What does NA stand for behind bank name?

Answer 1

National Association. It refers to which government agency granted it its charter (the right to be a bank). Some banks are state chartered, and thus regulated by the state's banking regulations, which can often be more lax than the national regulations. State chartered banks can have a harder time crossing into other states, unless those two states have an agreement to allow it, whereas nationally chartered banks can move into different states (though some restriction do apply). Regardless of its charter the Federal Deposit Insurance Corp is an entity that insures the deposits of both state and national banks, whereas CUNA does it for credit unions.

Answer 2

"NA" stands for "Not Applicable" or "Not Available" when it is listed behind a bank's name. It typically indicates that the bank does not have a specific regulatory or designation requirement.