Sample Letter to Bank Informing the Death of the Account Holder. The death claim letter should be written in the formal letter format.This is to notify the bank that my. (Relationship with deceased). In New York State, the Surrogate's Court decides what happens to a person's property when that person dies. You should also make a list of what the Decedent owned at the time of death (such as bank accounts, house, stocks, etc.). Start the letter with your introduction and the reason for writing the letter. We've got the answers in our FAQs. I need to write to several organisations including banks, insurance and mortgager company to inform them of my partners death.