Understanding Portugal’s Latest E-Invoicing Regulatory Updates

Portugal mandates e-invoicing for B2G transactions. Learn about new regulations, eSPap’s platform, and CIUS-PT standards for VAT compliance.

Ajith Kumar M
November 30, 2023
6 min

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Portugal has joined other European nations in mandating e-invoicing for business-to-government transactions. This article sheds light on the new e-invoicing regulations in Portugal, including the use of eSPap’s platform and CIUS-PT standards, aimed at enhancing VAT compliance and reducing tax fraud in public procurement.

Key Regulatory Updates

Portugal's recent e-invoicing regulations mark a significant shift, particularly for Public Administration suppliers. Key deadlines to note:

  • Large Companies: Compliance since January 1, 2021.
  • Micro, Small, and Medium-sized Enterprises: Deadline extended to January 1, 2024.

These changes, steered by Decree-Law no. 54/2023, align with the evolving digital landscape in public procurement.

Compliance Essentials

Complying with these new regulations involves understanding various components:

  • Infrastructure: FEAP for B2G transactions.
  • Formats: CIUS PT standard for B2G.
  • eSignature Requirements: Essential for non-EDI invoices, effective from January 1, 2024.
  • Archiving Period: Mandatory 10-year period.

The FE-AP Solution

eSPap's FE-AP solution is instrumental for public entities and suppliers, facilitating a smoother transition to the new e-invoicing standards. With a substantial number already onboard, it's a pivotal tool for compliance.

Invoice QR Code and ATCUD in Portugal:

  • The Portuguese tax authority requires billing documents to feature an Invoice QR Code and ATCUD.(Understanding Unique Document Code (ATCUD)
  • The QR Code and ATCUD include details like Tax Registration Numbers, Document Type, Status, Date, Tax Amounts, and more.
  • ATCUD is a unique document code, comprising the validation code of the document series and a sequential number, as mandated by the Portuguese tax authority.

Supplier Onboarding

Suppliers yet to transition can refer to the CIUS-PT implementation guide for a structured onboarding process. This ensures a seamless integration into the e-invoicing ecosystem.

Legislative Landscape

Understanding the legislative backdrop is crucial. Key documents include Decree-Law 123/2018 and Order No. 289/2019, alongside the European standard on eInvoicing (UBL 2.1 or/and XML-GS1).

Platforms for Implementation

Portal BASE and Plataforma Eletrónica de Compras are among the platforms supporting these changes, offering comprehensive solutions for e-invoicing processes.

Compliance.io: Your Global E-Invoicing Partner

In this evolving landscape, choosing the right compliance partner is vital. Compliance.io stands out as a robust platform, offering global e-invoicing solutions tailored to diverse business needs. Its comprehensive features ensure that your business not only meets Portugal's regulatory requirements but also aligns with global e-invoicing standards.


Staying updated and compliant with Portugal's e-invoicing regulations is crucial for businesses engaged in public contracts. Utilizing platforms like Compliance.io can significantly ease this transition, ensuring efficient and compliant business operations.

For more detailed information, always refer to the official legislative documents and consider consulting experts for personalized guidance.

This version provides a succinct yet informative overview of the regulatory changes, compliance requirements, and the benefits of using Compliance.io for global e-invoicing needs.