Portugal: E-Invoicing and E-Reporting Guide

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Slide deck

Executive orientation. Portugal has no general B2B e-invoicing clearance mandate (no SDI-style platform, no mandatory Peppol B2B, no real-time approval). It instead operates one of Europe’s strictest post-issuance digital tax regimes built on AT-certified software, mandatory ATCUD + QR codes, a hash chain, and monthly SAF-T (PT) Billing reporting. Structured e-invoicing is mandatory only for B2G (CIUS-PT). A Qualified Electronic Signature (QES) becomes mandatory for PDF invoices from 1 January 2027, and annual SAF-T Accounting from FY 2027 (first file due 2028). 

1. Introduction & Country Context

1.1. Tax digitalisation journey 

• Portugal was the first country in the world to adopt the OECD Standard Audit File for Tax, introducing SAF-T (PT) via Portaria n.º 321-A/2007 with effect for billing systems from 1 January 2008 and accounting from FY 2008. 

• Certified invoicing software became mandatory from 2010–2011 (Portaria n.º 363/2010), the true start of the modern fiscal-control system; monthly reporting of invoice data to the tax authority (e-Fatura) followed in 2013. 

• Decreto-Lei n.º 28/2019 consolidated invoicing, dematerialisation and archiving rules. QR codes became mandatory from 1 January 2022 and the ATCUD unique document code from 1 January 2023. 

• B2G structured e-invoicing (CIUS-PT) has phased in since 2021 and extended to SME/micro suppliers from 1 January 2026. The next domestic milestone is the QES requirement on PDF invoices from 1 January 2027. 

Sources: RTC – E-Invoicing in Portugal (2026)  |  Fiskaly – Fiscalization ATCUD/SAF-T/QES  |  Portal das Finanças – SAF-T (PT) 

1.2. Rationale for the mandate 

• Reduction of the VAT gap and fraud prevention through full transaction transparency – the Ministry of Finance credits e-Fatura with a significant drop in VAT fraud since 2013. 

• Administrative modernisation and simplification – the data feed now powers pre-filled (“automatic”) VAT returns and consumer tax-deduction claims. 

• Alignment with EU and international trends (Directive 2014/55/EU for B2G; OECD SAF-T; and the direction of travel toward ViDA digital reporting). 

Sources: ERP Implementation – e-fatura & SAF-T 2026-2027  |  EC – eInvoicing in Portugal 

1.3. Regional / international positioning 

• Early mover on reporting (SAF-T since 2008/2013), but a follower on structured B2B e-invoicing – there is still no B2B clearance obligation, unlike Italy (SdI) or Spain (SII). 

• The model is a decentralised / post-audit reporting model rather than a Continuous Transaction Control (CTC) clearance model. 

• Relative to the EU ViDA timeline (package published 25 March 2025), Portugal is aligned on B2G/EN 16931 but has not yet legislated a domestic B2B DRR; it will need to align with the intra-EU cross-border DRR from 1 July 2030 and domestic alignment by 2035. 

Sources: ValidateFin – Portugal mandate overview  |  e-invoice.app – Portugal timeline 

1.4. Supranational authorisation / derogation 

• Not applicable for a B2B mandate. Because Portugal has not imposed mandatory B2B structured e-invoicing, it has not sought (and does not currently need) a Council Implementing Decision derogating from Articles 218/232 of the VAT Directive. 

• Under ViDA (in force from 14 April 2025), Member States may in any case now mandate domestic e-invoicing without prior Commission authorisation – so any future Portuguese B2B mandate would not require a derogation. 

• B2G rests on the transposition of Directive 2014/55/EU (Decreto-Lei n.º 111-B/2017), not on a derogation. 

Sources: VATcalc – ViDA removes e-invoicing legal barriers  |  Fiscal Solutions – no B2B clearance mandate 

2. Regulatory Framework (Laws, Decrees, Regulations, Circulars, FAQs)

2.1. Primary legislation 

• Código do IVA (CIVA). Core VAT rules – Article 36 (invoice content and 5-business-day issuance deadline), Article 40 (simplified invoices), Article 41 (electronic invoices have equal legal status where authenticity and integrity are ensured), Article 52 (10-year retention). 

