OBJECTIVES: To estimate the budget impact of introducing indacaterol in the treatment of COPD over a 5-year time horizon in patients eligible for treatment with long-acting maintenance therapy. METHODS: An Excel-based budget impact model was developed to calculate the budget impact based on local epidemiological and drug costs data. The number of patients eligible for treatment with long-acting maintenance therapy was estimated considering: 1) the local adult population (>40 years old) of approximately 14.5 millions; 2) proportion of population using the public healthcare system services and medications around 77%; 3) prevalence of local COPD patients about 15.8%; 4) 18% of these patients are diagnosed and receiving treatment; 5) 1.05% of annual population growth rate; 6) the same patient distribution in each disease severity across all years was assumed as 64% of mild, 29% of moderate, 6% of severe and 1% of very severe; 7) only patients in moderate, severe and very severe groups were considered as eligible for treatment with long-acting maintenance therapy; and 8) 53% of annual treatment persistence rate was applied. The ex-factory price with 24.38% of discount was used for indacaterol costs and 5% of annual discount rate was applied on the costs. Indacaterol 150µg uptake was assumed to be: 10%, 15%, 20%, 23%, 25%, over 5 years consecutively. RESULTS: The number of patients eligible for treatment with long-acting maintenance therapy in São Paulo was estimated to be around 60,754 in the first year. The annual net budget impact of indacaterol was negative through the years around: -88K, -1.7M, -3.2M, -4.2M and -4.4M (BRL) consecutively. CONCLUSIONS: The budget impact results show that indacaterol has potential to reduce costs on the budget of State health care system.