People with severe mental illness have significantly reduced life expectancy and higher risk of cardiovascular diseases than the general population. There is a critical need for quality physical health care to improve consumers’ health outcomes. There is minimal knowledge, however, on the impact of mental health nurse practitioner candidate (NPC) practices on consumers’ health outcomes. The aim of this proof‐of‐concept study was to describe the impacts of NPC practices on the quality of physical healthcare provision and physical health outcomes (cardiovascular and cardiometabolic) of consumers in community mental health service settings. Using a mixed methods design, quantitative data were collected for 12 months prior to (Period 1), and 12 months during (Period 2), the candidacy period. Qualitative interviews were conducted with a purposive sample of n = 10 consumers to explore their perspectives on physical healthcare provision by the NPCs. During the 12‐month candidacy period, the number of metabolic monitoring assessments rose from n = 55 in Period 1 to n = 146 in Period 2 (P < 0.01, χ2 = 41.20). Advanced practices provided by NPCs included taking an extensive holistic history and clinical examination, ordering diagnostic pathology, and clinical simulation of physical health medication prescription (under medical supervision). Analysis of consumer interviews resulted in two themes: (i) positive and helpful NPC health care and (ii) improvements in physical and mental health. The findings add new knowledge on specialist mental health nurse practitioner candidate roles and demonstrate the benefits these roles can have in reducing the significant morbidity and mortality of mental health consumers.