DL499
DL499 (Delta Air Lines) is a multi-stop service on 2 routes, busiest Boston to Denver. Of 1,286 departures recorded from October 2024 to July 2026, 81.2% left on time, according to the US BTS.
- On-time departures81.2%of 1,286 flights
- Average delay7.8 min
- July 202662▲ 0.0%vs July 2025
- Cancelled1.0%
- Legs flown under this number2
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 | 58 | 58 | 0.0% |
| February | 56 | 56 | 0.0% |
| March | 62 | 62 | 0.0% |
| April | 60 | 60 | 0.0% |
| May | 62 | 62 | 0.0% |
| June | 60 | 60 | 0.0% |
| July | 62 | 62 | 0.0% |
| August | 62 | – | – |
| September | 60 | – | – |
| October | 62 | – | in progress |
| November | 60 | – | – |
| December | 50 | – | – |
| Year to date (Jan–Jul) | 420 | 420 | 0.0% |
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 | 84.5% | 76.8% | ▼ 9.1% |
| February | 57.1% | 94.3% | ▲ 65.1% |
| March | 77.4% | 80.7% | ▲ 4.2% |
| April | 73.3% | 93.3% | ▲ 27.3% |
| May | 87.1% | 93.3% | ▲ 7.2% |
| June | 76.7% | 85.0% | ▲ 10.9% |
| July | 80.0% | 76.7% | ▼ 4.2% |
| August | 93.3% | – | – |
| September | 71.7% | – | – |
| October | 71.0% | – | in progress |
| November | 93.3% | – | – |
| December | 70.0% | – | – |
| Year-to-date average (Jan–Jul) | 76.6% | 85.7% | ▲ 11.9% |
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 | 2 | – |
| February | 0 | 3 | – |
| March | 0 | 0 | – |
| April | 0 | 0 | – |
| May | 0 | 2 | – |
| June | 0 | 0 | – |
| July | 2 | 2 | 0.0% |
| August | 2 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 2 | 9 | ▲ 350.0% |
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 99.0% 1,273
- Cancelled 1.0% 13
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
2| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| BOS DEN Boston Logan International Airport – Denver International Airport | 2,816 | 3.0 min | 87.4% | 658 |
| DEN BOS Denver International Airport – Boston Logan International Airport | 2,816 | 12.8 min | 74.8% | 628 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 40 | 40 | 82.5% | 0 |
| November 2024 | 60 | 60 | 83.3% | 0 |
| December 2024 | 52 | 52 | 84.6% | 0 |
| January 2025 | 58 | 58 | 84.5% | 0 |
| February 2025 | 56 | 56 | 57.1% | 0 |
| March 2025 | 62 | 62 | 77.4% | 0 |
| April 2025 | 60 | 60 | 73.3% | 0 |
| May 2025 | 62 | 62 | 87.1% | 0 |
| June 2025 | 60 | 60 | 76.7% | 0 |
| July 2025 | 62 | 60 | 80.0% | 2 |
| August 2025 | 62 | 60 | 93.3% | 2 |
| September 2025 | 60 | 60 | 71.7% | 0 |
| October 2025 | 62 | 62 | 71.0% | 0 |
| November 2025 | 60 | 60 | 93.3% | 0 |
| December 2025 | 50 | 50 | 70.0% | 0 |
| January 2026 | 58 | 56 | 76.8% | 2 |
| February 2026 | 56 | 53 | 94.3% | 3 |
| March 2026 | 62 | 62 | 80.7% | 0 |
| April 2026 | 60 | 60 | 93.3% | 0 |
| May 2026 | 62 | 60 | 93.3% | 2 |
| June 2026 | 60 | 60 | 85.0% | 0 |
| July 2026 | 62 | 60 | 76.7% | 2 |