The vast majority of flights in the United States — about three out of four — are less than half full, according to Airlines for America, an industry organization.

In 2026, planes are "fuller" than at almost any point in aviation history, with a global passenger load factor averaging between 83% and 85%. In many major markets like the U.S. and Europe, this number often hits 90% or higher on peak travel days. This is because airlines in 2026 use sophisticated AI-driven "revenue management" systems that optimize flight schedules to ensure very few seats go unsold. Additionally, persistent "supply-side" constraints—including delays in new aircraft deliveries from Boeing and Airbus—mean that there is more demand for travel than there is available plane capacity. While travelers might occasionally find a half-empty flight on a "dead-head" route or at 4:00 AM on a Tuesday, the "empty middle seat" has become a rare luxury. For passengers, this means fuller overhead bins, longer boarding times, and a higher likelihood of being asked to gate-check carry-on bags as flights consistently operate at or near their maximum certified capacity.