The objective of this study was to audit the cost of flexible ureterorenoscopic lithotripsy. The data for 302 consecutive flexible ureteroscopic lithotripsy (FURSL) procedure undertaken in our department for renal stone treatment were collected retrospectively. The costs associated with performing FURSL, including the cost of ancillary equipment were analyzed. This includes the cost of the initial purchase of the ureterorenoscopes and the holmium laser equipment. The cost of flexible ureterorenoscopy for each lithotripsy procedure (for a total of 302 FURSL) was $118. Additional cost of ancillary equipment including laser device, ureteral acces sheath and stone retrival catheter were $156, $231 and $611, respectively. In this series, the costs of the ancillary equipment including laser exceeded the purchase and maintenance of the flexible ureteroscope. The cost of disposables rather than flexible ureteroscope itself should be considered in planning the budget.