The primary difference between a standard bank account number and an IBAN (International Bank Account Number) lies in their scope, structure, and intended usage for financial transactions. A standard account number is a unique sequence of digits assigned by a specific financial institution to identify an individual customer's account within that bank or domestic clearing system. It is generally used for local transactions, direct deposits, and domestic wire transfers. An IBAN, by contrast, is an internationally standardized system created to facilitate the clear, secure routing of cross-border wire transfers. An IBAN incorporates the country code, check digits, the specific bank identifier, and the domestic account number all into one cohesive string. While local account numbers vary wildly in length and format depending on the individual bank and country, an IBAN provides a globally recognized format that minimizes routing errors and prevents failed international payments. Countries like Malaysia do not use IBANs, relying instead on domestic account numbers paired with SWIFT codes.