Personality traits vary both between and within people. This study examines the daily within- and between-person variability of positively valued lower-order personality traits, namely character strengths, their convergence with trait character strengths, and their relationships to daily measures of affect. German-speaking participants (N = 172, 84.2% women; mean age = 25.5 years) participated in a two-week daily diary study. They completed a measure of character strength traits at baseline and daily measures of character strength states and positive and negative affect. Results suggested that character strength traits converged well with aggregated states. Overall, we found high within-person variability in most character strengths. Within-person associations with affect were widely parallel to previously reported between-person associations. Also, these associations were widely independent of trait levels of character strengths for most strengths. Thus, for instance, behaving more gratefully than usual is as beneficial to the habitually grateful as to the ungrateful. Finally, within-person variability in character strengths goes along with higher scores in trait levels of perspective and other strengths and might be considered adaptive. Our findings inform further research on the whole-trait theory and character-strengths-based interventions.