Background: Modified Assertive Community Treatment (ACT) in rural settings may be effective in the care of patients with severe mental illness (SMI) that are difficult to engage in community care. The objective of the present study was to explore the impact of the care by a hybrid ACT team on SMI patients’ hospitalizations, length of hospital stay, symptomatology and functioning in a rural community treatment setting in Greece. Methods: The hybrid ACT team is an expansion of the services of the well-established generic Mobile Mental Health Unit in a rural area of Northwest Greece, and delivers home-based care for patients with SMI. This was a 3-year prospective, mirror image, pre-post observational study. Patients’ symptomatology, functioning and general outcome were measured with the use of the Brief Psychiatric Rating Scale (BPRS), the Global Assessment of Functioning Scale (GAF), and the Health of the Nation Outcome Scale (HοNOS). Results: The mean age of the 23 enrolled patients was 52.4 years and the mean age of disease onset was 23.5 years, with a mean number of hospitalizations 10.74. Over the 16-month follow-up patients’ hospitalizations, both voluntary and involuntary, had been significantly reduced by almost 80%. Length of hospital stay had been significantly reduced by 87%, whereas patients’ functioning and symptomatology had been significantly improved, by 17% and 14.5%, respectively. Conclusions: The model of hybrid ACT in rural areas in Greece may be effective in the treatment of difficult-to-engage patients with SMI and may improve patients’ outcomes.