Holiday travel
July 4 at IAD
Washington Dulles International Airport, Washington, VA. July 2023 – July 2026. Set against IAD’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 worse in one of the four years. The gap ran from 3.7 points below usual in 2023 to 11.8 points above usual in 2024.
2.19% of scheduled departures were cancelled across the July 4 windows, against 2.01% on ordinary days of the same weekdays. It was lower in one of the four years and higher in one.
| Year | Departures | On time | Usual | Gap, points | Cancelled | Usual |
|---|---|---|---|---|---|---|
| 2023Jul 1–5, 2023 | 664 | 69.6% | 73.3% | −3.7worse | 1.66% | 1.99% |
| 2024Jul 1–5, 2024 | 737 | 84.0% | 72.2% | +11.8better | 0.54% | 1.93% |
| 2025Jul 1–5, 2025 | 797 | 75.5% | 72.2% | +3.3better | 3.51% | 2.01% |
| 2026Jul 1–5, 2026 | 810 | 74.9% | 71.1% | +3.8better | 2.84% | 2.10% |
| All years4 windows | 3,008 | 76.2% | 72.2% | +4.0better | 2.19% | 2.01% |
Day by day
July 1 (Sat, Mon, Tue, Wed) was the worst day of the window in three of the four years. Over the years it ran 67.9% on time, 6.1 points below what ordinary days of the same weekdays had.
July 4 was the best day of the window in two of the four years. Over the years it ran 77.0% on time, 5.2 points above what ordinary days of the same weekdays had.
July 4 itself carried 14% fewer departures than an ordinary day of the same weekday and ran 77.0% 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 40%, 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 | 75.4% | 70.7% | +4.7better | 1.67% | — · 82.0 · 67.6 · 76.3 |
| Jun 29Sat, Sun, Mon · outside the window | about the same | 76.6% | 72.5% | +4.1better | 1.03% | — · 75.2 · 66.5 · 87.4 |
| Jun 30Sun, Mon, Tue · outside the window | 3% fewer | 69.7% | 73.3% | −3.6about the same | 2.73% | — · 59.3 · 61.1 · 87.5 |
| Jul 1Sat, Mon, Tue, Wed | 6% fewer | 67.9% | 74.0% | −6.1worse | 3.99% | 49.2 · 78.1 · 50.0 · 88.9 |
| Jul 2Sun, Tue, Wed, Thu | 6% fewer | 83.1% | 72.5% | +10.6better | 1.15% | 74.2 · 91.3 · 75.6 · 89.4 |
| Jul 3Mon, Wed, Thu, Fri | 7% fewer | 77.4% | 71.2% | +6.2better | 1.62% | 70.3 · 89.3 · 75.3 · 74.4 |
| July 4Tue, Thu, Fri, Sat | 14% fewer | 77.0% | 71.8% | +5.2better | 1.62% | 80.0 · 75.4 · 87.8 · 64.2 |
| Jul 5Wed, Fri, Sat, Sun | 3% fewer | 75.0% | 71.3% | +3.7better | 2.56% | 73.8 · 85.7 · 87.4 · 54.4 |
| Jul 6Thu, Sat, Sun, Mon · outside the window | about the same | 72.7% | 72.1% | +0.6about the same | 2.03% | 68.0 · 88.2 · 82.1 · 53.7 |
| Jul 7Fri, Sun, Mon, Tue · outside the window | 4% fewer | 69.8% | 72.1% | −2.3about the same | 1.74% | 67.6 · 81.5 · 68.6 · 62.0 |
| Jul 8Sat, Mon, Tue, Wed · outside the window | 3% fewer | 70.9% | 74.0% | −3.1about the same | 1.78% | 65.4 · 81.1 · 52.8 · 84.0 |
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 IAD were Saturday, Jul 1, 2023 (130 departures), Wednesday, Jul 5, 2023 (149 departures), Monday, Jul 1, 2024 (149 departures), Tuesday, Jul 2, 2024 (149 departures), Wednesday, Jul 2, 2025 (162 departures), Thursday, Jul 3, 2025 (176 departures), Thursday, Jul 2, 2026 (171 departures), and Sunday, Jul 5, 2026 (177 departures).
Across the whole window, flights leaving 9 AM–12 PM had the highest on-time rate: 89.3%, 5.4 points above usual for that time of day. Those leaving 3–6 PM had the lowest: 60.6%, still 4.4 points above usual for that time of day.
The holiday helped flights leaving 6–9 PM the most (13.3 points above usual for that time of day) and those leaving 9 PM–5 AM the least (1.5 points above).
On each year’s two busiest days, flights leaving 5–9 AM had the highest on-time rate: 84.9%, still 1.3 points below usual for that time of day. Those leaving 9 PM–5 AM had the lowest: 58.1%, 8.7 points below usual for that time of day.
Against usual for their time of day, flights leaving 12–3 PM did best (+6.1 points) and those leaving 9 PM–5 AM did worst (−8.7 points).
| Leaving | On time, whole window | Usual | Gap, points | On time, busiest days | Usual | Gap, points |
|---|---|---|---|---|---|---|
| 5–9 AM | 88.1% | 85.6% | +2.5better | 84.9% | 86.2% | −1.3about the same |
| 9 AM–12 PM | 89.3% | 83.9% | +5.4better | — | — | — |
| 12–3 PM | 80.7% | 78.9% | +1.8about the same | 84.6% | 78.5% | +6.1better |
| 3–6 PM | 60.6% | 56.2% | +4.4better | 60.1% | 56.8% | +3.3about the same |
| 6–9 PM | 68.3% | 55.0% | +13.3better | — | — | — |
| 9 PM–5 AM | 68.0% | 66.5% | +1.5about the same | 58.1% | 66.8% | −8.7worse |
Cancellations
The worst day for cancellations in each year was Tuesday, Jul 1, 2025 (11.88% of that day’s departures, 68% of the window’s cancellations) and Sunday, Jul 5, 2026 (9.04% of that day’s departures, 70% of the window’s cancellations).
IAD beside every covered airport
Storms and outages move whole regions at once. This puts IAD’s year beside the year of all covered airports together, each against its own usual, to show whether IAD did better or worse than the network.
| Year | IAD on time | IAD, gap from usual | All airports on time | All airports, gap from usual |
|---|---|---|---|---|
| 2023Jul 1–5, 2023 | 69.6% | −3.7 | 73.9% | +2.9 |
| 2024Jul 1–5, 2024 | 84.0% | +11.8 | 82.2% | +11.7 |
| 2025Jul 1–5, 2025 | 75.5% | +3.3 | 73.5% | +2.3 |
| 2026Jul 1–5, 2026 | 74.9% | +3.8 | 73.1% | +3.2 |
For every holiday at once, see the five holidays at IAD, or the network view.