Flight profile · Delta Air Lines
DL1223
Atlanta (ATL) to Houston (IAH) · scheduled 4:25 PM – 5:38 PM
How DL1223 performs
716 operations, 2023-09-05 to 2026-06-26.
DL1223 arrived on time 74.3% of the time, against 75.7% for all ATL → IAH flights — this specific departure is 1.4 percentage points worse than the route as a whole. Against Delta Air Lines’s own flights on this route it is 2.3 points worse.
Source: US DOT Bureau of Transportation Statistics · 716 operations between 2023-09-05 to 2026-06-26
Against the rest of the route
| On time | Cancelled | Median delay | Severe | Flights | |
|---|---|---|---|---|---|
| DL1223 | 74.3% | 1.12% | 0 min | 7.5% | 716 |
| Delta Air Lines on ATL → IAH | 76.6% | 1.49% | -2 min | 7.0% | 7,119 |
| All ATL → IAH flights | 75.7% | 1.65% | -3 min | 8.7% | 13,939 |
Source: FlyerIntel analysis of US DOT BTS data · 2023-09-05 to 2026-06-26
Other routes DL1223 has flown
A flight number is a slot in a schedule, and carriers reassign it. These are the other city pairs this number served in the analysis period.
| Route | Operated | Flights | On time |
|---|---|---|---|
| IAH→ATL Houston to Atlanta | 2023-09-10 – 2026-06-26 | 653 | 76.9% |
| SEA→GEG Seattle to Spokane | 2026-03-08 – 2026-04-12 | 36 | — |
| RSW→BOS Fort Myers to Boston | 2025-06-08 – 2025-12-19 | 195 | 79.9% |
| PSP→MSP Palm Springs to Minneapolis | 2023-12-22 – 2024-01-07 | 17 | — |
| ATL→BTR Atlanta to Baton Rouge | 2023-11-02 – 2023-11-03 | 2 | — |
| BTR→ATL Baton Rouge to Atlanta | 2023-11-02 – 2023-11-03 | 2 | — |
| LGA→IAH New York to Houston | 2023-07-15 – 2023-09-04 | 10 | — |
| RDU→LAX Raleigh–Durham to Los Angeles | 2023-07-10 – 2023-07-31 | 13 | — |
| BDL→MSP Hartford to Minneapolis | 2023-07-01 – 2023-07-08 | 7 | — |
| MSP→BDL Minneapolis to Hartford | 2023-07-01 – 2023-07-08 | 7 | — |
Because the same number has served different journeys, the statistics above describe only the route DL1223 currently operates. Blending them would produce an average of two different flights.
Data and methodology
Calculated by FlyerIntel from 716 records of DL1223 operating ATL → IAH, published by the US DOT Bureau of Transportation Statistics. A flight counts as delayed when it arrives 15 or more minutes after schedule. Cancelled and diverted flights are excluded from the on-time rate and reported separately. Flight numbers are resolved as carrier plus number plus route, because the same number serves different routes over time.