OBJECTIVES: To assess the economic impact of introducing beclomethasone/formoterol extrafine for the treatment of moderate to severe persistent asthma in six Spanish regions including Andalusia, Bask Country, Catalonia, Galicia, Madrid and Valencia. METHODS: A budget impact model was developed using the perspective of the Spanish regional healthcare services with a 5-year time horizon. The model was populated with regional data on disease prevalence, population growth, drug tariffs, healthcare resource utilization, unit costs and market shares. Drugs considered in the study were fluticasone/salmeterol, budesonide/formoterol and beclomethasone/formoterol extrafine. Costs considered included drug costs, diagnostic tests, physician visits, hospitalisation and adverse effects treatment costs. All costs referred to EUR 2010, using a 5% annual discount rate. Total annual healthcare costs were estimated based on mean costs per patient for each treatment before and after the introduction of beclomethasone/formoterol extrafine. RESULTS: Based upon the Spanish adult population data and asthma prevalence, the treated population with moderate to severe persistent asthma in 2010 was estimated at 110,346 in Andalusia, at 16,369 in the Bask Country, at 31,118 in Catalonia, at 30,506 in Galicia, at 21,800 in Madrid and at 37,316 in Valencia versus populations of 140,684, 19,893, 38,378, 37,753, 27,660 and 46,789 respectively in 2015. The annual mean cost per patient was €996 before the introduction of beclomethasone/formoterol extrafine and €990 after its introduction. Total annual health care costs over the next 5 years for all six regions range between €95,7 and €661,6 million for the Bask Country and Andalucia before the introduction of beclomethasone/formoterol extrafine and €95,1 and €657,9 million after its introduction, respectively.  CONCLUSIONS: The introduction of beclomethasone/formoterol extrafine for the treatment of moderate to severe persistent asthma showed to reduce the budget impact for each of the regional health care services by showing net savings for all six regions over the next 5 years.