Retired ACH Notification of Change code
C11 NOC code (retired): Incorrect Company Identification
C11 is a retired change code: RDFIs no longer send it. Removed from the Nacha Rules in 2003, with C10–C12, because RDFIs seldom used them.
What C11 meant
C11 was the change code Incorrect Company Identification
. Like any NOC, it answered an entry that had posted and told the Originator what to correct before the next one.
- Until 2003 an RDFI could send C11 when the Company Identification in the batch header was wrong.
- Nacha removed C10, C11 and C12 that year because RDFIs seldom used them.
If you see C11 today
Nothing to correct because of a C11 today. The Company Identification is set up with your ODFI; if returns such as R21 point to it, check it with the ODFI.
The change codes in use today are C01, C02, C03, C05, C06, C07, C08, C09, C13, C14; a file or code table that still lists C11 predates its removal.
How C11 appeared in a NACHA file
A NOC is a zero-dollar entry in a batch with SEC code COR. Its entry detail record carries a return-type transaction code (21, 26, 31 or 36) and one addenda record of type 98:
| Positions | Field | In a C11 NOC |
|---|---|---|
| 1 | Record Type Code | 7 (addenda) |
| 2–3 | Addenda Type Code | 98 (Notification of Change) |
| 4–6 | Change Code | C11 |
| 7–21 | Original Entry Trace Number | Trace number of the entry being corrected |
| 22–27 | Reserved | Blank |
| 28–35 | Original Receiving DFI Identification | First 8 digits of the original entry’s RDFI routing number |
| 36–64 | Corrected Data | Correct Company Identification in positions 1–10 |
| 65–79 | Reserved | Blank |
| 80–94 | Trace Number | The NOC entry’s own trace number |
To read a NOC 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 C11 from code or an AI agent
curl -s 'https://payopskit.com/api/v1/codes/C11?set=ach-noc'{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/call",
"params": {
"name": "lookup_payment_code",
"arguments": {
"code": "C11",
"set": "ach-noc"
}
}
}{
"code": "C11",
"set": "ach-noc",
"found": true,
"matches": [
{
"set": "ach-noc",
"code": "C11",
"name": "Incorrect Company Identification",
"description": "Retired Notification of Change code: RDFIs no longer send it. Removed from the Nacha Rules in 2003, with C10–C12, because RDFIs seldom used them. Corrected data was: Correct Company Identification in positions 1–10.",
"details": {
"refused": false,
"retired": true,
"correctedData": "Correct Company Identification in positions 1–10",
"timeframe": "The RDFI transmits the NOC within 2 banking days of the settlement date of the original entry; the Originator makes the change within 6 banking days of receiving the NOC information or before its next entry, whichever is later",
"timeframeKind": "banking-days",
"timeframeDays": 2,
"caveat": "Retired. Removed from the Nacha Rules in 2003, with C10–C12, because RDFIs seldom used them. An RDFI should not send it today."
}
}
]
}The MCP server is at /mcp (Streamable HTTP, no key); the API and MCP docs show how to connect Claude, Cursor or VS Code.
Source: Nacha Operating Rules, Appendix Five (Notification of Change). The code’s title is the Rules’ own; the rest is this site’s plain-language summary, informational and not a substitute for the Rules or your ODFI agreement.