Objective Although psychological factors have been explored in relation to other life transitions, their influence on retirement adjustment quality has been largely overlooked. This study assessed the contribution of personality traits and generativity before retirement in the prediction of hedonic and eudaimonic well‐being at two temporal points after retirement. Method This article analyzes data from the Midlife in the United States (MIDUS) longitudinal sample. Specifically, it uses a subsample of people who were not retired at Time 1, but were 9 years after at Time 2 (n = 548) and 18 years after at Time 3 (n = 351). Results After controlling both for initial values on hedonic and eudaimonic well‐being and for the effects of personal attributes and resources, higher scores on Extraversion at Time 1 significantly predicted hedonic well‐being at Time 2, whereas lower scores on Neuroticism and higher scores on generativity at Time 1 significantly predicted eudaimonic well‐being at Time 2. Neuroticism and generative concern at Time 1 remained significant in the prediction of eudaimonic well‐being at Time 3. Conclusions The study shows that personality traits and generative concern at midlife explain a meaningful part of the variation in individuals' quality of subsequent retirement adjustment.