UA2104
UA2104 (United Airlines) is a multi-stop service on 19 routes, busiest Chicago to Boston. Of 625 departures recorded from October 2024 to July 2026, 80.1% left on time, according to the US BTS.
- On-time departures80.1%of 625 flights
- Average delay14.4 min
- July 202630▲ 42.9%vs July 2025
- Cancelled1.0%
- Legs flown under this number19
according to the US BTS · Oct 12, 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 | 31 | 53 | ▲ 71.0% |
| February | 28 | 38 | ▲ 35.7% |
| March | 31 | 30 | ▼ 3.2% |
| April | 30 | 26 | ▼ 13.3% |
| May | 29 | 31 | ▲ 6.9% |
| June | 22 | 30 | ▲ 36.4% |
| July | 21 | 30 | ▲ 42.9% |
| August | 24 | – | – |
| September | 21 | – | – |
| October | 22 | – | in progress |
| November | 19 | – | – |
| December | 28 | – | – |
| Year to date (Jan–Jul) | 192 | 238 | ▲ 24.0% |
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 | 61.3% | 82.4% | ▲ 34.4% |
| February | 55.6% | 91.9% | ▲ 65.4% |
| March | 54.8% | 83.3% | ▲ 52.0% |
| April | 80.0% | 96.2% | ▲ 20.2% |
| May | 62.1% | 96.8% | ▲ 55.9% |
| June | 90.9% | 90.0% | ▼ 1.0% |
| July | 85.7% | 53.6% | ▼ 37.5% |
| August | 95.8% | – | – |
| September | 90.5% | – | – |
| October | 100.0% | – | in progress |
| November | 100.0% | – | – |
| December | 71.4% | – | – |
| Year-to-date average (Jan–Jul) | 70.1% | 84.9% | ▲ 21.1% |
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 | 2 | – |
| February | 1 | 1 | 0.0% |
| March | 0 | 0 | – |
| April | 0 | 0 | – |
| May | 0 | 0 | – |
| June | 0 | 0 | – |
| July | 0 | 2 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 1 | 5 | ▲ 400.0% |
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 99.0% 619
- Cancelled 1.0% 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
88 of 8
| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| ORD BOS Chicago O'Hare International Airport – Boston Logan International Airport | 1,391 | -0.4 min | 94.5% | 163 |
| DCA DEN Ronald Reagan Washington National Airport – Denver International Airport | 2,369 | 27.8 min | 64.4% | 87 |
| JAX DEN Jacksonville International Airport – Denver International Airport | 2,325 | 35.1 min | 67.9% | 53 |
| ORD SLC Chicago O'Hare International Airport – Salt Lake City International Airport | 2,006 | 4.7 min | 89.2% | 37 |
| EWR SNA Newark Liberty International Airport – John Wayne Orange County International Airport | 3,908 | -0.5 min | 94.4% | 37 |
| EWR CLT Newark Liberty International Airport – Charlotte Douglas International Airport | 850 | 49.4 min | 61.8% | 36 |
| STL EWR St. Louis Lambert International Airport – Newark Liberty International Airport | 1,400 | 4.2 min | 88.2% | 34 |
| SAV EWR Savannah Hilton Head International Airport – Newark Liberty International Airport | 1,140 | 19.4 min | 74.2% | 32 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 20 | 20 | 75.0% | 0 |
| November 2024 | 30 | 30 | 86.7% | 0 |
| December 2024 | 31 | 31 | 74.2% | 0 |
| January 2025 | 31 | 31 | 61.3% | 0 |
| February 2025 | 28 | 27 | 55.6% | 1 |
| March 2025 | 31 | 31 | 54.8% | 0 |
| April 2025 | 30 | 30 | 80.0% | 0 |
| May 2025 | 29 | 29 | 62.1% | 0 |
| June 2025 | 22 | 22 | 90.9% | 0 |
| July 2025 | 21 | 21 | 85.7% | 0 |
| August 2025 | 24 | 24 | 95.8% | 0 |
| September 2025 | 21 | 21 | 90.5% | 0 |
| October 2025 | 22 | 22 | 100.0% | 0 |
| November 2025 | 19 | 19 | 100.0% | 0 |
| December 2025 | 28 | 28 | 71.4% | 0 |
| January 2026 | 53 | 51 | 82.4% | 2 |
| February 2026 | 38 | 37 | 91.9% | 1 |
| March 2026 | 30 | 30 | 83.3% | 0 |
| April 2026 | 26 | 26 | 96.2% | 0 |
| May 2026 | 31 | 31 | 96.8% | 0 |
| June 2026 | 30 | 30 | 90.0% | 0 |
| July 2026 | 30 | 28 | 53.6% | 2 |