Optimistic assessments of life chances can positively influence life outcomes, but conflicting theories suggest these assessments either reflect structural privilege or develop as a result of childhood hardship. In addition, competing hypotheses suggest that these assessments may matter differently depending on who holds them. We examine whether family socioeconomic status shapes adolescents’ expectations about how successful their lives will turn out. We distinguish generalized life expectations (GLE), capturing anticipated success in life across multiple domains, from intergenerational comparative expectations (ICE), which register expectations about improvement relative to observed success within the respondent’s family lineage. We find that adolescents from higher socioeconomic status families are simultaneously more optimistic about their likely success in life (GLE) but less likely to anticipate relative improvement in life success across generations (ICE). Holding high GLE in combination with low ICE predicted doing better in adulthood across a range of health, attainment, and well-being outcomes, though in most cases high GLE, regardless of ICE, was the key. These beneficial patterns are, for the most part, at least as beneficial for socioeconomically disadvantaged youth as they are for advantaged youth.