Source characteristics are a key determinant of preferences and choice in the interpersonal influence process. Extant literature documents the positive impact of similarity between oneself and an opinion provider on advice taking, but much less is known about how dissimilarity affects choice. While earlier research assumed that people ignore or discount the opinions of dissimilar others, we argue that dissimilarity can lead to preference and choice contrast. We posit that perceptions of dissimilarity trigger a more general hypothesis of dissimilarity. As a result, a preference contrast is observed, driven by people’s tendency to interpret the provided opinion in a way that confirms their dissimilarity hypothesis. Five studies confirm the emergence of preference and choice contrast due to dissimilarity, and support the proposed mechanism. We discuss the relevance of proper baseline conditions for (dis)similarity research, as well as implications for research within the domain of interpersonal influence.