The definitive reasons why summer is the worst time to fly in the US

Looks like summer.
Looks like summer.
Image: AP Photo/David Tulis
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Thinking about flying around the US this summer? Consider yourself warned: not only are flights, on average, at their most expensive in June, July, and August—they’re also the most likely to be utterly miserable.

Most expensive

In the past two years, airfares have hit elevated levels for tickets sold in May and June, up as much as 17.4% over when prices are lower in January, according to data collected by the US Bureau of Labor Statistics (BLS). Many of the tickets priced in May and June are for flights in July and August.

The BLS only gives us a glimpse at the industry-wide trends of ticket pricing and airline market and price their fares in much more nuanced and complex ways. Nonetheless, almost no routes are at their cheapest in summer.

Most crowded

More passengers fly into, out of, and around the US in summer than any other time of year. But the airports stay the same size.

To meet demand, airlines fly more planes on more routes during the summer, so it’d be easy to think that there would be more empty seats. In fact, it doesn’t get better once you get on the plane. They’re most crowded in summer, too. The industry’s capacity utilization is at its highest in June, July, and August.

Known as load-factor, the metric is the portion of seats on flights that were filled to the number of seats that were available weighted for the length of the flights. So, even though airlines have more seats to fill in summer, they’re better at filling them then than any other time of year.

Most delayed

To add insult to injury, summer flights are most likely to arrive late or not at all. Between delays, diversions, and cancelations, June and July have a worse on-time performance than December and January.

On-time performance varies from year to year, but 75.3% of flights in July have landed on time since 2011. By that same measure, flights in November have arrived on time 83.8% of the time.

Delays, cancelations, and diversions are caused by all sorts of events, from weather, to air traffic control issues, to sick passengers, to corporate logistics.


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