The main purpose of this paper is to assess the cost-efficiency of Banco Ciudad de Buenos Aires’s bank branches using a Stochastic Frontier Analysis (SFA). With the results, management can decide on new branching dimension. Also, if some regulatory or managerial limits could be lift, such as closure or opening of new branches without the central bank authorization, or redundant staff reduction, the results could be important for management. We detect best and worst behaved branches. The more cost-efficient branches and the least cost-efficient ones differ in their size and input mix. Nonetheless, they present a similar output mix.