Phishing research presents conflicting findings regarding the psychological predictors of phishing susceptibility. The present work aimed to resolve these discrepancies by utilizing a diverse online sample and email set. Participants completed a survey that included an email classification task and measured several individual differences, including phishing awareness, age, impulsivity, curiosity, and personality (the Big-5). Phishing susceptibility was measured by participants' ability to distinguish between phishing and legitimate emails. Three regression analyses were performed to predict email discrimination ability; (1) an age model, (2) a deficient self-regulation model (i.e., impulsivity, response times, and curiosity), and (3) a personality (i.e., the Big-5) model. Overall, phishing susceptibility was predicted by younger age, higher levels of impulsivity and extraversion, lower levels of openness to experience and agreeableness, and quick responses. The present work identifies several populations that are particularly vulnerable to phishing attacks and may require targeted training interventions.