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.Closing the Estate of the Person who Died. You may use the forms on this page if the following factors apply to your situation. Online: Use our online form to notify us about a customer's death. Question: My mother passed away. She does have a will and I was nominated as the executer and trustee. The deceased had no Will, but I am entitled to the property under law because (check ONE) I am the spouse of the person who died; You need to take your mother's death certificate to the bank. Get an executor checklist to help with settling an estate.