Best Time to Fly HOU to ONT: On-Time Stats by Hour & Airline
William P Hobby → Ontario International
Data through July 2026 · Last updated October 18, 2026
362 flights were scheduled from Houston (HOU) to Ontario (ONT) in the last 12 months, and 78.0% of those that flew arrived on time, in line with the US average of 77.6%.
Southwest Airlines was the only reporting airline with regular flights on this route.
Over 24 months, Thursday was the most reliable day (87% on time) and June the worst month (67%).
The cancellation rate was 0.3% (US average 1.8%).
HOU to ONT on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| Southwest Airlines | 78.0% | 57 min | 0.3% | 362 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly HOU to ONT
On-time arrival % by scheduled departure hour (local time), 725 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 7am–8am | 87.3% | 0.0% | 56 |
| 8am–9am | 89.4% | 0.0% | 208 |
| 9am–10am | 92.3% | 2.5% | 80 |
| 10am–11am | Limited data | 16 | |
| 11am–12pm | Limited data | 28 | |
| 12pm–1pm | Limited data | 16 | |
| 1pm–2pm | 69.4% | 0.0% | 85 |
| 2pm–3pm | 80.8% | 0.0% | 52 |
| 3pm–4pm | 82.0% | 0.0% | 39 |
| 4pm–5pm | Limited data | 19 | |
| 5pm–6pm | Limited data | 24 | |
| 6pm–7pm | Limited data | 20 | |
| 7pm–8pm | Limited data | 12 | |
| 8pm–9pm | Limited data | 15 | |
| 9pm–10pm | 63.3% | 2.0% | 50 |
| 10pm–11pm | Limited data | 5 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on HOU to ONT
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | Limited data | 12 | ||
| Christmas & New Year (Dec 20 - Jan 3) | 76.7% | -7.3 pts | 0.0% | 30 |
| Summer peak (Jun 15 - Aug 15) | 79.0% | -4.9 pts | 0.0% | 124 |
| All other days | 83.9% | — | 0.5% | 559 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).