• Decreto-Lei n.º 28/2019 (de 15 de fevereiro). The central invoicing / dematerialisation / archiving decree – certified software, QR code and ATCUD basis, dematerialised archiving, and the QES/qualified-seal/EDI authenticity options (Article 12). 

• Decreto-Lei n.º 111-B/2017. Transposes Directive 2014/55/EU and establishes mandatory B2G e-invoicing (as amended by Decreto-Lei n.º 123/2018 and successive budget/decree measures). 

• Portaria n.º 321-A/2007. Establishes the SAF-T (PT) standardised XML file (amended by Portaria 1192/2009, Portaria 160/2013, Portaria 302/2016, etc.). 

• Lei n.º 73-A/2025 (OE2026, 30 December 2025). The 2026 State Budget – postpones the mandatory QES on PDF invoices to 1 January 2027 and the annual SAF-T Accounting file to FY 2027 (first submission 2028). 

Official publication: all texts are published in the Diário da República (diariodarepublica.pt) and consolidated on the Portal das Finanças). 

Sources: Invoice-Portal – legal foundations (CIVA, DL 28/2019)  |  EDICOM – B2G legal framework  |  KPMG – 2026 Budget postponements 

2.2. Implementing regulations, decrees & orders 

• System usage & technical standards: Portaria n.º 363/2010 (software certification / Modelo 24); Portaria n.º 195/2020 (ATCUD structure, communication of series, and QR code technical specification); AT technical specifications for the QR code and ATCUD. 

• SAF-T structure amendments: Portaria n.º 302/2016 (updated data structure and taxonomies for IES Annexes A/I), building on Portarias 1192/2009 and 160/2013. 

• VAT-return / reporting adaptations: Portaria n.º 221/2017 (periodic VAT return models), substantially amended by Portaria n.º 298/2026/1 (16 July 2026) to restructure boxes and enable pre-filling (most changes from 1 July 2027; VAT-group and Housing-Package blocks from 1 July 2026). 

• B2G platform governance: Decreto-Lei n.º 123/2018 and eSPap rules governing the FE-AP platform and phased entry dates. 

Sources: ValidateFin – legal basis list  |  VATupdate – Portaria 298/2026/1 VAT-return overhaul 

2.3. Circulars, official guidance & FAQs 

• The AT maintains guidance, FAQs, information leaflets (folhetos) and manuals on the e-Fatura) and SAF-T (PT)) sections of the Portal das Finanças, including the certified-software (“Produtores de Software”) area and the SVAT validation seal. 

• Transitional guidance confirms PDF invoices remain valid electronic invoices until 31 December 2026 and QES applies from 1 January 2027 (KPMG, Meridian, Dynatos, Fonoa briefings, Dec 2025). 

• No formal “soft-landing” circular has been published for a B2B mandate (there is none); enforcement of existing certified-software / ATCUD / QR / SAF-T obligations is already live. 

Sources: KPMG TaxNewsFlash  |  Meridian Global Services  |  Descodify – PDF invoices 2026/2027 

2.4. Supranational / international legal basis 

• EU B2G: Directive 2014/55/EU (EN 16931) transposed by Decreto-Lei n.º 111-B/2017; contracting authorities must accept EN-compliant e-invoices above EU procurement thresholds. 

• No Article 218/232 derogation is in force for a B2B mandate (none exists). Under ViDA, prior EU authorisation is no longer required to introduce domestic e-invoicing. 

Sources: EC – eInvoicing in Portugal  |  VATcalc – ViDA legal barriers removed 

3. Scope of the Mandate

3.1. Transactions in scope 

• Domestic B2B: No structured e-invoicing mandate. Paper, PDF and structured formats are all permitted by mutual agreement, but every invoice must be issued by AT-certified software and carry ATCUD + QR code and be reported via SAF-T Billing. From 1 January 2027 a PDF invoice must carry a QES to count as an electronic invoice. 

• Domestic B2G: Mandatory structured e-invoicing (CIUS-PT) for suppliers; contracting authorities must be able to receive it via FE-AP/eSPap. Large suppliers since 2021; SME/micro from 1 January 2026 (PDF tolerated through 31 December 2026). 

