Receipt and Invoice Compliance

SIGN PT supports the issuance of Portuguese fiscally relevant documents (e.g. invoices, receipts, and correction documents such as credit notes) using Autoridade Tributária e Aduaneira (AT)-certified invoicing logic (Portaria 363/2010). Documents are signed and hash-chained at issuance time, assigned to a document series, and receive a strictly sequential number — sequence numbers are not pre-assigned.

For each document, SIGN PT provides the data needed for the mandatory elements:

Element	What it is
AT-certified software	Documents must be issued using AT-certified invoicing software. The customer-facing document must include the certification mention with the AT certificate number (e.g. “Processado por programa certificado n.º …”).
ATCUD	Composed as validation_code-sequential_number. The validation code is obtained during series registration.
QR code	The QR code content, ready to embed in the printed or PDF document.
Hash excerpt	The 4-character hash excerpt required for the document footer.
SAF-T (PT) data	Relevant data for reporting and export (manual export).

The POS or ERP is responsible for rendering or printing all mandatory visual elements on the final document (paper or PDF) using the values returned by SIGN PT, including correct placement and formatting per AT rules. See Printed document layout for the concrete rendering specification.

Additional compliance points to consider

Rule	Detail
Series registration	Each document type must be issued within a registered and validated series before issuance. The fiskaly SIGN PT API will do this for you. The WSE permission is required for series communication though — see Credentials.
Mandatory printed elements	Every fiscally relevant document must carry the ATCUD, QR code, software certification mention with certificate number, and the hash excerpt. See Printed document layout for format and placement rules.
No post-issuance edits	Once issued, documents cannot be changed. Use a correction document (credit or debit note) for corrections, and a status change to A (Anulado) for cancellations — not deletions.
VAT configuration	VAT rates depend on the fiscal region (mainland, Azores, Madeira). If VAT is exempt or zero-rated, the relevant exemption code and reason must be provided and displayed where required.
Reporting and export	Invoicing data is submitted via monthly SAF-T (PT) (due by the 5th for web service submission, or the 8th for manual upload) and/or in real time via AT Web Services if WFA/WDT permissions were granted — see Credentials. SAF-T (PT) export must be supported regardless of reporting mode.
Retention and archiving	Fiscal data must be retained for 10 years and be retrievable for audit purposes.
PDF QES requirement	From 1 January 2027, PDF invoices used as electronic invoices must carry a qualified electronic signature (QES) under Article 80(3) of the 2026 State Budget. This is independent of the ATCUD/QR code requirements.

Obligation to issue invoices and receipts

Issuing a compliant invoice or receipt in Portugal is handled through the SIGN PT API. For each fiscally relevant document, the API ensures the document is:

1. Created and signed

   The document is created and signed in a compliant way using AT-certified invoicing logic.

2. Sequentially numbered

   The document is numbered within a registered and validated series with a strictly sequential number.

3. Enriched with compliance data

   The document is enriched with the mandatory ATCUD and QR code data, plus the hash excerpt required for printing.

The customer-facing document delivered at the time of purchase can be:

Paper

Printed at the point of sale.

Electronic

A PDF sent by email or made available via a portal, provided all applicable legal requirements are met. From 1 January 2027, PDFs used as electronic invoices must additionally carry a QES (see PDF QES requirement above).

📘Note

Testing is not supported in the LIVE environment, as all data is treated as production and may be transmitted or used for compliance reporting. Use the designated TEST environment for integration testing.