Is Flying Getting More or Less Reliable Over Time?

Slightly less reliable, over the most recent year measured. Comparing the two most recent 12-month windows in FlightRecord's data, 77.1% of US flights arrived on time between June 2025 and May 2026, down from 79.3% between June 2024 and May 2025 — a real, if modest, year-over-year decline of about 2.2 percentage points.

• On-time performance fell from 79.3% to 77.1% year over year, comparing the two most recent 12-month windows (June 2024–May 2025 vs. June 2025–May 2026), each covering more than 7 million flights.
• Fall and early winter drove most of the decline — October, November, and December 2025 each ran several points worse than the same month a year earlier; October alone fell from 86.7% on time to 79.5%.
• Not every month got worse — July, August, February, and May each posted a slightly better on-time rate in their most recent occurrence than the year before.
• July 2024 was the least reliable single month in the full 24-month dataset, at 70.1% on time — barely worse than July 2025's 70.7%, underscoring that summer is consistently the toughest season to fly. See the worst month to fly for more.
• October 2024 was the most reliable single month in the dataset, at 86.7% on time.

Comparing the two most recent 12-month windows

To measure a real trend rather than one unusually good or bad month, this comparison uses two full 12-month windows: June 2024 through May 2025 (7,063,975 flights, 79.3% on time) versus June 2025 through May 2026 (7,047,314 flights, 77.1% on time). Both windows cover a comparable volume of flights and a full annual cycle of seasons, so the 2.2-point gap between them reflects a genuine shift rather than a difference in which months happened to be included.

Month-by-month: how each month changed year over year

On-time rate for each calendar month, comparing its two most recent occurrences:

• June — 74.8% → 71.4% (down 3.4 points)
• July — 70.1% → 70.7% (up 0.6 points)
• August — 76.3% → 77.2% (up 0.9 points)
• September — 84.4% → 83.2% (down 1.2 points)
• October — 86.7% → 79.5% (down 7.2 points, the largest drop)
• November — 85.2% → 79.3% (down 5.9 points)
• December — 78.6% → 73.0% (down 5.6 points)
• January — 81.0% → 79.0% (down 2.0 points)
• February — 79.0% → 80.0% (up 1.0 point)
• March — 80.2% → 75.4% (down 4.8 points)
• April — 80.1% → 79.6% (down 0.5 points)
• May — 76.2% → 78.4% (up 2.2 points)

Is this a real trend, or just normal variation?

Two years of data — one full comparison — isn't enough to call this a permanent trend, and it's worth being direct about that limit. What the data does show clearly is that fall 2025 was meaningfully worse than fall 2024 across three consecutive months (October, November, December), which is a large enough and consistent enough shift to be a real pattern rather than noise from a single bad week. Whether that pattern continues, reverses, or was itself a one-off will only be visible with more months of data — this comparison will keep updating as new months are added; check the monthly reports for the latest figures.

What this means for travelers

Even in the more recent, slightly worse year, roughly 3 out of 4 flights still arrived on time. A 2.2-point national shift is real but small next to the differences between individual airlines, airports, and routes — the gap between the most and least reliable major airline alone is about 12 points. If you're planning a specific trip, checking that route's, airport's, or airline's own page will tell you far more than the national trend will.

For the same trend broken down by individual airport, see which US airports improved their on-time performance the most.

Frequently asked questions

What was the most reliable month in this data?

October 2024, at 86.7% on time — the best of the 24 months measured.

What was the least reliable month in this data?

July 2024, at 70.1% on time, just ahead of July 2025's 70.7% — the two worst months on record, both in the same calendar month a year apart.

Why did fall 2025 get so much worse than fall 2024?

The BTS on-time data shows the size of the drop clearly but doesn't itself isolate a single national cause — a national monthly shift like this can come from weather, air traffic control capacity, or a mix of factors that varies by region. For a specific route, airport, or airline you fly, check that page's own delay-cause breakdown for a more direct answer.

How often is this comparison updated?

Monthly, alongside the rest of the site's data — BTS publishes with roughly a two-month lag. See the monthly reports for the latest national trend, or the methodology for how the data is sourced and refreshed.