• Domestic B2C: No structured e-invoicing mandate. Invoices/simplified invoices still require certified software, ATCUD and a QR code; consumers can register invoices under their NIF via e-Fatura for tax deductions and the “Fatura da Sorte” lottery. 

• Cross-border B2B – intra-EU supplies (outbound): Must be issued by certified software with ATCUD/QR and reported in SAF-T Billing. No separate clearance. 

• Cross-border B2B – exports (outbound): Same certified-software / SAF-T Billing obligations; the export is zero-rated and flagged accordingly in the file. 

• Inbound / intra-EU acquisitions & imports: Invoices received from foreign suppliers are not subject to the Portuguese issuance rules; they are captured on the buyer side through e-Fatura classification and the (pre-filled) VAT return, and via reverse-charge/acquisition reporting. 

Sources: Fiscal Solutions – scope summary  |  The Invoicing Hub – Portugal 

3.2. Special transactions in scope 

• Self-billing (autofaturação): In scope. Permitted under Article 36 CIVA + DL 28/2019; must use certified software, carry the mention “autofaturação”, and be reported through a dedicated SAF-T Self-Billing (S) file / e-Fatura. 

• Triangulation & chain transactions: Invoices issued by a Portuguese-registered party are in scope for certified software, ATCUD/QR and SAF-T Billing; simplified triangulation carries the standard reverse-charge annotations. 

• Special VAT regimes: Margin schemes (used goods, works of art, travel agents), flat-rate farmers and investment gold remain within the certified-software/SAF-T framework; the revised VAT return (Portaria 298/2026/1) adds dedicated margin-scheme fields. 

Sources: EasyFin – self-billing rules  |  SAP – SAF-T Self-Billing (Autofaturação) 

3.3. Excluded or exempt transactions 

• There is no B2B/B2C structured e-invoicing obligation to be excluded from; the relevant exclusions relate to the QES requirement, the B2G mandate and the pre-filled VAT return rather than to a clearance system. 

• B2G exclusions: certain low-value or specific contracts and public recipients not reachable via FE-AP (alternative channels agreed bilaterally). 

• Pre-filled VAT return (IVA Automático+) excludes taxpayers doing imports/exports, self-supplies where the taxpayer is the acquirer, and any special/particular VAT regime, and excludes cash-VAT registrants. 

• General VAT documentation exemptions (e.g. certain exempt financial/insurance services, OSS/IOSS reporting) follow ordinary CIVA rules, not a separate e-invoicing exclusion list. 

Sources: AT – IVA Automático (leaflet)  |  EDICOM – B2G channels 

4. Taxable Persons in Scope

4.1. Established domestic entities 

• All VAT-registered businesses established in Portugal (companies, partnerships, sole traders) issuing invoices must use certified software with ATCUD/QR and report SAF-T Billing monthly. 

• Small taxpayers below defined thresholds may be exempt from certified software in narrow cases, but in practice the vast majority use certified solutions; the AT publishes the certified-software list. 

4.2. Non-established entities 

• Foreign entities with a fixed establishment: Treated like residents – certified software, ATCUD/QR and monthly SAF-T Billing are mandatory. 

• Foreign entities VAT-registered without a fixed establishment: In scope since 1 January 2023 – must issue via certified software with ATCUD/QR and file monthly SAF-T Billing (or report directly to AT). 

• Foreign entities without Portuguese VAT registration: Outside the Portuguese issuance obligations (no domestic invoices to issue). 

4.3. Voluntary participation 

• There is no voluntary B2B clearance to join. ATCUD may be applied voluntarily where not otherwise required, and businesses may voluntarily adopt structured formats/Peppol ahead of any future obligation. 

4.4. Sector-specific rules & exemptions 

• No blanket sector carve-outs from certified software/SAF-T. Sector nuances arise mainly in special VAT regimes (travel, margin schemes, agriculture, financial/insurance exemptions) handled within CIVA and the SAF-T structure. 

Sources: ERP Implementation – who is in scope (incl. non-residents)  |  VATcalc – non-resident 3 obligations since 2023  |  VATupdate – SAF-T non-residents 

5. Implementation Timeline

5.1. Legislative history 

• 2007/2008: SAF-T (PT) introduced (Portaria 321-A/2007). 2010–2011: certified software (Portaria 363/2010). 2013: monthly e-Fatura reporting. 2019: DL 28/2019 consolidation. 

