Objective: To evaluate the cost-effectiveness of adding individualized occupational therapy (IOT) to group occupational therapy (GOT) as standard care versus GOT alone for prevention of rehospitalization for patients with schizophrenia. Methods: Data were collected from our previous randomized controlled trial from baseline psychiatric discharge to 2-year follow-up. The effectiveness was measured as the number of patients who were not rehospitalized, and the cost outcome was defined as direct medical costs. Results: A total of 109 patients were included: 53 in GOT + IOT and 56 in GOT alone. The number of patients who avoided rehospitalization was significantly higher in the GOT + IOT (n = 37) condition compared with the GOT alone condition (n = 16) (p < .001). Adding IOT to GOT was associated with a 56.76% probability of being more effective at reducing the rehospitalization rate and a 26.93% probability of being less costly than GOT alone. GOT + IOT had high outpatient costs, but lower inpatient costs due to the lower rehospitalization rate; as a result, total medical costs were lower than for GOT alone. Conclusions: Our results demonstrate that adding IOT to GOT is likely to reduce costs and the rehospitalization rate; thus, GOT + IOT is more cost-effective than GOT alone.