AIMS: The aim of this study was to identify the risk correlates for coexisting common mental disorders (CMDs) in the chronic care population in South Africa, with the view to identifying particularly vulnerable patient populations. METHODS: The sample comprised 2549 chronic care patients enrolled in the baseline and endline rounds of a facility detection survey conducted by the Programme for Improving Mental Health Care in three large facilities in the Dr Kenneth Kaunda district in the North West province of South Africa. Participants were screened for depression using the Patient Health Questionnaire (PHQ9) and for alcohol misuse using the Alcohol Use Disorders Identification Test (AUDIT). Data were analysed according to the number of morbidities, disorder type (physical or mental) and demographic variables. Multimorbidity was defined as the presence of two or more disorders (physical and/or mental). RESULTS: Just over one-third of the sample reported two or more physical conditions. Women were more at risk of being depressed than were men, with men more at risk of alcohol misuse. Those who were employed were at lower risk of having coexisting CMDs, while being younger, HIV positive, and food deprived were all found to be associated with higher risk for having coexisting CMDs. CONCLUSION: In the face of the large treatment gap for CMDs in South Africa, and the role that coexisting CMDs can play in exacerbating the burden of chronic physical diseases, mental health screening and treatment interventions should target HIV-positive, younger patients living in circumstances where there is household food insecurity.