• 2021–2023: B2G for large companies (2021); QR code (2022); ATCUD (2023); non-resident obligations (2023). 

• 2025–2026: Lei n.º 73-A/2025 (OE2026) confirms QES from 2027 and SAF-T Accounting FY2027/2028; B2G extended to SME/micro from 1 January 2026. 

• No EU derogation period applies (no B2B mandate). 

5.2. Voluntary or pilot phases 

• No formal B2B pilot. IVA Automático+ pre-filled VAT return went live for eligible resident taxpayers for operations from 1 July 2025 (built on earlier IVA Automático from 2020). 

5.3. Mandatory go-live dates 

• B2G large enterprises: 1 January 2021. 

• QR code (all invoices): 1 January 2022. ATCUD (all invoices): 1 January 2023. 

• Non-resident VAT-registered obligations: 1 January 2023. 

• B2G SME/micro suppliers: 1 January 2026 (PDF tolerated as e-invoice through 31 December 2026). 

• QES on PDF e-invoices: 1 January 2027. 

• Annual SAF-T Accounting: FY 2027 data, first file due in 2028. 

• Obligation to receive: for B2G, contracting authorities have been required to receive EN-compliant e-invoices since 2019/2020. There is no separate B2B “obligation to receive”. 

5.4. Grace periods & transitional provisions 

• PDF invoices remain valid as electronic invoices without QES until 31 December 2026. Paper printing remains permitted; inventory-valuation temporary exemptions applied for 2025–2026. 

5.5. Pre-mandate milestones 

• Series must be communicated to AT (via Portal das Finanças / API) to obtain the ATCUD validation code before issuing documents in a series; certified-software producers register with AT. 

5.6. Known or anticipated postponements 

• QES has been postponed three times: originally 2021/2025 → 2026 → 2027. SAF-T Accounting has been repeatedly deferred (→ FY2027/2028). Further slippage cannot be excluded but is not currently announced. 

Sources: e-invoice.app – full timeline  |  VATcalc – SAF-T Accounting 2027 delay  |  Dynatos – delays to 2027  |  AT – IVA Automático+ live 

6. How E-Invoicing & E-Reporting Really Work — The Operating Model

6.1. Overview of the operating model 

• Model type: Post-audit / decentralised reporting model – not centralised clearance. Invoices are issued and exchanged directly between parties; data is reported to AT after issuance (monthly SAF-T Billing) and near-real-time to e-Fatura. 

• B2G uses a decentralised exchange (FE-AP/eSPap, Peppol-capable) for structured CIUS-PT invoices. 

• The tax authority does not validate/clear individual invoices before issuance; it controls integrity through certified software + hash chain + ATCUD/QR and post-issuance SAF-T reconciliation. 

6.2. Step-by-step invoice lifecycle (domestic B2B/B2C) 

• Step 1 – Creation: AT-certified software generates the invoice, assigns the sequential number, computes the ATCUD and the hash-chain digital signature (RSA), and prints the QR code. 

• Step 2 – Issuance/exchange: The invoice (paper, PDF or structured) is delivered directly to the customer within 5 business days of supply. 

• Step 3 – Reporting: Invoice data is communicated to e-Fatura and consolidated in the monthly SAF-T Billing file, due by the 5th of the following month. 

• Step 4 – (No clearance): There is no fiscal validation code issued per invoice; the ATCUD (allocated from a pre-communicated series) plays the traceability role. 

• Step 5 – Delivery to buyer: Directly by the supplier; for B2G, via FE-AP/eSPap. 

• Step 6 – Retrieval by buyer: Buyers view/classify received invoices in e-Fatura (portal/API) for VAT deduction and pre-fill. 

• Step 7 – Archiving: By the taxpayer for 10 years (see chapter 13); e-Fatura also holds the reported data. 

6.3. Authentication & access methods 

• Access to the Portal das Finanças / e-Fatura via NIF + password, or Chave Móvel Digital / Cartão de Cidadão (national eID); machine access via web-service credentials/API and digital certificates. 

