Poverty is associated with higher rates of mental illness and lower levels of well-being. Poverty affects mental health and well-being through a range of mechanisms, one of which may be experiences of stigma associated with living in poverty or accessing services designed to assist individuals on low incomes (including social security). The aim of this study was to synthesise published research on the relationship between individuals’ experiences of poverty stigma and aspects of mental health and well-being. A rapid review was undertaken of quantitative and qualitative research published between January 2005 and February 2021. In total, 22 (5 quantitative and 17 qualitative or mixed methods) studies met the inclusion criteria, the findings of which were extracted and analysed using thematic synthesis. Experiences of poverty stigma were found to be associated with four broad aspects of mental health and well-being: negative self-evaluations, diminished social well-being, negative affect, and mental ill-health. Several forms of poverty stigma, including self, received, perceived, anticipated, and endorsed stigma were implicated in these associations. Poverty stigma may contribute to inequalities in mental illness and well-being, although further quantitative and longitudinal research is required to test its impact on mental health.