I understand that we are allowed to return an ACH item within 60 days of it posting to an account. If a customer comes in on July 10 and states that they withdrew authorization for a business to debit their account on July 1, can we return an item that hit their account on June 25? I just want to make sure that we can in fact return an item that posted to a customer's account before they actually withdrew authorization for a business to debit their account.

NACHA rules stipulate that you may return an unauthorized entry up to 60 days after the date of debit. However, a customer can't withdraw authorization on a payment after it has settled. Per NACHA, authorization may be revoked up to 2 days before settlement date, but never after. If you try to return this using "unauthorized," you open your bank up to problems. Additionally, the customer must fill out a "statement under penalty of perjury" that the authorization was revoked prior to settlement date.

This is about the same as asking a bank to stop payment on a check that cleared five days ago. The revocation of authorization cannot be retroactive.