Invoicing in Portugal: New Rules, Mandatory Requirements, and Tax Regulation Updates

Find out everything about the new invoice issuing obligations: use of certified programs, QR Code, ATCUD, and communication with AT.

Portugal has taken significant strides toward the digitalization of its tax system. With the implementation of Decree-Law No. 28/2019, businesses and self-employed professionals face new invoicing obligations and regulatory changes that are shaping how financial operations are managed—now and into 2025.

This article summarizes the key updates introduced by this law, including mandatory invoicing features like the QR Code, ATCUD (Unique Document Code), electronic archiving, and compliance requirements surrounding fixed-term employment contracts. Whether you're a tax professional or business owner, understanding these changes is essential for staying compliant and avoiding costly penalties.

Key Changes Under Decree-Law No. 28/2019

Certified Billing Software Is Now Mandatory

Since 2019, businesses with a turnover of €75,000 or more have been required to use invoicing software certified by the Portuguese Tax and Customs Authority (AT). This threshold dropped to €50,000 in 2020, and now the rule applies to all VAT taxpayers with organized accounting, regardless of revenue.

Limited Exemptions from Invoicing

The ability to forego issuing an invoice is now extremely limited. It’s only allowed in very specific circumstances, such as museum admissions or cultural events, provided a valid payment document is issued. For nearly all commercial transactions, invoicing is mandatory.

Paperless Invoicing and Real-Time Reporting

Paper invoices are no longer required if:

• The invoice includes the buyer’s NIF (Tax ID)

• It’s issued through AT-certified software

• It’s reported to the AT in real time

• The customer agrees to forgo a printed copy

  
  

To use this paperless option, businesses must notify the Tax Authority via the Tax Portal.

Mandatory QR Code on Invoices

As of January 1, 2021, all invoices must include a QR code. This code aggregates key information—buyer/seller details, VAT, totals—and allows customers to scan and upload invoices directly to the eFatura Portal, eliminating manual data entry.

Introduction of ATCUD (Unique Document Code)

Effective January 1, 2022, ATCUD must appear on all tax-relevant documents. This code ensures traceability and transparency and is generated after pre-registering your invoice series with the Tax Authority.

Communication of Invoice Series

Since July 1, 2021, companies must pre-communicate the document series they plan to use. This is essential for generating a valid ATCUD. Failure to do so invalidates invoices and can result in fines.

Mandatory Reporting of Establishments and Billing Equipment

All businesses must inform the AT of:

• The physical locations where invoices are issued

• The software and equipment used for billing

This notification must be submitted within 30 days of starting business or making relevant changes.

Invoice Communication Deadlines

As of now, invoices must be reported to the AT by the 12th of the following month. Submission can be done via web service, SAF-T file upload, or manually through the eFatura portal.

Electronic Archiving

Decree-Law No. 28/2019 also allows for the electronic storage of documents. Paper invoices can be digitized if they meet AT’s standards for readability and integrity, making compliance easier and archiving more efficient.

Termination of Fixed-Term Contracts: A Tax Perspective

The legislation also touches on labor-related matters. Specifically, the termination of fixed-term employment contracts now carries tax implications. These terminations must be carefully documented and reported to ensure compliance with Portugal’s tax and labor laws.

Looking Ahead: Digital Signatures Required by 2026

From 2026, all PDF invoices must include a qualified digital signature to be valid. This change further strengthens document authenticity and aligns with EU-wide digital security standards.

Frequently Asked Questions

Who must use certified invoicing software? All VAT-registered taxpayers with organized accounting.

Can I issue an invoice without printing it ? Yes—if the customer agrees and the invoice is reported to AT in real time via certified software.

What is ATCUD, and is it mandatory? It’s a unique document code required since January 1, 2022, ensuring traceability and control.

Is a QR code required? Yes, since January 1, 2021.

Do I need to report my invoice series to AT? Yes, this is mandatory prior to issuing invoices in that series.

Final Thoughts

The evolution of invoicing in Portugal is a clear move toward greater transparency, traceability, and digital efficiency. With the implementation of QR codes, ATCUD, and upcoming digital signatures, businesses are expected to modernize quickly or risk falling behind.

Moreover, these updates extend beyond billing. As labor and tax regulations tighten around contracts and reporting, compliance is no longer optional—it’s a strategic necessity.

Need help staying compliant in Portugal?

INLIS Consulting specializes in helping businesses and freelancers navigate the new tax and invoicing landscape. From certified billing systems to employment contract advisory, we ensure your company is ready for 2025 and beyond.

Contact us today for a consultation.