Bovista pila, commonly known as the tumbling puffball, is a species of puffball fungus in the family Agaricaceae. A temperate species, it is widely distributed in North America, where it grows on the ground on road sides, in pastures, grassy areas, and open woods. There are few well-documented occurrences of B. pila outside North America. B. pila closely resembles the European B. nigrescens, from which it can be reliably distinguished only by microscopic characteristics.