Having a sense of purpose is recognized as an important resource for maintaining health and well-being over the life span. We examined associations of individual differences in sense of purpose with levels and rates of change in indices of aging well (health, cognition, and depressive symptoms) in a sample of 1,475 older adults (Mage = 77.06 years, SD = 6.27; 50% female) assessed on up to 6 occasions over 18 years. We also conducted survival analysis to examine associations of purpose with longevity. We hypothesized that a higher sense of purpose would be associated with better performance on the aging well measures, and that those with a higher sense of purpose would show shallower declines in aging well over time. Results indicated that participants who scored higher on sense of purpose reported lower levels of functional disability, performed better on cognitive tests (episodic memory and speed of processing), and reported better self-rated health and fewer depressive symptoms. Sense of purpose was not associated with individual differences in rates of change in the aging well indices with the exception of speed of processing, for which a higher sense of purpose was associated with marginally shallower rates of decline. Higher sense of purpose was also associated with increased probability of survival, although this association became weaker over time. The findings support the notion that purposeful living contributes to health and well-being. At the same time, higher sense of purpose may not buffer against more pervasive losses in health that become more common in oldest-old adulthood.