A bank letter is an official document from your bank that provides important information about your business' official bank account. Go to the EFT Enrollment tab.In the Update EFT Information section near the bottom of the screen: 3. This form is fillable. Type in answers to sections A-D. A bank confirmation letter (BCL) is a correspondence between banks that confirms the existence of a valid line of credit to one of its customers. You'll need to know: Your Bank of America account and ABA routing numbers; Your employer's name and address. Locate my account and routing number. Make sure you use the full formal name of your bank or credit union. They need your banks information-your account number and the banks routing number so that your paycheck will automatically be put into your account.