You will also need to provide a certified copy of the death certificate. The bank will not allow you to close it unless you have a letter of authorization from the probate court.A bank closure letter may be needed if you want to close a bank account without having to go to your bank's physical location. Learn how to close accounts of deceased persons when you are the executor of an estate. You have to write an application to the bank. Online: Use our online form to notify us about a customer's death. When you've registered the death, you will be issued with a death certificate. This will act as formal notification for the bank to begin closing the account.