ACH return reason code
R39 return code: Improper Source Document/Source Document Presented for Payment
The check behind an ARC, BOC or POP debit was not eligible for conversion, or was already paid.
What R39 means
R39 is the return reason code Improper Source Document/Source Document Presented for Payment
. The check behind an ARC, BOC or POP debit was not eligible for conversion, or was already paid.
ARC, BOC and POP entries.
It is sent by the RDFI as a return entry: the original entry goes back to the ODFI with an addenda record carrying R39, and the ODFI passes the return on to the Originator.
Typical causes
- The check behind an ARC, BOC or POP debit was not eligible for conversion to ACH.
- Or it had already been presented for payment.
Return timeframe
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.
Worked example
For an entry that settled on Wednesday, November 25, 2026, the day before Thanksgiving: must be available to the ODFI by opening of business on Monday, November 30, 2026.
What the Originator can do next
- Check that a check is an eligible item under the Rules before converting it.
How R39 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.
| Positions | Field | In an R39 return |
|---|---|---|
| 1 | Record Type Code | 7 (addenda) |
| 2–3 | Addenda Type Code | 99 (return) |
| 4–6 | Return Reason Code | R39 |
| 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 R39 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.
curl -s 'https://payopskit.com/api/v1/codes/R39?set=ach-return'{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/call",
"params": {
"name": "lookup_payment_code",
"arguments": {
"code": "R39",
"set": "ach-return"
}
}
}{
"code": "R39",
"set": "ach-return",
"found": true,
"matches": [
{
"set": "ach-return",
"code": "R39",
"name": "Improper Source Document/Source Document Presented for Payment",
"description": "The check behind an ARC, BOC or POP debit was not eligible for conversion, or was already paid.",
"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": "ARC, BOC and POP entries.",
"writtenStatement": false,
"initiatedBy": "RDFI",
"note": null,
"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=R39 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.