How to replace a DMR already filed

What is it for?

When you correct a payslip whose payment was already included in a filed DMR, the month must be declared again. This return is called a Replacement return. fiscaldoo prepares it with all the paid payslips of the month, shows what changed from the original and only lets it go ahead if there is a change. fiscaldoo does not file anything with the AT: the file is filed on the Portal das Finanças, outside the product.

When to use it?

• When a payslip of a month whose DMR has already been filed is corrected (see correct a payslip already processed).
• When you find that the filed DMR has wrong amounts and you have already corrected the payslips.

Where to find it?

Payroll › Declare › Monthly remuneration statement (DMR)

Before you start

• Payroll Processor profile, which was used for the steps in this article. Filing and recording the AT's response is done with the Declaration submitter (see DMR).
• The month's original DMR exists and is already Submitted or Accepted. In the demo, the August 2026 one is Submitted.
• The payslip has been corrected: there is a corrective payslip, opened from Payroll › Process › Processing corrections. If the month has already been declared, fiscaldoo only lets you validate the corrective payslip once the replacement return exists, so it is generated from the correction's Replacement DMR line (see How to correct a payroll run). The full step-by-step is in DMR, “Correct a DMR already filed”; this article covers what the screen does and refuses.

How to use it

1. In Payroll › Declare › Monthly remuneration statement (DMR), click New.
2. Fill in Tax office (Quadro 1), Year (Quadro 3) and Month (Quadro 3) of the return you want to replace (in the example, 2026, August).
3. In Kind of declaration (Quadro 6), choose Replacement return and click Generate.
4. At the top, the Differences against the declaration it replaces block appears: Replaces shows the original return (in the example, DMR 2026-08 (1.ª declaração)) and, below it, Difference: income, Difference: IRS withheld, Difference: contributions and Difference: union dues. The Titulars (Quadro 5) list contains all the employees of the month (8 lines, income of €11,076.67 and IRS of €832.00 in the example), as in the original.
5. Check the differences against what you corrected. If they are right, click Validate, then Generate delivery file, Download delivery file and file it on the Portal das Finanças.

Expected result

• A return for the same year and month, of the Replacement return type, next to the original, in the Generated state and then Validated.
• Non-zero differences in at least one of the four lines. If they are all 0.00, it can only be validated after the Payroll Administrator clicks Confirm without differences (see “Common problems”).

Important notes

• The replacement declares everything, not only the difference. It includes all the paid payslips of the month, like the original; the difference is for information only.
• The original stays as it was. After you generate the replacement, the original DMR does not change state.
• Deadline and consequences. The deadline, the date of the event and the choice between a replacement and a late return depend on the case. Pending validation by a certified accountant: deadline for filing the replacement, when to use the return with the date of the event, and settling any fine.
• Delivery file. The screen warns that the file follows the AT format, but “it was not yet checked with the validator of the Portal das Finanças”. Check it on the portal before filing.
• “First or replacement” field. On screen the field is called Kind of declaration (Quadro 6) and has the options 1st declaration, Replacement return and the return with the date of the event. Pending validation by a certified accountant: what Quadro 6 should contain in each case.

Common problems

“Invalid Operation: The replacement … has no difference from …”

• Symptom: when you click Validate, the screen says “A substituição “DMR 2026-08 (Declaração de substituição)” não tem diferença face a “DMR 2026-08 (1.ª declaração)”. O que aconteceu: uma substituição que declara os mesmos valores não substitui nada. Como corrigir: …” (The replacement “DMR 2026-08 (Replacement return)” has no difference from “DMR 2026-08 (1st declaration)”. What happened: a replacement that declares the same amounts replaces nothing. How to fix it: check that the corrective payslip is validated and generate the lines again or, if that really is the intention, ask the payroll administrator to open this return and click “Confirm without differences” in the top bar (only that profile sees the button) and validate again.) The banner at the top says “This declaration has no difference against the one it replaces”.
• Cause: no payslip of the month has changed since the original (in the test, August 2026, with no corrective payslip).
• What to do: Go back to the correction in Payroll › Process › Processing corrections, check that the corrective payslip is computed and generate the Replacement DMR line from it; then click Generate again. If a replacement without differences really is the intention, the Payroll Administrator opens the return and clicks Confirm without differences, in the top bar: then Validate makes it Validated.

I no longer want this replacement

• Symptom: you generated a replacement by mistake.
• What to do: click Without effect and Confirm in the window “The declaration stays in the list for the record and can no longer be validated or submitted. A new one for the same month can then be created. Continue?”. The return moves to the Without effect state, stays in the list and no longer has buttons.

“A return of this type already exists …”

• Symptom: when you click Generate, the screen says “Já existe uma declaração deste tipo para (empresa) em 08/2026 …” (A return of this type already exists for (company) in 08/2026 …).
• Cause: each payment month has only one live return of each type.
• What to do: open the existing one; if it has not been submitted yet and you no longer want it, click Without effect on it and create another.