• Third parties (accountants – contabilistas certificados, fiscal representatives) are authorised through the Portal das Finanças delegation of powers; self-billing requires a prior written agreement. 

6.4. Offline / contingency mode 

• Certified software can operate offline and still generate compliant documents (ATCUD/QR and hash chain); the data is transmitted to e-Fatura and included in the monthly SAF-T Billing when connectivity returns – there is no per-invoice clearance to wait for. 

6.5. Buyer-side workflow 

• Buyers retrieve and classify invoices in e-Fatura; classification (business vs. non-business, goods vs. services) drives input-VAT deduction and pre-filling. Buyer acceptance is not required for validity in B2B (except self-billing acceptance). 

6.6. QR code / verification code 

• A QR code is mandatory on every paper/PDF invoice (and may be bypassed only in structured EDI flows). It encodes ~18 fields including issuer/acquirer NIF, document type/number, date, ATCUD, taxable amounts, VAT by rate and the certified-software number, enabling AT and consumers to verify the document. 

Sources: RTC – operating layers & lifecycle  |  VATcalc – QR code / ATCUD data fields  |  Zunapro – 18-field QR, hash signature 

7. Acceptable E-Invoice Formats — Mandatory & Voluntary

7.1. Mandatory format(s) 

• B2G (mandatory structured): CIUS-PT – the Portuguese national adaptation of EN 16931, implemented as UBL 2.1 (CIUS-PT) or UN/CEFACT CII (CIUS-PT), both XML. 

• B2B/B2C: No mandatory structured format – paper, PDF or structured formats are all valid, but must be produced by certified software with ATCUD/QR (and, from 2027, a QES on PDFs). 

• Structure of CIUS-PT: header/process identifiers, seller/buyer sections, contract reference, delivery/payment terms, line items, allowances/charges, tax breakdown and totals per EN 16931. 

7.2. Relationship to international / regional standards 

• CIUS-PT is a Core Invoice Usage Specification of EN 16931; it is Peppol BIS 3.0-compatible and exchangeable over Peppol via FE-AP/eSPap. 

• National extensions/deviations: mandatory Portuguese NIF as routing identifier and AT-specific document codes/business rules (e.g. PT-R-001 NIF, PT-R-004 ATCUD). 

7.3. Voluntary / legacy / transitional formats 

• PDF (with QR, and QES from 2027) and paper remain valid for B2B/B2C. EDI is permitted where an audit trail is guaranteed (Article 12 DL 28/2019). No Factur-X/ZUGFeRD hybrid mandate exists. 

• Transitional: PDF accepted as an e-invoice through 31 December 2026 without QES. 

7.4. Attachments 

• In structured CIUS-PT, EN 16931 attachment mechanisms (embedded binary or external reference) are technically available; the structured data remains the formal invoice, with attachments as supplementary documentation. For paper/PDF, the invoice document itself is the formal record. 

Sources: Fiskaly – CIUS-PT / UBL 2.1  |  Invoice Navigator – formats & rejection codes  |  EDICOM – UBL/CEFACT CIUS-PT 

8. Technical & Functional Requirements

8.1. E-invoice specifications 

• Mandatory data fields (Article 36 CIVA): issue date and supply date; sequential number; supplier name/address/NIF; customer name/address/NIF (for B2B); description, quantity and unit price of goods/services; taxable amount per rate; applicable VAT rate(s) and VAT amount; exemption/legal basis where applicable; ATCUD; certified-software number; and the QR code. 

• Conditional/optional fields: delivery address, order/contract references, allowances/discounts, self-billing and reverse-charge mentions, fiscal-representative details, cash-VAT mention where relevant. 

• Validation rules: gap-free sequential numbering per series, hash-chain continuity, correct NIF format, date formats and calculation alignment (line/tax/total consistency); for CIUS-PT, EN 16931 business rules plus PT rules. 

8.2. E-reporting specifications 

• Format: SAF-T (PT) XML (current billing schema, e.g. v1.04_01). Four file types – Integrated (I), Accounting/Contabilidade (C), Billing/Faturação (F) and Self-Billing (S). 

• SAF-T Billing content: header, master files (customers, suppliers, products, tax table) and source documents (invoices, credit/debit notes, receipts, movement of goods). 

