The ACH Audit Guide is a publication designed to assist financial institutions in completing an annual ACH audit as required by the Nacha Operating Rules. This is a working document that will walk you through the steps of completing an ACH audit along with reviewing sound business practices, related compliance areas, online banking products, and government benefit payments. An audit preparation checklist is included to assist in gathering information needed for review. The document includes tools to help the auditor understand ACH participants, payment applications, and recent revisions to the Nacha Operating Rules. Electronic Version