We explore the relationship between chief executive officer (CEO) personality traits and corporate social responsibility (CSR) reporting. Upper echelons theory indicates that the values, experiences, and personalities of top organizational managers influence their organization's strategic decisions and effectiveness. We utilize IBM Watson Personality Insights software to infer CEOs’ personality traits based on their responses to questions raised by analysts during year‐end conference calls; we obtain CEOs’ Big Five personality traits—openness, conscientiousness, extraversion, agreeableness, and neuroticism—from which we compute a measure of (...) their risk tolerance. Using a longitudinal dataset of Standard and Poor's 500 firms for 2008–2015, we document that high CEO risk tolerance is related to lower CSR report readability and smaller CSR disclosure volume. This finding indicates that executives who are comfortable with greater risk are more willing to supply stakeholders with reports that are shorter and require greater effort to understand. Exploration of the association between CEO Big Five personality traits and CSR report readability and disclosure volume allows key stakeholders to better comprehend CSR disclosures and connotations thereof. Overall, our results contribute to the debate on how CEO personality traits affect organizations’ CSR disclosure reporting strategies, and support upper echelons theory in the CSR setting. (shrink)