Best Time to Fly LAS to ONT: On-Time Stats by Hour & Airline
Harry Reid International → Ontario International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 75.8% of Las Vegas (LAS) to Ontario (ONT) flights arrived on time (2,476 scheduled flights). That is 1.8 points below the national average of 77.6%.
Among 2 airlines, Frontier Airlines led with 81.5% on time and Southwest Airlines was last with 73.5%.
Over 24 months, Tuesday was the most reliable day (86% on time) and June the worst month (70%).
The cancellation rate was 0.7% (US average 1.8%).
LAS 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 |
|---|---|---|---|---|
| Frontier Airlines | 81.5% | 75 min | 1.0% | 727 |
| Southwest Airlines | 73.5% | 48 min | 0.6% | 1,749 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly LAS to ONT
On-time arrival % by scheduled departure hour (local time), 5,182 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 6am–7am | 94.9% | 0.6% | 316 |
| 7am–8am | 93.6% | 0.7% | 442 |
| 8am–9am | 93.4% | 1.9% | 307 |
| 9am–10am | 88.5% | 1.0% | 306 |
| 10am–11am | 84.6% | 0.4% | 273 |
| 11am–12pm | 81.0% | 0.0% | 333 |
| 12pm–1pm | 79.6% | 0.3% | 305 |
| 1pm–2pm | 81.7% | 0.0% | 268 |
| 2pm–3pm | 76.6% | 0.5% | 387 |
| 3pm–4pm | 73.4% | 0.0% | 173 |
| 4pm–5pm | 70.2% | 0.4% | 266 |
| 5pm–6pm | 71.0% | 0.0% | 217 |
| 6pm–7pm | 70.0% | 0.0% | 243 |
| 7pm–8pm | 74.4% | 1.4% | 440 |
| 8pm–9pm | 71.1% | 1.1% | 374 |
| 9pm–10pm | 68.6% | 0.0% | 236 |
| 10pm–11pm | 53.7% | 0.7% | 287 |
| 11pm–12am | Limited data | 9 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on LAS 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) | 80.9% | +0.3 pts | 0.0% | 89 |
| Christmas & New Year (Dec 20 - Jan 3) | 70.4% | -10.2 pts | 1.0% | 208 |
| Summer peak (Jun 15 - Aug 15) | 72.0% | -8.6 pts | 0.8% | 864 |
| All other days | 80.6% | — | 0.6% | 4,021 |
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).