Portugal Authenticity and Integrity E-invoicing Requirements

Kelly Muniz
May 31, 2022

Update 19 December 2022 by Carolina Silva

New grace period for invoice reporting and postponement of stricter integrity and authenticity requirements

The Portuguese State Secretary of Fiscal Affairs (SEAF) recently issued issued Order 8/2022 XXIII, which introduces a grace period for reporting obligations, as well as yet another of the stricter integrity and authenticity (I&A) requirements for electronic invoices.

The Order aims to highlight and promote Portugal’s plans to reduce the invoice data reporting obligations time window, as established by article 3 of Decree-law 198/2012. The Order also aims to establish the constant move towards real-time transmission of invoice data, as observed in other countries throughout the world.

Additionally, the Order affects the requirements of Decree-law 28/2019, by which the Portuguese government enacted a series of measures concerning invoice issuance, processing, and archiving, with the aim of simplifying and digitizing invoicing compliance in the country.

Changes in invoice reporting obligations

Since 2019, the Portuguese government has continuously reduced the time window for the invoice data reporting obligation. Starting 1 January 2023, the deadline for the monthly communication of invoice data will be until the 5th day of the month following the issuance of the invoice.

The new Order introduces a grace period concerning this obligation, with no penalties applied if reporting is carried out until the 8th day of the month following the invoice issuance. This is also applicable for cases where there is non-issuance of invoices during the relevant time period, where a nil monthly submission should also be made until the 8th day of each month.

The Portuguese government has also decided to implement a system of informative alerts by the tax authority in 2023. The aim is to promote voluntary compliance within the 5-day deadline by notifying taxpayers who don’t communicate invoice data until the 5th of the month following the issuance of the invoice.

Postponement of the stricter e-invoice integrity and authenticity requirements

Decree-law no. 28/2019 established several measures regarding invoicing, including a stricter integrity and authenticity requirement for invoices and fiscally relevant documents issued electronically. One of these requirements is the obligation to apply a qualified electronic signature (QES) or seal or use electronic data exchange system (EDI) for e-invoices, as per the European model.

This requirement has been postponed multiple times since enacted and was due to become mandatory on 1 January 2023. The newly published Order, however, explicitly states that until the 31 December 2023 all PDF invoices are considered electronic invoices for all fiscal effects.

Therefore, from the 1 January 2024, taxpayers must comply with the requirement of applying a QES or use EDI per the European Model to ensure integrity and authenticity of e-invoices.

Additional upcoming Portuguese requirements

Besides the stricter integrity and authenticity requirement and the grace period for communication of invoice data, taxpayers are expected to comply with new e-invoicing mandates underway in Portugal.

Namely, the mandatory B2G invoicing in the CIUS-PT format starting on 1 January 2023 for medium, small and micro enterprises. No further guidance has been issued at this time regarding a postponement of the adoption of the CIUS-PT format for these last taxpayer groups, meaning that public entities may reject invoices issued in other formats after the go-live date.

Still have questions about Portugal’s e-invoicing requirements? Speak to our tax experts.


Update 31 May 2022 by Kelly Muniz

Portugal: Postponement of the Stricter Authenticity and Integrity Requirements

In 2019, the Portuguese government enacted Law Decree n. 28/2019, introducing a full reform of the rules concerning the issuance, processing and archiving of invoices, with the main goals of implementing electronic invoicing, simplifying compliance for taxpayers and reducing the VAT gap.

The expanded scope of those obliged to use a billing software certified by the Portuguese Tax Authority, the inclusion of a QR code and a sequential unique number code (ATCUD – código único de documento) and the stricter integrity and authenticity requirements when issuing invoices and other relevant fiscal documents were some of the most impactful mandates introduced by this law.

However, many taxpayers struggled to comply with the new requirements. As such, the tax authority has delayed the launch of different components of the Decree, and some of them remain to be implemented.

In a recent Ministerial Decision from 26 May 2022, the goal line for implementing the stricter integrity and authenticity requirement, this article’s focal point, has been moved yet again, now to 1 January 2023.

The stricter integrity and authenticity requirement

The Decree from 2019 established that in order to guarantee the requirements of authenticity and integrity of electronic invoices and other relevant fiscal documents have been met (per article 233 of the EU VAT Directive 2006/112/EC), taxpayers must use a qualified electronic signature, a qualified electronic seal (QES) or an electronic data exchange system (EDI) with security measures per the European Model EDI Agreement. This change is important as it limits the choice of compliance methods generally recognised within the EU to one between only QES and EDI.

To achieve this goal, the Decree determined that taxpayers would only be able to use previously accepted advanced electronic signatures or seals (the lower level of signature security) until 31 December 2020. After that, all invoices would be required to incorporate a qualified signature or seal or be issued through EDI.

When is the new deadline?

The original deadline for implementing the stricter integrity and authenticity requirements has been postponed many times. The first delay was ordained through Despacho n. 437/2020-XXII of 9 November 2020 of the State Secretary for Fiscal Matters (SEAF – Secretário de Estado dos Assuntos Fiscais). According to this, PDF invoices without a QES would be accepted until 31 March 2021 and considered electronic invoices for all fiscal purposes.

Since then, the mandate has been postponed four additional times, with the last one taking place on 26 May 2022, by Despacho n. 49/2022-XXIII of the SEAF. According to this act, PDF invoices with no specific security measures must be recognised as electronic invoices for fiscal effects until 31 December 2022, instead of the previously established date, 30 June 2022.

Therefore, from 1 January 2023, taxpayers covered by Law Decree n. 28/2019 must comply with the requirement to ensure authenticity and integrity either by applying a Qualified Electronic Signature/Seal or by using “EDI by-the-book” (EDI under the European Model EDI Agreement).

Additional upcoming requirements

Besides the stricter authenticity and integrity requirement, taxpayers must be ready to comply with additional new invoicing mandates underway in Portugal. On 1 July 2022, it will be required to only use structured electronic invoices in CIUS-PT format for B2G transactions. The B2G mandatory e-invoicing is already under implementation through a phased roll-out. It is set to be finalised and become compulsory for small and medium companies and microenterprises on 1 July 2022. Furthermore, the inclusion of the ATCUD code on invoices and other fiscal relevant documents, which has also been previously postponed, is set to become mandatory on 1 January 2023.

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Kelly Muniz

Kelly Muniz is a Junior Regulatory Counsel at Sovos. Based in Stockholm and originally from Brazil, Kelly earned a Bachelor’s degree in Law in her home country, where she worked as a licensed lawyer. She also holds a Master’s degree in EU Business Law from Lund University in Sweden.
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