How to issue a credit note

What is it for?

An issued invoice can no longer be changed: it has a number, ATCUD and signature. When the customer returns goods, when the price or quantity was wrong, or when you give a discount after invoicing, the correction is made with a credit note.

The credit note is a new certified document, with its own series, number and ATCUD, which states the invoice it corrects and the reason. It can credit the whole invoice or just part of it. The VAT regularisation details you fill in here go into the periodic VAT return (box 40 and its annex).

When to use it?

• The customer returned all or part of the goods.
• The invoice went out with a wrong price or quantity.
• You gave a discount or a rebate after issuing the invoice.
• The operation was cancelled after it was invoiced.

Two cases have their own path:

• The customer's details are wrong (name, address, tax number (NIF)): see I cannot change an invoice already issued.
• The invoice was issued by mistake and the operation did not happen: see How to cancel an invoice or another certified document.

Where to find it?

Billing › Invoice › Customer invoices › open the invoice › Credit Note

Issued credit notes are in Billing › Invoice › Customer credit notes.

Before you start

• Your profile is Administrative or Accountant.
• The invoice is in the Posted state.
• You know what happened (return, error, discount) and when: the date that counts for the VAT regularisation deadline depends on the reason (see step 5 and “Deadline to regularise the VAT”).
• You have, or will have, evidence that the customer was informed of the correction (for example, the email in which you send them the note). fiscaldoo asks you to state it.

How to use it

1. Open Billing › Invoice › Customer invoices and open the invoice you want to correct.
2. Click Credit Note.
3. In the Create credit note window, in Reason, choose what happened: Return of goods, Price error, Quantity or item error, Cancellation of the operation, Discount or rebate granted or Other (describe). With Other (describe), write the reason in Describe the reason.
4. In VAT regularization reason, choose the legal basis. The window itself says: “Return, cancellation or discount on a sale: art. 78, para. 2”, which in the list is called Cancellation or reduction of the operation (invalidity, termination, return of goods, discounts). For a price or quantity error, see “Which VAT reason to choose” below.
5. In Regularization reference date, enter the date the VAT reason asks for. Below the field, the window says which one:
   • Cancellation or reduction of the operation (…): “The reference date is: Date of the circumstances that cancelled the operation or reduced its value”, that is, the day of the return, discount or cancellation.
   • Correction of material or calculation errors, in favour of the taxable person: “The reference date is: Date the right to deduct arose (art. 22.º n.º 1) or the date of the record”.
   • Inaccurate invoice, VAT charged too much (optional rectification): the window does not show that sentence or require the date. Leave the field empty: fiscaldoo counts the deadline from the date of the invoice you are correcting.
6. In Regularization proof, say how you show that the customer was informed of the correction, for example “Email of 28/10/2026”.
7. Leave Journal and Reversal date as they are: the journal is the invoice's and the date is today, which becomes the credit note date.
8. Click Create credit note. The draft note opens, with all the invoice lines.
9. If you are only crediting part of it, change the quantity or price on the lines and delete the lines you do not want to credit. Do not change the customer or the VAT rate.
10. Click Confirm. The credit note gets the series number, the ATCUD and the signature.

Example. Invoice FT D26/44 has 10 office supply kits at €85.00 + 23% VAT, total €1,045.50. The customer returns 2 kits on 28/10/2026. On the draft, the quantity goes from 10 to 2 and the credit note comes to €170.00 + €39.10 VAT = €209.10. The invoice becomes Partially paid, with €836.40 outstanding. It is the same example as in the video.

Expected result

• The credit note is Posted, with the number from the credit note series (NC D26/12 in the example) and the ATCUD (DEMONC2026-12).
• The note shows the Rectified document (the invoice), the Reason for the rectification and the VAT regularisation details. The Original invoice button opens the invoice.
• The note is offset against the invoice. If you credited part of it, the invoice shows Partially paid and the amount due goes down by the same amount. If you credited the whole invoice, the invoice becomes Reversed (not “Paid”: no payment was received).

Demo video

No telemóvel, rode-o para a horizontal e veja o vídeo em ecrã inteiro: o texto do ecrã fica legível.

