Portugal e-Invoicing Guide

Portugal mandates e-invoicing only for public procurement. Large suppliers to the public sector have had to issue structured CIUS-PT e-invoices since 1 January 2021, and micro, small and medium enterprises join on 1 January 2027. There is no B2B or B2C mandate: under article 12(1) of Decreto-Lei n.º 28/2019, invoices may be issued electronically only where the recipient accepts them.

Outside public procurement, the tax authority sees invoices through reporting rather than exchange. Invoices issued by software certified by the Autoridade Tributária e Aduaneira (AT) carry a QR code and the ATCUD unique document code, and their data must reach the Portal das Finanças by the 5th day of the month following issuance. PDF invoices count as electronic invoices until 31 December 2026.

The State and public institutes have had to receive and process e-invoices since 18 April 2019, and the remaining public buyers followed on 18 April 2020. The issuing obligation reached large suppliers on 1 January 2021. On the domestic side, the QR code became a required invoice element on 1 January 2021 and the ATCUD on 1 January 2023. Since 5 January 2026 suppliers can also issue B2G e-invoices from the AT invoicing application in the Portal das Finanças.

Under Lei n.º 73-A/2025, the law in force, the PDF derogation and the SME dispensation in public procurement both end on 31 December 2026, and the accounting SAF-T (PT) applies to periods from 2027, delivered in 2028 or later. The Government's 2027 State Budget proposal, Proposta de Lei n.º 110/XVII/2.ª, admitted by Parliament on 8 October 2026, would move each of these by a year. It is not law: until it is enacted, the dates in Lei n.º 73-A/2025 apply. At EU level, the main e-invoicing and digital reporting rules of Council Directive (EU) 2025/516 apply from 1 July 2030.

The B2G obligation comes from article 299.º-B of the Código dos Contratos Públicos and applies to large suppliers today. Micro, small and medium enterprises as defined by Commission Recommendation 2003/361/EC, and public bodies acting as co-contractors, may keep using other invoicing mechanisms until 31 December 2026 under article 9(4) of Decreto-Lei n.º 111-B/2017, as amended by Decreto-Lei n.º 13-A/2025 and extended by article 260(2) of Lei n.º 73-A/2025, so their obligation starts on 1 January 2027. No e-invoice is needed where the purchase results from a simplified direct award under article 128(3) of the Código dos Contratos Públicos, or where the contract is declared secret or carries special security measures.

For any electronic invoice, authenticity of origin and integrity of content are deemed guaranteed where, in particular, a qualified electronic signature, a qualified electronic seal under Regulation (EU) No 910/2014, or an EDI system following the European Model EDI Agreement is used, per article 12(2) of Decreto-Lei n.º 28/2019. PDF invoices with none of these stay valid electronic invoices for tax purposes until 31 December 2026 under article 95(3) of Lei n.º 73-A/2025. Books, records and supporting documents are kept for 10 years; electronic archives may be held in any EU Member State, while archiving outside the European Union needs prior authorisation from the AT.

Portugal follows a post-audit model with neither clearance nor a real-time reporting obligation. Invoices are issued through certified or AT-provided invoicing software, other electronic means or authorised pre-printed forms and are exchanged directly between the parties. B2G e-invoices reach public buyers through FE-AP, the platform eSPap runs for public bodies to receive and process them, or through a buyer's own platform. The CIUS-PT semantic model builds on EN 16931, and its UBL 2.1 syntax representation is published at version 2.1.1; the CEFACT CII representation is still under construction. Suppliers can also issue B2G invoices and rectifying documents free of charge from the AT invoicing application, which forwards them to FE-AP.

Invoice data goes to the tax authority after issuance, by webservice, by SAF-T (PT) file upload or by direct entry on the Portal das Finanças, no later than the 5th day of the following month. A separate accounting SAF-T (PT) file under Portaria n.º 31/2019 applies to periods from 2027 and is to be delivered in 2028 or later under the law in force.

Invoicing fines sit in the RGIT. They cover not issuing invoices or receipts or issuing them late, not demanding or keeping them, and failing or delaying the declarations, communications and other records that tax law requires. Under article 26(4) of the RGIT, the minimum and maximum of each fine are doubled for companies and other legal persons.