A bank letter is an official document from your bank that provides important information about your business' official bank account. How do I sign up for Direct Deposit?Fill out this authorization agreement along with verification from the bank showing the account number and routing numbers. This letter is to confirm that our client Hey Reb currently holds a checking account with us. For your convenience, we have several forms that you can download and fill out. This letter constitutes your ten (10) day written notice that your check was returned marked. Fill in the details for your new template. Include Source Account, Description, and default amounts for each recipient who should be included. When completing the next page of this document it is important to understand what the qualifications are for opening an account and becoming a signer. This guide will take you through each step of the process, from selecting the right bank to completing the necessary paperwork.