REQUIRED – Voided Check or Bank Letter: Bank Letter Requirements. On the Bank's Letterhead; Legal name on the account; Bank routing number; Bank account number.A bank letter is an official document from your bank that provides important information about your business' official bank account. Bank Letter – A letter on bank letterhead that formally certifies the account owner's routing and account numbers. To make an IBAN, banks combine local account details into one string of characters. This means you can calculate an IBAN using these account details. You will need to become the estate's administrator or executor to gain access or information to the deceased person's bank account. We need the information to send your U.S. Social Security payments electronically to your Georgia bank account. You can open an account with the help of Mobilbank or in any of our branches. What are account packages?