The goals of this study were to examine maternal beliefs about the primary benefits and costs of their children’s time spent with friends, and to explore child age and gender differences in these beliefs. Participants were N = 512 mothers (M
childage = 10.18 years; 11% ethnic minority). Open-ended responses to questions about the benefits and costs were coded and analysed, with results indicating that mothers consider opportunities for social skills and social-cognitive development a primary benefit of spending time with friends. Negative friend influence was the most commonly cited cost of friendship. Child age was associated with a number of maternal beliefs (e.g., mothers of adolescents were more likely than mothers of young children to report intimacy as a benefit), but child gender was not. Findings highlight the importance of considering child age in studies of maternal beliefs about friendship and set the stage for future research in this area.