R36 return code: Return of Improper Credit Entry

R36 is the return reason code Return of Improper Credit Entry. A credit sent under an SEC code that allows only debits (ARC, BOC, POP, RCK, TEL or XCK).

It is sent by the RDFI as a return entry: the original entry goes back to the ODFI with an addenda record carrying R36, and the ODFI passes the return on to the Originator.

• A credit was sent under an SEC code that allows only debits: ARC, BOC, POP, RCK, TEL or XCK.

Available to the ODFI by opening of business on the 2nd banking day after the settlement date of the original entry.

Banking days are the Federal Reserve’s business days: weekends and Fed holidays don’t count, so a holiday in the window pushes the deadline out by a day.

• Send the credit under a code that allows credits — PPD to a consumer account, CCD to a business account.

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.

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.

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.

curl -s 'https://payopskit.com/api/v1/codes/R36?set=ach-return'

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "lookup_payment_code",
    "arguments": {
      "code": "R36",
      "set": "ach-return"
    }
  }
}

{
  "code": "R36",
  "set": "ach-return",
  "found": true,
  "matches": [
    {
      "set": "ach-return",
      "code": "R36",
      "name": "Return of Improper Credit Entry",
      "description": "A credit sent under an SEC code that allows only debits (ARC, BOC, POP, RCK, TEL or XCK).",
      "details": {
        "category": "return",
        "timeframe": "Available to the ODFI by opening of business on the 2nd banking day after the settlement date of the original entry",
        "timeframeKind": "banking-days",
        "timeframeDays": 2,
        "timeframeFrom": "original-settlement",
        "account": "any",
        "accountNote": null,
        "writtenStatement": false,
        "initiatedBy": "RDFI",
        "note": null,
        "effectiveFrom": null,
        "upcomingChange": null,
        "caveat": null
      }
    }
  ]
}

The deadline for a settlement date: GET /api/v1/ach/return-deadline?settlement_date=2026-11-25&code=R36 or the MCP tool ach_return_deadline.

• R35Return of Improper Debit Entry

SEC codes involved: ARC, BOC, POP, RCK, TEL, XCK.

All ACH return codes, R01 to R85