ACH Code R15 - What is this?

The ACH return code R15 indicates that a financial institution has received an ACH (Automated Clearing House) entry that duplicates a previous entry. This code is used by the RDFI (Receiving Depository Financial Institution) to notify the ODFI (Originating Depository Financial Institution) that the entry has been returned.
”Return of XCK” refers to the terminology used in the banking industry to indicate that the entry is being returned because it duplicates a previously processed entry. XCK stands for “Excessive Entry” and is a term used to describe a situation where multiple entries are submitted for the same payment, resulting in duplicate transactions.

In summary, the ACH return code R15 with the memo “Return of XCK” indicates that a financial institution has received a duplicate ACH entry and is returning it to the ODFI. This code is used to prevent double posting of transactions and ensure the accuracy of the ACH system.