Discrimination based on social class is challenging to study, and therefore likely to be underappreciated due to its subtle nature. Social class is often difficult to gauge from traditional resumes, yet, the expansion of social networking platforms provides employers with an additional source of information. Given that many individuals have a social media presence today, employers can increasingly rely on additional information gleaned from such online platforms (e.g., Twitter, Instagram), which may alter hiring decisions. To study the role of social networking platforms vis-à-vis potential discrimination based on social class cues, I leverage an original online survey experiment in the United States. The aim of the investigation is (i) to measure the effect of cultural markers of social class expressed on social media profiles in a hypothetical hiring situation and (ii) to analyse potential channels that might explain class-based discrimination. I show that subjects favour the upper-class-signalling candidate over the lower-class-signalling candidate and that perceived competence and perceived warmth are two channels through which class-based discrimination may occur. The individual’s online presence might not be part of the formal application process, yet it seems to shape inferences about individuals’ employability, competence, and warmth.