Atlanta (ATL) to Ontario (ONT) flights
Delta Air Lines flies nonstop from Hartsfield Jackson Atlanta International Airport to Ontario International Airport, with about 20 flights a week in July 2026. The 1,900-mile flight takes about 4h 32m gate to gate.
- Distance
- 1,900 mi · 3,058 km
- Flight time
- 4h 32m
- Airlines
- 1
- Seats filled
- 86%
Airlines flying ATL to ONT
| Airline | Flights a week | Aircraft | Passengers (12 months) | Flight time |
|---|---|---|---|---|
| Delta Air Lines | 20 | Airbus A321 | 151,879 | 4h 32m |
Airlines are the operating carrier: regional airlines such as SkyWest or Horizon often fly under a larger airline's brand.
ATL to ONT flight schedule
3 flight numbers flew this route in August 2026, 2 of them almost daily. The first usually leaves at 9:25am and the last at 8:27pm. Times are local and can change; check with the airline before you book.
| Flight | Departs | Arrives | Days flown in August 2026 | On time (12 months) |
|---|---|---|---|---|
| DL 665Delta Air Lines | 9:25am | 10:42am | 31 | 84% |
| DL 2891Delta Air Lines | 5:05pm | 6:30pm | 31 | 47% |
| DL 779Delta Air Lines | 8:27pm | 9:52pm | 17 | 70% |
Is ATL to ONT on time?
From September 2025 to August 2026, 74% of 934 flights arrived within 15 minutes of schedule and 1.7% were cancelled. Flights leaving around 8am were the most punctual (89%), those around 4pm the least (59%). Most delay time was caused by the airline (crew, maintenance, cleaning, fuelling) (44%).
| Airline | Flights | On time | Average delay | Cancelled |
|---|---|---|---|---|
| Delta Air Lines | 934 | 74% | 15 min | 1.7% |
Airlines as sold: flights operated by regional partners count under the airline on the ticket. Average delay is across all completed flights, early arrivals counted as zero.
On-time arrivals by departure time
| Scheduled departure | Flights | On time, relative | On time |
|---|---|---|---|
| 8am to 9am | 56 | 89% | |
| 9am to 10am | 285 | 84% | |
| 10am to 11am | 24 | 70% | |
| 4pm to 5pm | 85 | 59% | |
| 5pm to 6pm | 151 | 67% | |
| 6pm to 7pm | 27 | 62% | |
| 7pm to 8pm | 122 | 77% | |
| 8pm to 9pm | 138 | 71% | |
| 9pm to 10pm | 46 | 58% |
Flights by month
| Month | Flights | Flights, relative | Passengers |
|---|---|---|---|
| August 2025 | 81 | 13,291 | |
| September 2025 | 80 | 13,320 | |
| October 2025 | 87 | 13,971 | |
| November 2025 | 84 | 12,882 | |
| December 2025 | 85 | 13,942 | |
| January 2026 | 62 | 9,777 | |
| February 2026 | 56 | 8,852 | |
| March 2026 | 60 | 9,709 | |
| April 2026 | 78 | 12,864 | |
| May 2026 | 91 | 15,377 | |
| June 2026 | 78 | 13,289 | |
| July 2026 | 87 | 14,919 |
Related
Source: US Department of Transportation, T-100 Segment data, August 2025 to July 2026.