Many perceptual abilities differ between the sexes. Because these sex differences have been documented almost exclusively in adults, they have been attributed to sex‐specific neural circuitry that emerges during development and is maintained in the mature perceptual system. To investigate whether behavioral sex differences in perception can also have other origins, we compared performance between males and females ranging in age from 8 to 30 years on auditory temporal‐interval discrimination and tone‐in‐noise detection tasks on which there are no sex differences in adults. If sex differences in perception arise only from the establishment and subsequent maintenance of sex‐specific neural circuitry, there should be no sex differences during development on these tasks. In contrast, sex differences emerged in adolescence but resolved by adulthood on two of the six conditions, with signs of a similar pattern on a third condition. In each case, males reached mature performance earlier than females, resulting in a sex difference in the interim. These results suggest that sex differences in perception may arise from differences in the maturational timing of common circuitry used by both sexes. They also imply that sex differences in perceptual abilities may be more prevalent than previously thought based on adult data alone. Transient sex differences were present during adolescence, but not before or after, on two out of six auditory perceptual conditions, with some indication of a similar outcome on a third condition. These sex differences were the result of earlier maturation in males. The presence of developmentally transient sex differences implies that sex differences in perception might be more prevalent than previously thought.