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R66 ACH Return Code: Incorrect Company Identification

Read Time: 2 min

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ACH return code R66 is used to indicate a specific type of error or problem with an Automated Clearing House (ACH) payment. The ACH Network, which NACHA governs, issues codes to describe the underlying error preventing an ACH payment from processing. An understanding of ACH return codes is crucial, as there are numerous possible processing errors that can result in a return.

Whether you’re a seasoned pro or brand new to the ACH world, we’re here to help you navigate the error code you’re seeing. Below, we dive deep into ACH return code R66 to explain why it occurs and how to solve it.

What Does ACH Return Code R66 Mean?

As the name suggests, an ACH return is a return of an ACH transaction. NACHA guidelines stipulate that a Receiving Depository Financial Institution (RDFI) can only initiate returns during predetermined times. Meanwhile, the Originating Depository Financial Institution (ODFI) is the institution that initiated the transaction. Together, the RDFI and ODFI work together to process secure transactions through the ACH Network.

ACH files include the company name and the associated batch number, a unique number assigned to each company/batch header. ACH return code R66 pops up when there’s a discrepancy between the company identification number used in the original transaction and the company identification number used in the company/batch header used in the returned transaction.

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Formal definition

The formal definition for ACH return code R66 — Incorrect Company Identification is as follows:

The Company ID number used in the Company/Batch Header Record of the Return is different from the ID number used in the original entry.

Solutions to Fix R66 Return Code

Should you receive ACH return code R66, contact the ACH operations group at the RDFI immediately. Let the operator know that the company identification number on the return differs from the one on the original transaction. After providing any necessary transaction information, ask the agent if they can reverse the return. After the return reversal, you can initiate a new return with the correct company identification number and continue smoothly accepting ACH payments.

a hand writing a check after an R66 ACH return code problem was resolved

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