• New/related fields: ATCUD, QR data and certified-software identifiers feed the file; the revised VAT return (Portaria 298/2026/1) adds granular rate boxes, margin-scheme and VAT-group fields. 

• Filing frequency: SAF-T Billing monthly (by the 5th of the following month); SAF-T Accounting annual (from FY2027, due 2028); on-demand SAF-T during audits. 

8.3. Digital signature & integrity 

• Per-document integrity is guaranteed by the certified-software hash chain (RSA) under Portaria 363/2010 – each document signs on the previous one. This is distinct from the QES: from 1 January 2027 PDF e-invoices must additionally carry an eIDAS QES/qualified seal from a QTSP; B2G invoices already require a qualified signature/seal. 

8.4. Real-time / near-real-time processing 

• e-Fatura communication is near-real-time/periodic and SAF-T Billing is monthly (by the 5th) – there is no T+0 clearance. AT does not publish binding uptime SLAs for taxpayers; the model does not depend on real-time platform availability to issue invoices. 

Sources: InvoiceDataExtraction – four SAF-T file types  |  VATupdate – SAF-T structure  |  VATupdate – Portaria 298/2026/1 

9. Correction of Errors in E-Invoices and E-Reporting

9.1. E-invoice corrections 

• Corrections are made through corrective documents – credit notes (notas de crédito) and debit notes (notas de débito) – issued by certified software, not by editing the original. 

• A corrective document must reference the original invoice, state the reason/nature of the correction and the corrected amounts, and carry its own ATCUD/QR (and, from 2027, QES on PDF). 

• The corrective document flows through e-Fatura and the SAF-T Billing file like any other document. 

9.2. E-reporting corrections 

• SAF-T Billing errors are corrected by re-submitting a corrected file/document within the monthly cycle; VAT-return errors are corrected via a replacement/substitution periodic VAT return (declaração de substituição). 

• Timelines follow ordinary VAT rules; late or incorrect corrections may attract RGIT penalties (chapter 14). There are no separate stand-alone correction forms beyond the standard documents/returns. 

Sources: EDICOM – credit/debit notes as B2G corrective docs  |  InvoiceDataExtraction – SAF-T corrections & deadlines 

10. Transmission & Workflow

10.1. Central platform 

• E-reporting hub: e-Fatura / Portal das Finanças, operated by the Autoridade Tributária e Aduaneira (AT). B2G platform: FE-AP (Fatura Eletrónica na Administração Pública), operated by eSPap. 

10.2. Transmission channels 

• e-Fatura reporting: direct manual entry on the portal, web-service/API upload, or monthly SAF-T Billing file upload (produced by certified software). 

• B2G: FE-AP web portal, WebServices, AS2, the “Microportal” for low-volume suppliers, and Peppol access points. 

10.3. Accredited service providers / certified intermediaries 

• Software must be AT-certified (the certified-software list is public); there is no separate mandatory “accredited PDP” layer as in France. Providers/intermediaries may transmit on the taxpayer’s behalf. From 2027, QES certificates must come from an EU-listed QTSP. 

10.4. Interoperability 

• FE-AP is Peppol-capable for cross-border/interoperable B2G exchange; e-Fatura interconnects with the VAT-return pre-fill engine. Where a public recipient is not reachable via FE-AP, an alternative channel is agreed bilaterally (EDI, WebService, upload). 

10.5. Deadlines & timing 

• Invoice issuance: within 5 business days of the supply (Article 36 CIVA). 

• e-Fatura communication / SAF-T Billing: by the 5th of the month following issuance. 

• Periodic VAT return: monthly regime by the 20th (2nd month following); quarterly regime by the 20th (2nd month following the quarter) – payment shortly after. 

Sources: EDICOM – eSPap/FE-AP channels (AS2/WebServices)  |  Invoice Navigator – FE-AP, Microportal, Peppol  |  VATupdate – 5-day issuance / deadlines 

11. Self-Billing

• 11.1. Permitted: Yes – self-billing (autofaturação) is allowed under Article 36 CIVA and DL 28/2019. 

