Account Number is a unique account identifier allotted by the bank for a customer deposit, loan, or facility account. It is an operational reference rather than an underwriting concept. Mask or secure it because it is sensitive customer information. In MSME credit workflows, it mainly supports clean account mapping, workflow routing, audit trails, reporting and post-disbursement servicing rather than acting as a standalone credit-strength indicator. For example, one CIF may contain separate current-account, cash-credit and term-loan numbers, so capturing the wrong number can make the underwriter review the wrong transactions. It matters because the credit, operations and monitoring teams must all work from the same borrower, facility and account record. The common mistake is to treat it casually as a back-office field; wrong, duplicate or unmasked data can create privacy risk, reconciliation errors and avoidable rework.