OBJECTIVES The objective was to evaluate the direct and indirect costs of asthma in working US adults. METHODS Asthma patients with ≥1 primary asthma diagnosis, or ≥1 asthma diagnosis any level and ≥1 asthma prescription, or ≥2 asthma diagnoses any level between January 2003 and December 2005 in the Thomson Reuters MarketScan® Commercial Database and Health and Productivity Management Database were extracted. Patients were 18-64 years old, had full-time employment, were eligible for absence, or short-term disability (STD), or workers' compensation (WC) and were continuously enrolled 12-month pre/post the index date (first asthma diagnosis or asthma medication claim). Those with emphysema or COPD were excluded. The controls had no asthma claim and met the same inclusion and exclusion criteria. An index date was assigned to controls by adding a number to January 2003 that was randomly drawn from a pool of days between January 2003 and index date for each asthma patient. Propensity score techniques were used to match asthma patients to controls based on baseline demographic and clinical characteristics. RESULTS A total of 13,379 asthma patients were matched to 13,379 controls comprising of 3,453 patients with absence eligibility, 8,497 with STD eligibility and 8,264 with WC eligibility in each of the asthma and control group. Most baseline characteristics after matching were very similar. Asthma patients had $1,988 higher direct medical costs than matched controls (p<0.001) during the 12-month follow up. They experienced 1.2 more absence days (p=0.0142), 2.2 more STD days (p<0.001) and 1.3 more WC days (p<0.001) than controls. This translated into $166 (p=0.041), $248 (p<0.001) and $59 (p=0.009) more in indirect costs respectively. CONCLUSIONS Asthma patients experience significantly greater work loss and medical costs than patients without asthma. Asthma treatments can potentially benefit in reducing absenteeism and costs.