Issue a credit note for a return · 34 s · sem som, com legendas · legendas (WebVTT)

Transcrição

Important notes

Deadline to regularise the VAT

The deadline depends on the VAT regularization reason you choose, and so does the date it counts from (step 5):

• Cancellation or reduction of the operation (…) (VAT Code (CIVA), art. 78, para. 2): until the end of the tax period following the one of the date of the circumstances that cancelled or reduced the operation. Under a monthly scheme, a June return is regularised by 31 July.
• Inaccurate invoice, VAT charged too much (optional rectification): two years from the date of the invoice it corrects.
• Correction of material or calculation errors, in favour of the taxable person: two years from the date the right to deduct arose or the date of the record.

Today fiscaldoo lets you confirm a note outside the deadline and records the warning in the note's message history, for example: “Document … regularizes VAT in favour of the taxable person on 28/10/2026, after the legal deadline (31/07/2026, CIVA art. 78.º: CIVA art. 78.º n.º 2). Check with the accountant whether the deduction is still possible.” If you see this warning, talk to the certified accountant before counting on recovering the VAT. Pending validation by a certified accountant: deadlines and counting dates under art. 78.

Which VAT reason to choose

The VAT reason decides the box and the deadline

For a sales credit note, the list offers six reasons: Cancellation or reduction of the operation (…), Inaccurate invoice, VAT charged too much (optional rectification), Correction of material or calculation errors, in favour of the taxable person, Deduction of VAT on credits considered uncollectible (…), Deduction of VAT on other credits (…) and e-Taxfree (…). All of them take the regularisation to box 40, but each has its own deadline and conditions. Return, cancellation and discount are Cancellation or reduction of the operation, as the window says. For a price or quantity error, the choice between that reason, Inaccurate invoice, VAT charged too much and Correction of material or calculation errors depends on the case: decide it with the certified accountant. The last three reasons (uncollectible credits, other credits, e-Taxfree) have their own rules and are not for correcting an invoice. Pending validation by a certified accountant: VAT reason by type of error.

Regularisation proof

To recover the VAT, the company must have proof that the customer was informed of the correction or was refunded (CIVA, art. 78, para. 5). Regularization proof records where that proof is; the proof must exist and be kept. Pending validation by a certified accountant.

Other notes

• A posted credit note can no longer be changed either. If you credited too much, the screen itself shows the way: issue a debit note.
• The reason goes into the SAF-T and to the AT. With Other (describe), the text is cut at 50 characters (in the demo, a 62-character reason kept the first 50): keep it short.
• Create credit note and a new invoice issues the credit note already posted, for the invoice total, and opens a new draft invoice for the same customer with the same lines: correct it and click Confirm. In the demo, with the Administrative profile, FT D26/31 for €123.00 gave NC D26/2, posted, and a draft invoice for €123.00.

Common problems

I cannot click Create credit note

• Symptom: “Some required fields are empty. Fill in the fields marked in red to be able to save.” appears.
• Cause: Reason and VAT regularization reason are required; Regularization reference date and Regularization proof too, depending on the VAT reason (and Describe the reason, with Other (describe)).
• What to do: fill in the fields in red and click again.

The note is refused for crediting more than was invoiced

• Symptom: when you click Confirm: “Credit note … would credit line "Material de escritório (kit)" of document "FT D26/44" beyond what was invoiced: already credited 2.0 units / €170.00, this note 9.0 units / €765.00, invoiced 10.0 units / €850.00. Reduce the quantity or the value of the line.”
• Cause: adding up the credit notes already issued for that invoice, the new note would exceed the invoiced amount.
• What to do: reduce the line's quantity or price to what is left to credit and click Confirm again.

The credit note does not get a number on confirmation

• Symptom: when you click Confirm, the “Cannot confirm yet” window opens: “Journal “…” has no series of the type “[NC] Nota de crédito” ready for 2026. The active series (…) are of other types and cannot number this document. … Create and activate a series of type “[NC] Nota de crédito” for 2026: the button below opens the form already filled in.”
• Cause: the invoice's journal has no active credit note series for the note's year. The note stays as a draft, without a number.
• What to do: the window has the Create the missing series button, which opens the series form already filled in, but creating and communicating a series is the Certified accountant's job. If you do not have that profile, click Close and ask them to do it: How to create a series and communicate it to the AT. With the series active, open the draft and click Confirm again.