ACH Notification of Change code
C05 NOC code: Incorrect Transaction Code
An RDFI sends C05 instead of returning an entry it could post but that carried outdated or wrong information. Corrected data: Correct Transaction Code in positions 1–2.
What C05 means
C05 is the change code Incorrect Transaction Code
. The entry it answers was posted (or, for a prenotification, accepted); the NOC tells the Originator what to correct before the next one.
- The transaction code is for the wrong kind of account — a checking code (22, 27) sent to a savings account, which takes 32 or 37, or the other way round.
What to update, and by when
Replace the stored Transaction Code, which usually means recording the account as checking or savings correctly.
The Rules give the Originator six banking days from receiving the NOC information, or until its next entry to the account, whichever is later. NOCs carry no money: the entry they answer settled normally.
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.
Worked example
For an entry that settled on Wednesday, November 25, 2026, the day before Thanksgiving: the RDFI must transmit the NOC by Monday, November 30, 2026.
How C05 appears 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 C05 NOC |
|---|---|---|
| 1 | Record Type Code | 7 (addenda) |
| 2–3 | Addenda Type Code | 98 (Notification of Change) |
| 4–6 | Change Code | C05 |
| 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 Transaction Code in positions 1–2 |
| 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 C05 from code or an AI agent
curl -s 'https://payopskit.com/api/v1/codes/C05?set=ach-noc'{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/call",
"params": {
"name": "lookup_payment_code",
"arguments": {
"code": "C05",
"set": "ach-noc"
}
}
}{
"code": "C05",
"set": "ach-noc",
"found": true,
"matches": [
{
"set": "ach-noc",
"code": "C05",
"name": "Incorrect Transaction Code",
"description": "Notification of Change. Corrected data: Correct Transaction Code in positions 1–2.",
"details": {
"refused": false,
"retired": false,
"correctedData": "Correct Transaction Code in positions 1–2",
"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": 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.
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.