The Office of the Comptroller of the Currency (OCC) is an independent bureau of the U.S. Department of the Treasury that charters, regulates, and supervises all national banks, federal savings associations, and federal branches and agencies of foreign banks. Its core responsibilities include ensuring supervised institutions operate in a safe and sound financial manner, guaranteeing fair access to financial services, enforcing adherence to applicable banking laws and regulations, and approving or denying new bank charters, brand setups, mergers, and conversions.