We examined whether age differences in life stories and personality traits mediated age differences in subjective well-being. One hundred one young, 77 middle-aged, and 81 older participants completed measures of subjective well-being and personality traits. They described chapters and specific memories in their life stories and rated these on emotional tone and positive and negative self-event connections. Older participants scored higher on subjective well-being, rated their life stories as more positive, and scored lower on neuroticism compared with both young and middle-aged participants. Age differences in subjective well-being were mediated by life stories and neuroticism, with neuroticism being the strongest mediator. We suggest that changes in personality may enable older individuals to interpret events and themselves in a positive light, which help enhance their subjective well-being.