OBJECTIVES: To assess the health and cost burdens of patients with generalized anxiety disorder (GAD) and other anxiety disorders, including their comorbidities, direct and indirect costs. METHODS: The 1999-2003 MarketScan® claims databases of over three million individuals (annually) were used to identify patients with a diagnosis of GAD, other anxiety disorders (panic disorder, phobias, post traumatic stress disorder, unspecified anxiety state), and demographically-matched controls. Presence of comorbidities, utilization, expenditures, absence and short-term disability (STD) were summarized over a 12-month study period. RESULTS: The prevalence of the following conditions were significantly (p<0.001) higher among the 13,836 GAD subjects and 31,882 other anxiety patients compared to the 89,971 controls: gastrointestinal disorders (19% GAD, 22% other anxiety, 12% controls), genitourinary disorders (40% GAD and other anxiety, 32% controls), cardiovascular disease (10% GAD, 11% other anxiety, 7% controls), and chronic pain (40% GAD, 44% other anxiety, 20% controls). Mean costs for anxiety patients were twice as high as for controls ($6295 GAD, $6800 other anxiety, $3156 controls, p<0.001). These differences were driven by significantly higher rates of office visits and prescription drug use among anxiety patients. Mental health costs for GAD patients ($2031) or other anxiety patients ($2005) did not account for all of the discrepancy. Among the subset of patients with productivity data, anxiety patients had significantly higher indirect costs due to STD days ($2253 GAD, $3255 other anxiety, $934 controls, p<0.001). CONCLUSION: Patients with GAD and other anxiety disorders have significantly higher costs compared to patients without these conditions. The direct and indirect costs of anxiety result from mental health treatment and treatments for physical comorbidities.