Sample Bank Confirmation Letter​​ A stamped, self-addressed envelope is enclosed for your convenience. In this article, we discuss how to write a conformational letter, look at sample templates for formal and informal confirmation letters and share some tips.FORMAT OF BANKER'S VERIFICATION LETTER. Confirmation provides an easy-to-use, secure online platform. With your days so busy and life so full, you need a bank that can keep up with the lightning pace of change. Background: High response rates are needed in populationbased studies, as nonresponse reduces effective sample size and.