An interesting new result relate to factors influencing cost and profit efficiencies. Both bank size and bank credit risk (non-performing loans) negatively affect cost and profit efficiencies. It is a long-running explanation that Indonesian banking practices appear to have poor credit risk assessment mainly because of the capture of banks by real sector conglomerates However, the influence is not statistically significant in the case of cost inefficiency. But, both factors have statistically significant and negative influence on profit inefficiency. This study does not include banks not listed on the share market, so the findings are not generalisable to all banks. However, banks included in this study account for 80 percent of the total assets of all the banks, hence, the findings has validity for the sector.