On Main Street in Smalltown, USA, there are two banks that operate across the street from each other on the same block. Both banks are being audited, but have different agencies auditing each bank. What is the best explanation for this? Both banks are credit unions. One bank is a National Bank and one bank is a Federal Savings Association. Both banks are federally chartered, but one is regulated by the FED and the other is regulated by the FDIC. One bank is federally chartered and one bank is state-chartered.