When assessing Corporate Social Responsibility (CSR) and its impact on company performance there may be an informational asymmetry caused by differences in Familiarity with the firm assessed. This study uses participants' ratings of six large UK retailers to establish the direct relationships between the CSR components of Economic, Legal, Ethical, and Discretionary, and the firm performance dimensions of Reputation, Trust, and Customer Satisfaction, then explores whether Familiarity mediates the relationships between the CSR and the performance dimensions. The findings show CSR Economic, Legal, and Discretionary are associated with firm Reputation and Trust, but not Customer Satisfaction, and that CSR Ethical is associated with Reputation, Trust, and Customer Satisfaction. Familiarity acts as a mediator between CSR Economic, Legal and Discretionary, and Trust and Customer Satisfaction. Familiarity also mediates the relationship between CSR Discretionary and Reputation. The link between CSR Economic and Legal, and Customer Satisfaction only emerges in mediation analysis. Managerial implications suggest increasing familiarity is vital through open and continuous communication about CSR programs is essential to keep customers aware. Methodological implications propose reevaluating the methods used to measure (CSR), taking into consideration its' multi‐faceted nature and the diverse impacts that different aspects have on familiarity and performance measures.