In this study we examined whether differences in the habitual use of mindfulness skills were associated with specific well-being and neuroticism aspects. Two hundred eleven volunteers aged 21-84 years completed measures of mindfulness, neuroticism, psychological well-being (PWB), and subjective well-being (SWB). Describing, observing, and acting with awareness (i.e., the mindfulness "what" skills) were positively correlated with personal growth, purpose in life, and autonomy (i.e., the "core" eudaimonic components of PWB). Nonreactivity and nonjudging (i.e., the mindfulness "how" skills) were negatively associated with neuroticism aspects, such as withdrawal (e.g., depression) and volatility (e.g., anger). Describing and nonreactivity were the only mindfulness skills significantly correlated with the SWB measures. Acting with awareness mediated the effect of both withdrawal and volatility on eudaimonic well-being outcomes. Describing had consistent mediation effects across all well-being measures, but only for the withdrawal aspect. Nonreactivity and nonjudging did not mediated withdrawal when considering eudaimonic well-being as outcomes. Mediation effects for nonjudging and nonreactivity were found between volatility and SWB markers as well as between volatility and self-acceptance, environmental mastery, and positive relations with others (i.e., the "other" eudaimonic PWB components). In sum, the mindfulness "what" skills were important for eudaimonic well-being, especially for internalizing individuals. Authors discuss the usefulness of a facet-level analysis of mindfulness for examining incremental validity of some facets over others in accounting for different well-being outcomes measures. Clinical implications are also discussed.