The commitment to beliefs (CTB) framework (Maxwell-Smith & Esses, 2012) proposes that there are individual differences in the extent to which people generally follow beliefs that are a reflection of their values. The current research hypothesized that CTB would amplify the effects of perceived belief dissimilarity or incompatibility, such that individuals higher in CTB would display more pronounced reactions to belief-relevant groups, events, or individuals seen as incompatible with their value-based beliefs. We tested our hypothesis in three studies that assessed participants' CTB and their perceptions of belief dissimilarity or incompatibility with regard to other religious groups (Study 1), political parties during a national election (Study 2), and their romantic partner (Study 3). CTB amplified the effects of perceived belief dissimilarity or incompatibility on people's biases toward other religious groups, voting intentions and behavior in a national election, and their evaluative and behavioral responses toward their romantic partner. These results collectively suggest that perceptions of belief dissimilarity or incompatibility are particularly important cues for individuals with higher levels of CTB as they encounter other people or events that are relevant to their beliefs.