The estimated total economic cost of OAB was 12.02 billion dollars in 2000, with 9.17 and 2.85 billion dollars incurred in the community and institutions, respectively. Community female and male OAB costs totaled 7.37 and 1.79 billion dollars, respectively. The estimated total cost was sensitive to the estimated prevalence of OAB; therefore, we calculated the average cost per community-dwelling person with OAB, which was 267 dollars per year.