Free ACH reversal file generator
Reverse an ACH file or its entries
Open the original NACHA file, pick the entries to undo — one, a batch or the whole file — and download a reversal file with the transaction codes flipped, REVERSAL as the company entry description and the totals recalculated. It all happens in your browser.
- Transaction codes flipped
- Five-banking-day deadline checked
- Receiver notices drafted
Drop the original NACHA file
The file that carried the erroneous entries: .ach or .txt
No file at hand? Try the demo: payroll, membership and vendor payments dated the previous banking day, built in your browser for today.
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How it works
From the original file to its reversal.
The reversal is built from the file you sent, so every entry keeps its Receiver, account and amount. Nothing is typed in again.
Step 1
Open the original file
Drop the NACHA file that carried the erroneous entries, or try the demo. It opens in the NACHA Viewer’s Generate Reversal tab and stays in this browser tab.
Step 2
Select entries
Pick the erroneous entries, a whole batch at once, or the entire file. Entries that can’t be reversed, such as prenotes and returns, are marked with the reason.
Step 3
Reason and dates
Say why the entries are being reversed and choose the effective date. The tool shows the deadline: five banking days after the original entries settled.
Step 4
Review and generate
The tool builds the file, checks it against the rules and the original, and lets you download it only once it passes NACHA validation, with a notice to send each Receiver.
The rules
What a reversal may and may not do
The Nacha Operating Rules allow a reversal only to correct an erroneous entry, in a fixed format, within five banking days. These are the rules the tool applies, in plain terms.
Last updated
When you can reverse an entry
Only an erroneous entry can be reversed. The reason is not written in the file, since a reversing entry has no field for it, but it goes into the notice to the Receiver.
| Reason | What happened | Whole file | Afterwards |
|---|---|---|---|
| Duplicate entry | The entry (or the whole file) repeats one the Originator already sent. | Yes | — |
| Wrong Receiver / account | The entry paid or debited a different Receiver or account than the Originator intended. | Yes | Send the payment to the intended Receiver as a separate, new entry. |
| Wrong amount | The entry was for a different dollar amount than the Originator intended. | Yes | Reverse the full amount, then send a new entry for the correct amount. |
| Wrong date (debit earlier than intended) | A debit carried an Effective Entry Date earlier than the Originator intended. | Yes | If the payment is still due, send a new debit with the intended date. |
| Wrong date (credit later than intended) | A credit carried an Effective Entry Date later than the Originator intended. | Yes | If the payment is still owed, send a new credit with the intended date. |
| PPD credit already paid by a check at separation | A PPD credit of employment-related funds that were already paid in full by a check delivered to the Receiver at or before separation from employment, where the credit was sent before the check was delivered. | No, entries only | — |
When you can’t
None of these makes an entry erroneous, so none of them is a reason to reverse it.
| Situation | Why it isn’t a reason | What to do instead |
|---|---|---|
| Insufficient funds | A debit that bounced, or a credit the Originator cannot cover, is not an erroneous entry. | An unpaid debit comes back as a return from the Receiver’s bank (R01 or R09); a credit must be funded. |
| The Originator or a Third-Party Sender did not fund the original credit | The Rules name a funding failure as an improper reason for a reversal. | Arrange funding with your ODFI. |
| A dispute with the Receiver | A disagreement about goods, services or an invoice is not an error in the entry. | Resolve it with the Receiver; any new debit needs the Receiver’s authorization. |
| A change of mind | An entry sent as intended cannot be pulled back because plans changed. | Ask the Receiver to return the funds, or ask your ODFI to request a return (R06), which the Receiver’s bank may decline. |
| The Receiver says a debit was unauthorized | Unauthorized debits are handled by the Receiver’s bank through returns (R05, R07, R10 or R11 for a consumer account; R29 for a business account). | Do not reverse; refund the Receiver with a separate credit if you agree. |
| More than five banking days after settlement | A reversal made available to the Receiver’s bank after the window is improper; that bank may return it (R11 or R17). | Ask your ODFI to request a return of the erroneous entry (R06). |
| Reversing only part of the amount | A reversing entry carries exactly the amount of the erroneous entry. | Reverse the full amount, then send a new entry for the correct amount. |
What a reversing entry looks like
- Company Entry Description:
REVERSAL, in place of the original batch’s description. - Company Identification and SEC code: unchanged from the original batch. The Company Name must still identify the same Originator; the tool copies it as it was.
