Life satisfaction is universally important and a pinnacle of human pursuits. Uncontrollable factors, such as personality, influence life satisfaction. Interventions, such as volunteering, also impact life satisfaction. Previous studies have provided evidence that personality traits affect life satisfaction, that volunteerism impacts life satisfaction, and that personality traits influence volunteerism. After synthesizing these prior results, I employed methods from structural equation modeling (SEM) to explore the partial mediation of volunteerism on the effects of the Big Five personality traits on life satisfaction. Contrary to the hypothesis, the SEM did not fit the observed data well. However, the analyses were limited by highly skewed distributions of item responses. Nonetheless, there was not sufficient statistical evidence to support the claim that frequency of volunteering partially mediates the effects of the Big Five personality traits on current life satisfaction.