OBJECTIVE: The Australian climate has warmed by 1.51°C since preindustrial times, and the Commonwealth Scientific and Industrial Research Organisation (CSIRO) predicts further warming with an increased risk of extreme heat events. This article discusses how the most recent Royal Australian and New Zealand College of Psychiatrists' (RANZCP) position statement dealt with the impact of climate change-related heat stress on people living with severe mental illness. CONCLUSIONS: The RANZCP statement focuses on the impact of climate change on common mental disorders and suicide rates without specific mention of severe mental illnesses such as schizophrenia, bipolar disorder and severe major depression. However, people with severe mental illness face higher risks of morbidity and mortality in a hotter Australian climate. Based on equity for those with greater needs and higher levels of risk, we argue that psychiatrists should advocate for enhanced social and psychiatric care to improve heat-resilience amongst patients with severe mental illness. Future research is needed on the biopsychosocial mechanisms of increased heat-related morbidity and mortality for people with severe mental illness.