The majority of adults feel considerably younger than their chronological age. Numerous studies suggest that maintaining a younger subjective age is linked to greater life satisfaction. However, whether there is a limit beyond which feeling younger becomes detrimental is not well understood. Here, we use response surface analysis to examine the relationships between subjective age, chronological age, and life satisfaction in in a large sample spanning adulthood (N = 7,356; 36-89 years). We find that there is a limit to feeling younger: People who feel younger by a certain amount, but not more, have the highest levels of life satisfaction. In addition, our findings suggest that the discrepancy between subjective and chronological age at which life satisfaction is highest increases across the adult age span. Taken together, these findings reveal that beyond a certain point, feeling younger than one's chronological age may be psychologically harmful. (PsycInfo Database Record (c) 2021 APA, all rights reserved).