This paper explores the role of types and the intensity of transnational ties for migrants' well-being from a global perspective. Based on a literature review, two competing hypotheses are formulated-transnational resources versus transnational stress-according to which transnational ties have either a positive or a negative effect on migrants' well-being. Drawing on data from a large-scale survey of Peruvian migrants worldwide, this paper examines the strength and direction of the relationship between Peruvian migrants' transnational ties and poor well-being, the latter measured as depression/loneliness as a principal concern. While the multivariate regression results do not support the transnational resources hypothesis, partial support is found for the transnational stress hypothesis: more intense transnational ties are positively associated with poor well-being. Our study points the importance of considering transnational ties in research on migrants' well-being and indicates the relevance of developing adequate measurements and longitudinal research designs to explore the causal relationships between migrants' well-being and transnational ties.