Portugal's fiscalization compliance, from a single API.

Yes. Portugal requires all invoicing and POS software to be certified by the Portuguese Tax Authority (AT). Certified software guarantees that invoices contain the mandatory ATCUD identifier, a QR code, and a cryptographic hash chain that ensures document integrity. Using non-certified software can result in fines and document rejection during audits. SIGN PT operates through AT-certified software, so your integration is compliant from day one — no separate certification process needed on your end.

ATCUD (Autoridade Tributária Código Único do Documento) is Portugal's mandatory unique document identifier. It has been required on all invoices and fiscally relevant documents since January 1, 2023. It is composed of a series of validation codes assigned by the AT, combined with the document's sequential number within that series. Every invoice must display the ATCUD prominently on both printed and digital versions. SIGN PT automates the entire ATCUD workflow: series registration with the AT, validation code retrieval, and code generation for every invoice issued.

A Qualified Electronic Signature (QES) will become mandatory for all PDF invoices in Portugal from January 1, 2027. This requirement was confirmed by Portugal's 2026 State Budget, approved by the National Assembly on November 27, 2025. Until December 31, 2026, PDF invoices issued by AT-certified software with ATCUD and QR code remain fully valid without a digital signature. SIGN PT is already being built to support QES natively — meaning your integration will not require a full overhaul when the 2027 deadline arrives.

SAF-T (PT) — Standard Audit File for Tax — is a standardized XML reporting format required by the AT. All VAT-registered businesses in Portugal must submit a monthly SAF-T Billing file containing invoice and transaction data. From 2028, a full SAF-T Accounting report covering fiscal year 2027 will also become mandatory. SIGN PT generates and submits the monthly SAF-T Billing file automatically on your behalf, keeping your clients fully compliant without manual intervention.

No. Our Portugal fiscalization API, fiskaly SIGN PT, covers all three requirements under a single API. Just one integration, and you get full Portuguese fiscal compliance.

Yes. SIGN PT supports B2B invoices (business-to-business invoices with full ATCUD, QR, and hash-chain compliance), and B2C invoices (consumer invoices meeting AT certification requirements). This makes fiskaly SIGN PT suitable for POS, ERP, and SaaS platforms in Portugal.

Non-compliance with Portugal's invoicing requirements can result in financial penalties, rejection of documents during tax audits, and the obligation to reissue documents under AT supervision. The AT may also audit and revoke the certified software status of non-conforming solutions. Working with a certified and continuously maintained solution like SIGN PT eliminates this exposure — ensuring every invoice is correct, traceable, and audit-ready at all times.

fiskaly SIGN PT is a REST API. You send your invoice data — customer details, line items, VAT rates, and totals. The API handles: ATCUD generation (including series registration and validation code retrieval from the AT), QR code creation, cryptographic hash-chain signing, PDF generation with all mandatory elements, and monthly SAF-T submission. The final, fully compliant invoice document is returned to your system. No hardware required, no local software to install or maintain.

No. One of the core advantages of SIGN PT is that you do not need to obtain your own Autoridade Tributária e Aduaneira (AT) certification. The AT certification process typically takes 6 to 12 months and requires significant technical and legal effort. By integrating SIGN PT, you operate under an already-certified environment — which means your software can be compliant in Portugal from the moment your integration is complete, not a year later.

Most ISVs and POS providers can complete a basic SIGN PT integration within days using our developer documentation and sandbox environment. fiskaly provides comprehensive API documentation, quickstart guides, and direct technical support to reduce friction at every step. The sandbox environment allows you to test the full invoice flow — including ATCUD generation and SAF-T — before going live in production.

Portuguese law (Decree-Law 28/2019) requires a specific offline fallback: if the certified invoicing path is unavailable for any reason, businesses must issue pre-printed documents from an AT-authorized printer and later recover them into the certified software. SIGN PT is designed to make this recovery process straightforward and fully auditable, in compliance with both Decree-Law 28/2019 and Order 8632/2014.

Yes — and this is one of SIGN PT's core use cases. International POS and ERP providers often face significant friction when entering Portugal: AT certification requirements, ATCUD mechanics, SAF-T format specifics, and the upcoming QES mandate. SIGN PT removes all of these barriers with a single, expert-maintained API. You focus on your product expansion; we handle the regulatory complexity.

Yes. You have full access to our test environment to generate fatura, fatura-recibo, or fatura simplicada, among others, without affecting the production AT credentials or fiscal records. Contact our team and try it today for free, no commitments.