ACH return reason code

R31 return code: Permissible Return Entry

A CCD or CTX entry returned after the normal deadline, with the ODFI’s agreement.

What R31 means

R31 is the return reason code Permissible Return Entry. A CCD or CTX entry returned after the normal deadline, with the ODFI’s agreement.

CCD and CTX entries only.

It is sent by the RDFI as a return entry: the original entry goes back to the ODFI with an addenda record carrying R31, and the ODFI passes the return on to the Originator.

Typical causes

The RDFI returned a CCD or CTX entry after the normal return deadline, and the ODFI agreed to accept it.

Return timeframe

No fixed timeframe: the RDFI may return a CCD or CTX entry after the normal deadline only if the ODFI agrees.

What the Originator can do next

Nothing to correct in the entry: the ODFI accepted the late return. Settle the dispute with the Receiver directly.

How R31 appears in a NACHA file

A return is the original entry detail record (type 6) sent back with a return transaction code — 21 or 26 for a checking account, 31 or 36 for savings (21 and 31 return a credit, 26 and 36 a debit) — the original amount, and an addenda record of type 99 that carries the reason. The batch keeps the original entry’s SEC code.

Return addenda record (type 99) with R31
Positions	Field	In an R31 return
1	Record Type Code	7 (addenda)
2–3	Addenda Type Code	99 (return)
4–6	Return Reason Code	`R31`
7–21	Original Entry Trace Number	Trace number of the entry being returned
22–27	Date of Death	YYMMDD for R14 and R15; blank otherwise
28–35	Original Receiving DFI Identification	First 8 digits of the original entry’s RDFI routing number
36–79	Addenda Information	Free text from the RDFI
80–94	Trace Number	The return entry’s own trace number

To read a return file record by record, open the file in NACHA Navigator, a free sister site that parses NACHA files in your browser without uploading them.

Look up R31 from code or an AI agent

The code table on this page is the one behind the REST API and the MCP server, so a script or an AI agent gets the same answer as JSON. No key and no account.

REST · GET · no key

curl -s 'https://payopskit.com/api/v1/codes/R31?set=ach-return'

MCP · tools/call · lookup_payment_code

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "lookup_payment_code",
    "arguments": {
      "code": "R31",
      "set": "ach-return"
    }
  }
}

Response (JSON)

{
  "code": "R31",
  "set": "ach-return",
  "found": true,
  "matches": [
    {
      "set": "ach-return",
      "code": "R31",
      "name": "Permissible Return Entry",
      "description": "A CCD or CTX entry returned after the normal deadline, with the ODFI’s agreement.",
      "details": {
        "category": "return",
        "timeframe": "No fixed timeframe: the RDFI may return a CCD or CTX entry after the normal deadline only if the ODFI agrees",
        "timeframeKind": "agreement",
        "timeframeDays": null,
        "timeframeFrom": null,
        "account": "corporate",
        "accountNote": "CCD and CTX entries only.",
        "writtenStatement": false,
        "initiatedBy": "RDFI",
        "note": "CCD and CTX only",
        "effectiveFrom": null,
        "upcomingChange": null,
        "caveat": null
      }
    }
  ]
}

The MCP server is at /mcp (Streamable HTTP, no key); the API and MCP docs show how to connect Claude, Cursor or VS Code.

The deadline for a settlement date: GET /api/v1/ach/return-deadline?settlement_date=2026-11-25&code=R31 or the MCP tool ach_return_deadline.

Source: Nacha Operating Rules, Appendix Four (Return Entries). The code’s title is the Rules’ own; the rest is this site’s plain-language summary. It is informational and not a substitute for the Rules, your ACH Operator’s schedule or your ODFI agreement.