This paper considers the relationship between a core brand built around retail operations and an extension built around financial services operations. The fundamental question that underlies the paper asks whether a successful/unsuccessful implementation of financial services brand extension impacts positively/negatively on the core retail brand. Findings from over 1000 responses indicate that the retailer brand extensions under investigation do have a significant impact on the core brand. Further analysis, using customers who have experienced the brand extension versus those that have not, reveals that this impact can be negative as well as positive. That is, where a customer perceives the brand extension to be implemented poorly the relationship between the customer and the original brand is compromised.