OBJECTIVES DuoResp^® Spiromax^® (budesonide + formoterol fumarate dihydrate) is a fixed-dose combination (FDC) of inhaled corticosteroid (ICS) + long-acting beta agonist (LABA) in a novel dry powder inhaler (DPI).  An economic model was developed to assess the potential societal cost benefits of improved inhalation technique with DuoResp^® Spiromax^® compared with Symbicort^® Turbuhaler^®– a DPI delivering the same FDC – in the management of adult patients with persistent asthma and chronic obstructive pulmonary disease (COPD) in Sweden. METHODS The eligible adult patient population was based on statistics from the National Board of Health and Welfare in Sweden.  Societal costs (lost productivity) were based on the annual number of work-days lost for asthma and COPD patients in Sweden and the United Kingdom (UK), respectively, and the average daily cost of sick leave in Sweden.  Frequency of poor inhalation technique with Symbicort^® Turbuhaler^® and the subsequent increased risk of unscheduled healthcare events were taken from a large (n=1,664) cross-sectional, Italian observational study.  The estimated reduction in the proportion of patients with poor inhalation technique with DuoResp^® Spiromax^® compared with Symbicort^® Turbuhaler^®was based on a conservative assumption. RESULTS An estimated 167,666 adult patients used Symbicort^® Turbuhaler^® annually in Sweden and were therefore eligible for treatment with DuoResp^® Spiromax^®, with 72,935 of these exhibiting poor inhalation technique.  Based on the predicted improvement in inhalation technique with DuoResp^® Spiromax^® compared with Symbicort^® Turbuhaler^® – and assuming a hypothetical uptake of DuoResp^® Spiromax^®reaching 25% in years 4 and 5 – estimated societal cost savings, through the avoidance of 147,158 lost productive days, totalled SEK285.4 million (€31.2 million). CONCLUSIONS DuoResp^® Spiromax^® has the potential to improve inhalation technique compared with Symbicort^® Turbuhaler^®, which would likely result in substantial societal cost savings.