Emerging adulthood is characterized by a prolonged transition from adolescence into adult roles and responsibilities. During this time, changes across multiple life domains can elicit stress, and while the impact of this has received substantial attention, measurement across different domains has been inconsistent. The ability to assess both the global stress experience and specific stressor domains (such as in family, peer and romantic relationships, study, work, finances, competing priorities and the future) would be valuable in understanding and addressing the impact of stress on well-being during this period. Informed by the Adolescent Stress Questionnaire, this study sought to design and evaluate the psychometric properties of a multidimensional self-report stress scale for use in emerging adults. The factor structure and validity of the self-report instrument was examined in two large community samples of emerging adults (Nsample1 = 760, Nsample2 = 546) aged 18 to 25 years. A series of exploratory factor analyses yielded eight internally reliable dimensions of emerging adult stress which were then validated with confirmatory factor analysis against univariate and hierarchical models. The derived scale scores related positively to established measures of general stress, anxiety and depression, and negatively to self-esteem, supporting their validity as measures of emerging adult stress. Associations across the domains with age and gender are also reported. The resultant 39-item Emerging Adult Stress Inventory offers a multidimensional self-report stress measure for emerging adults which enables investigation of specificity in the relationship between stress and well-being.