Which departure time was most reliable for SFO to ONT?
Among qualifying SFO-to-ONT departure window results, Evening had the highest on-time rate: 92.9% of 56 flights. Night was lowest at 65.0% across 414 flights.
| Departure window | Flights | On time | 30+ min | Cancelled |
|---|---|---|---|---|
| Early morning | 83 | 85.5% | 7.2% | 0.0% |
| Late morning | 377 | 79.6% | 7.4% | 0.5% |
| Afternoon | 361 | 80.3% | 13.0% | 0.8% |
| Evening | 56 | 92.9% | 3.6% | 0.0% |
| Night | 414 | 65.0% | 23.9% | 1.7% |
Which weekday was most reliable for SFO to ONT?
Among qualifying SFO-to-ONT weekday results, Tuesday had the highest on-time rate: 83.1% of 160 flights. Friday was lowest at 71.0% across 207 flights.
| Day | Flights | On time | 30+ min | Cancelled |
|---|---|---|---|---|
| Monday | 209 | 73.2% | 17.2% | 0.5% |
| Tuesday | 160 | 83.1% | 6.9% | 0.0% |
| Wednesday | 156 | 79.5% | 14.7% | 0.0% |
| Thursday | 186 | 72.0% | 15.6% | 1.6% |
| Friday | 207 | 71.0% | 16.4% | 1.0% |
| Saturday | 164 | 81.1% | 9.8% | 0.6% |
| Sunday | 209 | 75.6% | 15.8% | 2.4% |
Which airline was most reliable for SFO to ONT?
Among qualifying SFO-to-ONT airline results, United Airlines had the highest on-time rate: 80.8% of 1,008 flights. Frontier Airlines was lowest at 54.8% across 177 flights.
| Airline | Flights | On time | 30+ min | Cancelled |
|---|---|---|---|---|
| United Airlines | 1,008 | 80.8% | 11.2% | 0.3% |
| Frontier Airlines | 177 | 54.8% | 29.9% | 3.4% |
| SkyWest Airlines | 106 | 67.0% | 15.1% | 2.8% |
Which month was most reliable for SFO to ONT?
Among qualifying SFO-to-ONT month results, March 2026 had the highest on-time rate: 89.4% of 104 flights. November 2025 was lowest at 66.7% across 105 flights.
| Month | Flights | On time | 30+ min | Cancelled |
|---|---|---|---|---|
| July 2025 | 104 | 71.2% | 25.0% | 0.0% |
| August 2025 | 109 | 75.2% | 18.3% | 0.9% |
| September 2025 | 108 | 76.9% | 13.9% | 0.0% |
| October 2025 | 114 | 73.7% | 16.7% | 0.0% |
| November 2025 | 105 | 66.7% | 20.0% | 1.9% |
| December 2025 | 104 | 72.1% | 17.3% | 1.9% |
| January 2026 | 93 | 79.6% | 10.8% | 3.2% |
| February 2026 | 79 | 77.2% | 17.7% | 0.0% |
| March 2026 | 104 | 89.4% | 2.9% | 1.0% |
| April 2026 | 124 | 83.1% | 10.5% | 0.0% |
| May 2026 | 127 | 77.2% | 7.1% | 1.6% |
| June 2026 | 120 | 70.8% | 11.7% | 0.8% |
What drove SFO to ONT delay minutes?
Late aircraft was the largest recorded SFO-to-ONT delay category, accounting for 54.7% of 20,927 BTS-attributed delay minutes during July 2025–June 2026.
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