Following theoretical models on wishful thinking, we investigated (a) whether personal aging ideals are discordant from self-perceptions of aging, (b) how such aging discordances evolve across adulthood, (c) whether current aging discordances are related to anticipated future aging discordances, and (d) whether aging discordances are related to a lower psychological well-being. We captured subjective age discordance (SAD) as the discrepancy between current perceived age and ideal age, and we captured subjective life-expectancy discordance (SLED) as the discrepancy between perceived life expectancy and ideal life expectancy. For the analyses, we used cross-sectional data from 1,015 individuals (M = 40.0 years, SD = 17.9 years; 52.1% women) and 2-year longitudinal data from 258 individuals (M = 55.3 years, SD = 17.3 years; 70.5% women). Both aging discordances were clearly present across the adult life span; that is, ideal ages were lower than perceived ages, and ideal life expectancies were higher than perceived life expectancies. A stronger SLED was associated with a stronger SAD, both cross-sectionally and longitudinally. Both discordances were also associated with lower psychological well-being in the cross-sectional analyses. Over time, lower life satisfaction predicted increases in SAD, and SLED predicted increases in negative affect. The results indicate that SAD and SLED are both highly prevalent and potentially functional because they seem to be related to psychological well-being. The discussion focuses on SAD and SLED as constructs for future research, their antecedents, and potential consequences. (PsycInfo Database Record (c) 2020 APA, all rights reserved).