The routing number on a check is a nine-digit code that identifies the financial institution where the account is held. For instance, on a check from Bank of America, the routing number might be 123456789.
This number is essential for processing electronic payments, such as direct deposits and ACH transfers. It ensures that funds are directed to the correct account and helps prevent fraud. The routing number system was developed in the 1910s by the American Bankers Association to streamline the check-clearing process.