Feeds mainly on moths and other soft-bodied insects. Also eats beetles and hard-shelled insects to some extent. Foraging flight is slow and fluttery with short glides. Uses echolocation to locate prey. Females may form nursery colonies or occur as solitary individuals in dense foliage or hollow trees.
Most activity is crepuscular.
Emerges earlier than most bats. Migrates to hibernation site. May make long migratory flights. Though the migratory paths of individual bats are unknown, it is likely that some California silver-haired bats winter in Mexico. Migration often results in occurrences in habitats or locations out of the normal range.