The passage of time is fundamentally experienced through people's interaction with their social worlds. Life-course scholars acknowledge the multiple aspects of time-based experience but have given little attention to age identity in a dynamic context. Drawing from a stress-process model, we expected that turbulence within people's family relations and health declines would produce increases in subjective age. Family role transitions were also examined as potential factors that would hasten subjective aging, but only to the extent that they produced stress. We used the Midlife Development in the United States study, a nationally representative longitudinal survey. Regression results show that turbulence within one's family accelerated age identity and that the effect of diminishing psychosocial resources explained this relationship. For the most part, however, changes within family roles did not affect age identity. On the other hand, the incidence of chronic health problems increased subjective ages, and this relationship too was mediated by the depletion of psychosocial resources. The findings demonstrate an interconnection between the stress process and age identity. Broadening our conception of time-based experience with attention to the stress process offers exciting directions for future theory and research in life course sociology. (Contains 3 tables and 7 footnotes.)