To close a bank account on behalf of someone who has passed away, you must have legal authority to manage the account. (Arizona Revised Statutes, Section 14-3971)You would simply get the form and instructions from the court's website, fill out the form and have it notarized.Online: Use our online form to notify us about a customer's death. You'll need the person's Social Security number and certified copies of their death certificate for most agencies and programs. Social Security and Medicare. I am named in the Will of the person who died, a copy of which is attached to this Affidavit. You'll need the original or certified copy of the appointment letter naming you as the personal representative of the estate along with any additional court-. They went back and took the money out of our account after her death. Call the Local Banks: You can call local banks to find out whether the deceased had any accounts. You need to take your mother's death certificate to the bank.