The relationship between social class and mental illness stigma has received little attention in recent years. At the same time, the concept of mental health literacy (MHL) has become an increasingly popular way to frame knowledge and understanding of mental health issues. British Social Attitudes survey data present an opportunity to unpack the relationships between these concepts and social class, an important task given continuing mental health inequalities. Regression analyses were undertaken which centred on depression and schizophrenia vignettes, with an asthma vignette used for comparison. The National Statistics Socio-economic Classification (NS-SEC), education and income were used as indicators of class. A number of interesting findings emerged. Overall, class variables showed a stronger relationship with mental health literacy than stigma. The relationship was gendered such that women with higher levels of education, especially those with a degree, had the lowest levels of stigma and highest levels of MHL. Interestingly, class showed more of an association with stigma for the asthma vignette than it did for both the depression and schizophrenia vignettes, suggesting that mental illness stigma needs to be contextualised alongside physical illness stigma. Education emerged as the key indicator of class, followed by the NS-SEC, with income effects being marginal. These findings have implications for targeting health promotion campaigns and increasing service use in order to reduce mental health inequalities.