Meaning in life has been established as a key factor of human well-being and flourishing. Beneficence and the three psychological needs of self-determination theory-autonomy, competence, and relatedness-have all been individually studied as antecedents of meaningfulness. Yet, no previous research has examined them neither longitudinally nor simultaneously as predictors of meaning over time. In a three-wave longitudinal study in Chile (n: T1 = 1477, T2 = 820, T3 = 487) we examined the reciprocal relations between autonomy, competence, relatedness, beneficence, and meaning, using cross-lagged panel analysis. Taken individually, each of the four factors predicted meaning, and when entered simultaneously into the same model, competence, relatedness, and beneficence predicted meaning over time. Furthermore, we found that meaning predicted all four factors over time. Our results thus advance research on meaning in life by examining key predictors of it and showing that meaning itself predicts the same factors dynamically over time.