re: Confidentiality for bank tellers

It depends on the bank. My bank had a confidentiality policy in the employee handbook which stated that it was grounds for termination for ANY bank employee to divulge a customer's information, including account balances with the bank (loans and deposits), who the customer's customers were and if the customer was late on any payment or had any problems with the bank.

I had to fire an employee (not a teller) for making an offhand comment at a Christmas party about a customer's relationship with our bank in front of the customer and other persons and the customer complained the next day about his financial information being talked about so casually.

You can ask the branch manager where you bank about that bank's confidentiality policies.