 |
| January 2026 | 29 | 28 | 82.1% | 1 |
| February 2026 | 28 | 27 | 74.1% | 1 |
| March 2026 | 38 | 37 | 56.8% | 1 |
| April 2026 | 41 | 41 | 43.9% | 0 |
| May 2026 | 44 | 44 | 38.6% | 0 |
| June 2026 | 65 | 64 | 78.1% | 1 |
| July 2026 | 71 | 71 | 66.2% | 0 |