OBJECTIVES: Results of recent studies have demonstrated that pharmaceutical care can lead to significant improvements in the control of fasting plasma glucose and hemoglobin A1c (HbA1c) in type 2 diabetic patients. This study aims to assess the cost-effectiveness of pharmaceutical care in type 2 diabetic patients in Ribeirão Preto, Brasil, compared with the conventional care provided just by a physician (status quo). METHODS: A prospective and experimental study with seventy-one patients divided into two groups: control and pharmaceutical care developed by the Pharmaceutical Assistance and Clinical Pharmacy Research Center (Borges, 2008) was used as data base for this study. Patients in the pharmaceutical care group were followed up monthly by a single clinical pharmacist during 18 months, from March 2006 until August 2007. Thereafter, medical records were collected until 2011, including: HbA1c, fasting plasma glucose, medication consumption, number of physician visits, diabetes complications and date of death. All analyses were taken from the government’s health policy perspective. Cost of diabetes was calculated based on the government reimbursement rates and adjusted for inflation until 2015. Cost-effectiveness analysis were performed as incremental cost per patient with controlled HbA1c. According to WHO, the patient’s HbA1c is considered controlled when its value is less or equal to 7%. A series of sensitive analyses were also performed. RESULTS: The pharmaceutical care group had lower costs, R$ 5,170.92 (US$ 1,293.28), and higher effectiveness (39%) compared to the conventional group, that presented costs of R$ 11,351.18 (US$ 2,839.00) and effectiveness of 21%. For the period of 2007-2011, the ICER presented a saving of R$ 33,795.77 (US$ 8,452.53) per patient with controlled HbA1c. CONCLUSIONS: Our findings showed that in type 2 diabetic patients, the pharmaceutical care is a dominant intervention, increasing rates of HbA1C control and reducing treatment costs.