Duplicate Entry
Category: Format & data Initiated by: RDFI
Read reinitiation conditions and source →Applies to (SEC scope)
ALL
camt.053 mapping
AM05 — Duplication
Nacha's definition
The RDFI has received what appears to be a duplicate Entry i.e., the trace number, date, dollar amount and/or other data matches another transaction.
Verbatim from Nacha — ISO 20022 Guide to Mapping U.S. ACH Return Items and Notifications of Change, August 2023, Version 2.01 (Table 1, return reason codes) (return reason code table). Applies to: ALL.
Reinitiation conditions
Nacha's reinitiation rule page allows reinitiation "to correct administrative errors", with fields other than Company Name, Company ID and Amount modified only to the extent necessary. A corrected resubmission of a returned debit is therefore treated as a reinitiation, within the Rules' limits and carrying RETRY PYMT. Nacha's reinitiation rule addresses returned debits; a returned credit falls outside it.
correct the field the RDFI identified, and code the resubmission correctly.
How it appears in an ISO 20022 statement
Nacha's mapping guide maps R24 to camt.053 reason code AM05 (Duplication) — ISO definition: Duplication.
Return time frame
Nacha's public rule pages refer to the standard "two-day" return time frame for returns that are not extended (unauthorized) returns. The current Nacha Operating Rules and your ODFI determine the applicable deadline for this code; a general public two-day reference is not a substitute for that code-specific requirement.
What an operator does next
The RDFI believes this is a duplicate. Check your own origination logs for a double send before reissuing anything; if the original posted, do not send again.
PaymentBrief guidance, not Nacha text. Your ODFI's procedures and the current Nacha Operating Rules govern.
Where this comes up on PaymentBrief
Sources for this code
- Nacha — ISO 20022 Guide to Mapping U.S. ACH Return Items and Notifications of Change, August 2023, Version 2.01 (Table 1, return reason codes) — retrieved 2026-09-06
- Nacha — rule page 'ACH Network Risk and Enforcement Topics' (unauthorized return rate threshold; reinitiation of entries) — retrieved 2026-09-06