Sample Letter to Bank Informing the Death of the Account Holder. The death claim letter should be written in the formal letter format.Use our Affidavit of Death form to verify the death of a family member and help with the inheritance process. 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. Closing a bank account when someone passes away isn't difficult, as long as you have the right paperwork for the the teller or banker. A letter indicating that there are sufficient funds in the Estate to pay funeral costs may be required. Keep all contracts and receipts from the funeral home. Online: Use our online form to notify us about a customer's death. We'll need a photocopy of the death certificate to verify the identity and legal residence of your loved one as well as confirm date of death.