In light of healthcare reforms, the study aims to assess variables associated with mental healthcare service utilization in general and in both primary and specialized care by patients with severe mental disorders (SMD, mainly schizophrenia). The study is based on a sample of 140 patients with SMD from five regions in Quebec (Canada). Variables were organized in accordance with Andersen's conceptual model into four factors: predisposing, enabling, needs, and service utilization. Secondary analyses were also conducted comparing patients who were hospitalized or used emergency rooms (H.ER-Group) with patients who did not use such services (WH.ER-Group). Accessibility of services, continuity of care, and having a case manager appear to be core variables that enable service utilization. Compared with the WH.ER-Group, the H.ER-Group used twice as many services. The study highlights the importance of developing a gamut of coordinated services, easily accessible in local networks, including case managers, family physicians, and shared-care development.