- Amount: the full amount of the erroneous entry. To correct an amount, reverse the whole entry and send a new one for the right amount.
- Transaction Code: the same kind of account, the other direction (table below).
- Service Class Code: worked out again for the reversal batch: 220 when it holds only credits, 225 when it holds only debits, 200 when it holds both.
- Trace numbers: new ones, starting with the ODFI routing number from the batch header.
Transaction codes and their reversals
| Original | Account | Original moves | Reversal |
|---|---|---|---|
| 22 | Checking | Credit | 27 |
| 27 | Checking | Debit | 22 |
| 32 | Savings | Credit | 37 |
| 37 | Savings | Debit | 32 |
| 42 | General ledger | Credit | 47 |
| 47 | General ledger | Debit | 42 |
| 52 | Loan | Credit | 55 |
| 55 | Loan | Debit | 52 |
Transaction Code 55, a loan debit, exists only to reverse a loan credit (52). Prenotes, zero-dollar entries, notifications of change and ADV records move no money, so there is nothing to reverse. A return is the Receiver’s bank sending an entry back, not an entry the Originator can reverse; an ODFI answers a faulty return by dishonoring it (R61, R62, R67–R70).
A reversal normally moves money against its SEC code’s usual direction. Under ARC, BOC, POP, RCK, TEL and XCK, which carry only debits, a reversing credit keeps the SEC code, and so does a reversing debit under CIE, which carries only credits (return reasons R36 and R35 make these exceptions). For other one-way SEC codes, such as TRC and TRX, ask your bank how to correct the entry. The tool doesn’t reverse IAT entries yet.
The five-banking-day window
A reversing entry must be made available to the Receiver’s bank within five banking days after the settlement date of the erroneous entry. Banking days are Monday to Friday, except Federal Reserve holidays. A debit reversal may not carry an Effective Entry Date earlier than the credit it reverses.
The tool counts the deadline from the original batch’s settlement date: the one an ACH Operator wrote in the batch header, the one you enter from your bank statement, or else the Effective Entry Date. For date math outside the tool, PayOps Kit’s ACH dates tool (opens in a new tab) works out return, NOC and reversal deadlines.
When the window has closed, a reversal is no longer allowed. Ask your bank (the ODFI) to request a return of the erroneous entry instead, with return reason R06; the Receiver’s bank may decline.
Telling the Receiver
The Originator must make a reasonable attempt to tell each Receiver about the reversal and its reason no later than the reversal’s settlement date. For a PPD credit already paid by a check at separation, the Receiver must be told at the time the check is delivered. Before it generates a file, the tool asks you to confirm the notice, and it drafts one for each Receiver, with the account number masked.
Reversing a whole file
A reversing file undoes every entry of a file sent in error. Unless the erroneous file was a duplicate, it goes with a correcting file that carries the right entries; the NACHA Generator can build one. Send the reversing file, and any correcting file, within 24 hours of discovering the error, as well as within the five-banking-day window. A PPD credit already paid by check at separation can be reversed only as a single entry, not with a whole file.
If a reversal is improper
A reversal sent for a reason the Rules don’t allow, or after the window, is improper. The Receiver’s bank can return it with return reason R11 for a consumer account, within 60 days once the Receiver signs a written statement, or with R17 within two banking days.
A reversal also isn’t guaranteed to post: the Receiver’s bank doesn’t have to accept a reversing entry, and a reversing debit can be returned, for example for insufficient funds.
Sources
These rules follow the Nacha Operating Rules on reversing files and reversing entries, as summarized in Nacha’s public page on the 2021 reversals rule, and the return reason codes in Appendix Four. Your bank’s agreement may add requirements of its own.
NACHA Navigator is independent and not affiliated with or endorsed by Nacha. This page is for information only; it is not legal or compliance advice.