In this article, we walk you through all the steps to writing and formatting the letter, including a sample and a template. This article will give you the reasons why you should close your bank account.Sample account closing letters are also given for your better understanding. How Do Bank Closure Letters Work? I need a sample letter to request a formal accounting of an estate and of a trust that I am very confident the trustee. Want to close a bank account? You might need to submit a written request. Please accept this letter as my written authorization to close the following account(s) at your financial institution. Notice to Eligible Institution Form (Submit to bank. Must be kept on file.) Sample Trust Account Bank Notification Letter (Submit to bank.