Much research has demonstrated that Democrats and Republicans use information about party affiliation to discriminate against one another. However, we know little about how people gain the necessary information about other people’s partisanship to engage in discriminatory behavior. We explore whether people perceive partisanship when shown only images of faces, and whether they then use these perceptions to engage in partisan discrimination. We find that they do. Using two studies we show that the partisan perceptions people derive from seeing images of faces influence discrimination of job applicants, and propensities to engage is a wide range of social interactions. People appear to be making judgements about partisanship using only facial appearance, and are willing act on that perception. The implication of this finding is that partisan discrimination is likely widespread, and does not require the explicit communication of partisan affiliations.