Substantial evidence from randomised clinical trials has demonstrated that long-acting risperidone (RLAI) is efficacious and well tolerated in patients with schizophrenia. Recently, a long-term naturalistic study of treatment practices in Belgium, the electronic Schizophrenia Treatment Adherence Registry (e-STAR), reported that treatment with RLAI is associated with improvements in adherence and long-term outcomes. The present report describes the results of a budget impact model that analysed the Belgian e-STAR data, together with other available data, over a 3-year time horizon, in order to establish the potential impact of treatment with RLAI on total healthcare costs in Belgium.The model framework combined medical resource utilisation with costs of the population of interest in order to quantify the costs, and cost offsets, of RLAI treatment. For the purpose of this budget impact model, it was assumed that among patients who would discontinue their previous antipsychotic medication, 6.7% of patients would be switched to RLAI. The overall cost savings to the Belgian healthcare system were calculated to be 2.3 million Euros in Year 1, 3.7 million Euros in Year 2 and 4.4 million Euros in Year 3. The majority of these cost-savings resulted from the substantial reduction in hospitalisation costs associated with RLAI treatment. This report indicates that improvements in adherence and long-term outcomes previously demonstrated for RLAI treatment in Belgium may result in substantial cost benefits to the country's healthcare system.