Physical traits are thought to be used as indicators of mate quality, allowing individuals to select mates most likely to help them bear the fittest offspring. As the capacity for human sexual behaviour emerges at puberty, we investigated whether adult-like judgments of the relative attractiveness of opposite-sex individuals also arise at puberty. Following previous research, we focussed on facial and vocal attractiveness, which are known to be used in human mate choice and to carry concordant information regarding mate quality. Here we show that males with more attractive faces have more attractive voices as judged by female adults and adolescents, but not by female children. This suggests that cues of facial and vocal attractiveness provide similar information, but that awareness of these cues does not develop fully until reproductive capability, when mate choice judgments become relevant. Adolescents’ judgments also mirrored those of adults in that, like adults, they preferred lower-pitched male voices, and as a group made concordant judgments about facial attractiveness. However, they did not make similarly concordant judgments about vocal attractiveness, suggesting that a further period of maturation and learning is required to fully develop optimal judgments for mate choice.