People with mental illness have substantially lower life expectancy than the general population, with mortality from natural causes most commonly attributed to cardiovascular diseases. The study aim was to identify characteristics of consumers who died of natural causes between 2009 and 2018 at one of Australia’s largest publicly funded mental health services. Data were collected with a retrospective medical record review of 102 consumers. Mean mortality age was 52.4 years (SD = 10.7) (with females 51.9 years [SD = 12.0], and males 52.7 years [SD = 9.9]), which was more than 30 years lower than the Australian population. Cardiovascular diseases were the most frequent mortality cause (39%), followed by respiratory conditions (23%), cancers (20%), and all other causes (19%). Sixty (61%) consumers had at least three co‐occurring physical health conditions. Seventy‐five (74%) smoked tobacco. Consumers who died from cardiovascular diseases were less likely to attend specialist medical follow‐up for their condition (P = 0.004), and more likely to die at home (P = 0.001). Consumers whose mortality age was above 55 years were more likely to have three co‐occurring physical health conditions (P = 0.034). Consumers whose mortality age was below 55 years were more likely to have sub‐optimal nutritional intake (P = 0.014) and higher body mass index (P = 0.008). There is a critical need to close the life expectancy gap for consumers. This requires dedicated focus on reducing mortality risk due to modifiable clinical characteristics which lead to consumer mortality. Mental health nurses play a key role in helping reduce consumers’ mortality and morbidity risk through prevention and early intervention strategies.