Do social media affect users’ mental health and well-being? By now, considerable research has addressed this highly contested question. Prior studies have investigated the effects of social media use on hedonic well-being (e.g., affect and life satisfaction), psychopathology (e.g., depressive or anxiety symptoms), or psychosocial risk/resilience factors (e.g., loneliness, stress, self-esteem). Yet, public concern over social media effects often centers on more long-term negative outcomes, which may be better captured by indicators of eudaimonic well-being. Indeed, neglecting the eudaimonic side of well-being may have introduced outcome omission bias, since eudaimonia is both conceptually and empirically distinct from other dimensions of mental health and may be uniquely affected by social media use. Specifically, psychology currently theorizes eudaimonic well-being to be best represented by the experiences of (a) meaningfulness, (b) authenticity, and (c) self-actualization. A research synthesis of how social media use relates to these core indicators of eudaimonia is currently missing, however. We thus present a first narrative review that synthesizes both theoretical and empirical links between three key social media uses (i.e., active, passive, and “screen time”) and eudaimonic well-being. The synthesis shows that while there are indeed several plausible theoretical links, the evidence is too scarce and inconsistent to allow definitive conclusions at this time. We instead give recommendations for how the field can close important gaps by investigating whether social media afford or constrain opportunities to find meaning, live authentically, and grow as a person.