OBJECTIVE: The purpose of the present analysis was to analyze and compare the cost-effectiveness of solifenacin flexible dosing (5-10 mg) with tolterodine 4 mg sustained release (SR) or placebo (assumed to be comparable to no treatment) for patients with overactive bladder (OAB) symptoms. DESIGN: A decision-analytic model was constructed. METHODS: Costs and effects were evaluated for the three treatment options in a one-year timeframe. Costs included were treatment costs, cost of pad use, and patients productivity loss based on data from the Nordic countries. SAMPLE: Results from two randomized controlled trials were used as input data in the cost-effectiveness analysis. MAIN OUTCOME MEASURES: Quality adjusted life years and incremental cost-effectiveness ratio. RESULTS: Solifenacin flexible dosing was more effective with respect to reducing OAB symptoms compared to both placebo and tolterodine 4 mg. Treatment with both solifenacin and tolterodine was more costly compared to placebo, but treatment with solifenacin was a less costly alternative compared to tolterodine 4 mg SR. Sensitivity analyses revealed that the conclusions were robust. CONCLUSION: Solifenacin flexible dosing was a cost-effective treatment alternative compared to tolterodine 4 mg SR.