What does DU01 mean in ISO 20022?

DU01 is Duplicate Message ID in the ExternalStatusReason1Code code set: Message Identification is not unique.

Where does DU01 appear in a message?

For example in pacs.002, element TxInfAndSts/StsRsnInf/Rsn/Cd.

ExternalStatusReason1Code

DU01 Reason Code: Duplicate Message ID

Written and maintained by ZagTrader. Last reviewed 21 October 2026. How this page is sourced and checked

DU01 means duplicate message id in the ISO 20022 status reason code set. Message Identification is not unique.

Code: DU01
ISO name: DuplicateMessageID
Status: Registered
Last updated: 2010-08-01

Official definition

Message Identification is not unique.

Definition from the ISO 20022 External Code Sets, 2Q2026 (published 28 Aug 2026).

Messages and fields that use ExternalStatusReason1Code

Message	Element path
pacs.002	TxInfAndSts/StsRsnInf/Rsn/Cd, OrgnlGrpInfAndSts/StsRsnInf/Rsn/Cd
pain.002	OrgnlGrpInfAndSts/StsRsnInf/Rsn/Cd, OrgnlPmtInfAndSts/StsRsnInf/Rsn/Cd, OrgnlPmtInfAndSts/TxInfAndSts/StsRsnInf/Rsn/Cd
auth.027	GrpSts/StsRsn/Rsn/Cd, PackgSts/StsRsn/Rsn/Cd, PackgSts/RcrdSts/StsRsn/Rsn/Cd
camt.025	RctDtls/ReqHdlg/StsRsn/Rsn/Cd
camt.111	InvstgtnRspn/InvstgtnData/RspnData/TxSts/StsRsnInf/Rsn/Cd
pain.014	OrgnlGrpInfAndSts/StsRsnInf/Rsn/Cd, OrgnlPmtInfAndSts/StsRsnInf/Rsn/Cd, OrgnlPmtInfAndSts/TxInfAndSts/StsRsnInf/Rsn/Cd
reda.016	PtySts/StsRsn/Rsn/Cd
reda.020	SctiesAcctSts/StsRsn/Rsn/Cd
reda.047	SctyCSDLkSts/StsRsn/Rsn/Cd
reda.051	AcctLkSts/StsRsn/Rsn/Cd

And 8 more messages: see the ExternalStatusReason1Code page.

DU01 in other code sets

DU01 in ExternalInvestigationStatusReason1Code

DU01 questions

What does DU01 mean in ISO 20022?: DU01 is Duplicate Message ID in the ExternalStatusReason1Code code set: Message Identification is not unique.
Where does DU01 appear in a message?: For example in pacs.002, element TxInfAndSts/StsRsnInf/Rsn/Cd.

All ExternalStatusReason1Code codes · ISO 20022 code sets · pacs.002 reject reasons explained

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