Bank routing numbers serve the essential function of identifying what institutions are responsible for paying owed amounts. They are basically the fingerprint of a financial institution, and provide a means of directing transactions between one bank and another. While a current account number belongs to the check-writer or account holder, the routing number belongs to the bank itself. Bank routing numbers are also called routing transit numbers or ABA routing numbers.
According to the American Bankers Association (ABA), bank routing numbers were developed in 1910 to identify check-processing endpoints.
Bank routing numbers are only issued to state or federal chartered financial institutions that are eligible to hold an account at a Federal Reserve Bank, and they serve to identify the institution responsible for payments of a negotiable instrument.
Bank routing numbers are a series of nine digits, located at the bottom of standard checks, just left of the current account number.
In order for a new financial institution to obtain its own bank routing number, the institution must complete and submit an application to Accuity, the official registrar of bank routing numbers.
According to the National Check Fraud Center, it is dangerous to provide an unknown or untrusted person with your bank routing number and current account number, as that information can be used to print out fraudulent checks, putting your finances at risk.