Objective As alcohol consumption generally occurs in interpersonal contexts, many studies have examined the psychosocial mechanisms underlying drinking habits. However, most have focused on young/student populations, and far less is known regarding how these psychosocial determinants evolve through adulthood. We thus compared the weight of psychosocial factors in problematic alcohol consumption among young, middle-aged and older people from the general population. Methods A general population sample completed an online survey (N = 614, Mage = 34.44, Range= 18–85). We measured demographic variables, problematic alcohol consumption and alcohol-related psychosocial factors (i.e. expectations, motives, norms, social identity, anxiety and depression). We performed dominance analyses to rank the importance of these psychological factors in explaining problematic alcohol consumption across young (18–24, n = 252), middle-aged (25–40, n = 179), and older (>40, n = 183) individuals. Results In young adults, enhancement motives were the most important determinant of problematic alcohol consumption, followed by social drinking identity, coping and social motives. In the middle-aged group, social identity had the highest contribution, followed by social and enhancement motives. Finally, problematic alcohol consumption among older adults was mainly related to coping motives and social identity. Discussion We showed that the psychosocial determinants of problematic alcohol consumption differ with age. While social drinking identity has a significant influence throughout the age groups, we documented a progressive shift from positive (social/enhancement) to negative (coping) reinforcement between younger and older individuals. This study provides a better understanding of the profiles of consumers according to age, and offers guidelines to adapt prevention and interventions to the age group targeted.