OBJECTIVES: Existing projections of the cost of overactive bladder (OAB) in the United States (US) are incomplete and outdated. We sought to determine the cost of OAB in the US from a societal perspective, incorporating direct medical, direct non-medical, and indirect costs. METHODS: We developed a prevalence-based model with data on age- and sex-specific OAB prevalence, health care utilization, other components of care, and productivity. Using data from the five most recent years of medical literature, practice guidelines, Medicare and managed care fee schedules, and expert panel input, we calculated the annual per capita and total US costs. Direct costs were calculated as the product of the age/sex-specific probability that a care component is used, the age/sex-specific number of units used, and its unit price. Indirect costs (lost productivity) were calculated based on the human capital model and governmental census data. We applied current age/sex-specific prevalence rates, treatment patterns, and costs to US census population projections to project costs of OAB in 2015 and 2020. RESULTS: Mean total annual per capita cost in 2007 was $1991, comprised of $1500 (direct medical), $66 (direct non-medical), and $426 (indirect). Given that about 34 million people in the US have OAB, the total national cost is $68.2 billion (B) ($51.4B direct medical, $2.3B direct non-medical, and $14.6B indirect). Mean total annual per capita costs in 2015 and 2020 would be $2010 and $2036 respectively. Given projections of ~39 million and 42 million people with OAB in 2015 and 2020, total national costs would be $78.8B and $85.4B, respectively. CONCLUSIONS: These data suggest that the economic burden of OAB is about five-fold higher than older, non-comprehensive estimates. Inasmuch as 75% of this cost is for direct medical care, it is important that opportunities be explored to improve the value of available therapies.