Holiday travel
July 4 at ONT
Ontario International Airport, Ontario, CA. July 2023 – July 2026. Set against ONT’s own ordinary days of the same weekday in the weeks around each holiday.
The window, year by year
The window runs July 1 through July 5, around July 4, whatever weekday it falls on. In the data: Jul 1–5, 2023; Jul 1–5, 2024; Jul 1–5, 2025; Jul 1–5, 2026. July 4 fell on a Tuesday in 2023, Thursday in 2024, Friday in 2025, and Saturday in 2026. Four windows are in the data: enough to see whether a day repeats, not enough to call it a rule.
Compared with ordinary days, July 4 flights were better in three and about the same in one of the four years. The gap ran from 1.3 points below usual in 2025 to 8.4 points above usual in 2024.
0.57% of scheduled departures were cancelled across the July 4 windows, against 1.24% on ordinary days of the same weekdays. It was lower in two of the four years.
| Year | Departures | On time | Usual | Gap, points | Cancelled | Usual |
|---|---|---|---|---|---|---|
| 2023Jul 1–5, 2023 | 323 | 84.7% | 79.1% | +5.6better | 0.62% | 1.24% |
| 2024Jul 1–5, 2024 | 361 | 86.9% | 78.5% | +8.4better | 0.00% | 1.18% |
| 2025Jul 1–5, 2025 | 352 | 78.3% | 79.6% | −1.3about the same | 0.28% | 1.12% |
| 2026Jul 1–5, 2026 | 365 | 84.7% | 78.7% | +6.0better | 1.37% | 1.43% |
| All years4 windows | 1,401 | 83.7% | 78.9% | +4.8better | 0.57% | 1.24% |
Day by day
No single day has enough flights in one year to compare the years, so the days are ranked on all four years pooled: July 1 ran lowest (80.1% on time, about level with usual) and July 4 highest (94.5%, 14.4 points above usual). This cannot say whether the same day was worst or best in each year.
July 4 itself carried 21% fewer departures than an ordinary day of the same weekday and ran 94.5% on time.
- Better than usual
- Worse than usual
- About the same
- What ordinary days of the same weekday had
- Lowest to highest single year
- Lighter bars: days just outside the window
Bars show the on-time arrival rate and start at 70%, not zero.
| Day | Departures against an ordinary day | On time | Usual | Gap, points | Cancelled | Each year: 2023, 2024, 2025, 2026 |
|---|---|---|---|---|---|---|
| Jun 28Fri, Sat, Sun · outside the window | about the same | 83.1% | 79.3% | +3.8about the same | 1.79% | — · — · — · — |
| Jun 29Sat, Sun, Mon · outside the window | about the same | 86.0% | 79.0% | +7.0better | 1.33% | — · — · — · — |
| Jun 30Sun, Mon, Tue · outside the window | about the same | 84.1% | 78.2% | +5.9better | 1.69% | — · — · — · — |
| Jul 1Sat, Mon, Tue, Wed | 3% fewer | 80.1% | 79.5% | +0.6about the same | 0.69% | — · — · — · — |
| Jul 2Sun, Tue, Wed, Thu | 7% fewer | 80.1% | 78.4% | +1.7about the same | 0.35% | — · — · — · — |
| Jul 3Mon, Wed, Thu, Fri | 5% fewer | 85.2% | 78.1% | +7.1better | 0.00% | — · — · — · — |
| July 4Tue, Thu, Fri, Sat | 21% fewer | 94.5% | 80.1% | +14.4better | 1.67% | — · — · — · — |
| Jul 5Wed, Fri, Sat, Sun | 6% fewer | 80.2% | 78.9% | +1.3about the same | 0.36% | — · — · — · — |
| Jul 6Thu, Sat, Sun, Mon · outside the window | 2% more | 80.4% | 78.8% | +1.6about the same | 1.31% | — · — · — · — |
| Jul 7Fri, Sun, Mon, Tue · outside the window | 2% more | 74.4% | 78.3% | −3.9about the same | 0.94% | — · — · — · — |
| Jul 8Sat, Mon, Tue, Wed · outside the window | about the same | 82.0% | 79.4% | +2.6about the same | 2.97% | — · — · — · — |
A dash means fewer than 120 flights stood behind the figure, or behind the ordinary days it would be compared with: too few to print a rate, and nothing is estimated in its place. “Usual” is what ordinary days of the same weekday had at the same place in the weeks around the holiday, weighted by the flights being compared.
Which departure times held up
The busiest days at ONT were Monday, Jul 3, 2023 (67 departures), Wednesday, Jul 5, 2023 (74 departures), Monday, Jul 1, 2024 (78 departures), Wednesday, Jul 3, 2024 (79 departures), Tuesday, Jul 1, 2025 (77 departures), Thursday, Jul 3, 2025 (80 departures), Thursday, Jul 2, 2026 (79 departures), and Friday, Jul 3, 2026 (78 departures).
Across the whole window, flights leaving 5–9 AM had the highest on-time rate: 92.6%, 2.2 points above usual for that time of day. Those leaving 3–6 PM had the lowest: 75.4%, still 3.3 points above usual for that time of day.
The holiday helped flights leaving 6–9 PM the most (7.9 points above usual for that time of day) and those leaving 5–9 AM the least (2.2 points above).
| Leaving | On time, whole window | Usual | Gap, points | On time, busiest days | Usual | Gap, points |
|---|---|---|---|---|---|---|
| 5–9 AM | 92.6% | 90.4% | +2.2about the same | 92.1% | 89.8% | +2.3about the same |
| 9 AM–12 PM | 88.5% | 84.2% | +4.3about the same | — | — | — |
| 12–3 PM | 77.4% | 72.4% | +5.0about the same | — | — | — |
| 3–6 PM | 75.4% | 72.1% | +3.3about the same | — | — | — |
| 6–9 PM | 75.9% | 68.0% | +7.9better | — | — | — |
| 9 PM–5 AM | 78.9% | 72.3% | +6.6about the same | — | — | — |
ONT beside every covered airport
Storms and outages move whole regions at once. This puts ONT’s year beside the year of all covered airports together, each against its own usual, to show whether ONT did better or worse than the network.
| Year | ONT on time | ONT, gap from usual | All airports on time | All airports, gap from usual |
|---|---|---|---|---|
| 2023Jul 1–5, 2023 | 84.7% | +5.6 | 73.9% | +2.9 |
| 2024Jul 1–5, 2024 | 86.9% | +8.4 | 82.2% | +11.7 |
| 2025Jul 1–5, 2025 | 78.3% | −1.3 | 73.5% | +2.3 |
| 2026Jul 1–5, 2026 | 84.7% | +6.0 | 73.1% | +3.2 |
For every holiday at once, see the five holidays at ONT, or the network view.