ACH-NACHA Correction and Reject Codes
Correction Codes begin with the letter C and indicate that some of the information provided in a transaction was not correct. However, in these cases, the bank will have identified the correct information, accepted the transaction, and provided the corrected information back to you. Please update your records with the corrected info.
ACH-NACHA Change Reason Correction Codes.pdf
Return Codes begin with the letter R, X, or E and indicate that a transaction has not been processed by the customer's bank and payment was not collected from or credited to your customer’s account. Depending on the reason for the rejection, some transactions may be corrected and resubmitted.
Return Codes with Definitions (2020).pdf