• 11.2. Platform/reporting: Self-billed documents must be issued by certified software and reported – there is a dedicated SAF-T Self-Billing (S) file / e-Fatura communication (no clearance). 

• 11.3. Authorisation: Requires a prior written agreement between supplier and acquirer, including an acceptance procedure (express or tacit) for each document; documents typically issued in a dedicated series. 

• 11.4. Content: All Article 36 CIVA content applies (dates, both NIFs, taxable amount, rate, VAT or exemption basis). 

• 11.5. Notation: The mandatory mention “autofaturação” must appear; a dedicated document series/flag identifies self-billed documents in SAF-T. 

• 11.6. Foreign buyers: The supplier must be established/registered for VAT in Portugal; arrangements with parties lacking a Portuguese NIF are constrained accordingly. 

• 11.7. Buyer-side validation: The supplier’s acceptance mechanism defined in the agreement governs approval; getting the formalities wrong can compromise the input-VAT deduction. 

Sources: EasyFin – self-billing legal framework & steps  |  SAP – SAF-T Autofaturação (S) file 

12. Triangulation & Special Scenarios

• 12.1. Triangulation: Invoices issued by a Portuguese-registered intermediary are produced by certified software with ATCUD/QR and reported in SAF-T Billing; simplified triangulation carries the reverse-charge mention and feeds the recapitulative (EC Sales) reporting. 

• 12.2. Chain transactions: Each Portuguese-registered leg documents and reports its own invoice; correct allocation of the transport/zero-rating is reflected in the invoice annotations and SAF-T. 

• 12.3. Cross-border reverse charge: Outbound reverse-charge invoices carry the “IVA – autoliquidação” / reverse-charge mention; inbound reverse-charge from foreign suppliers is accounted for by the Portuguese buyer in the VAT return (and captured via e-Fatura classification). 

• 12.4. Zero-rated & exempt supplies: Exports and intra-EU supplies are shown at 0%/exempt with the legal exemption basis; the SAF-T tax table and the revised VAT return provide dedicated codes/fields. 

• 12.5. Local nuances: VAT groups (Lei n.º 62/2025, from 1 July 2026) file a consolidated return via the dominant company; fiscal representatives act for non-residents; domestic construction/scrap reverse charge and margin schemes have specific mentions; autonomous regions (Madeira 22%/16% Azores) apply different rates. 

Sources: VATupdate – VAT groups & return overhaul  |  VATupdate – Comprehensive VAT Guide 2026 

13. Archiving & Retention

• 13.1. Central archiving: e-Fatura holds the reported invoice data, but this does not relieve taxpayers of their own archiving obligation – both issuer and recipient must archive. 

• 13.2. Format: Documents must be kept in a way that guarantees integrity, authenticity and readability; structured/original electronic form is preferred, and paper may be digitised and the originals destroyed under DL 28/2019 (value-blind). 

• 13.3. Retention period: 10 years – Article 52 CIVA (mirrored in Article 123 CIRC and Article 40 Código Comercial). The period runs from the end of the civil year of the transaction. 

• 13.4. Storage location: Electronic archiving within the EU is accepted; storage must remain accessible to AT. Offshore storage outside the EU requires the usual safeguards/accessibility (and, in practice, notification/authorisation considerations). 

• 13.5. Integrity/authenticity/readability: Ensured via certified-software hash chain, sequential storage, checksums and backups; digitised copies carry the same evidentiary value (valor probatório) as originals. 

• 13.6. Audit accessibility: Archived documents and SAF-T files must be produced to AT on demand; AT also has the reported e-Fatura/SAF-T data for cross-checking. 

Sources: Descodify – 10-year retention (Art. 52 CIVA) & paperless  |  Rydoo – Portugal paperless requirements  |  EDICOM – 10-year archiving (issuer & recipient) 

14. Penalties & Enforcement

• 14.1. Grace/transitional: The only current transitional relief is the PDF-without-QES tolerance to 31 December 2026 and the SAF-T Accounting deferral. Existing certified-software/ATCUD/QR/SAF-T obligations are fully enforceable. 

14.2. Penalties for non-compliance (RGIT) 

• Use of non-certified software: fines commonly cited at €3,000–€18,750 per infraction. 

• Failure to issue/late issuance, missing ATCUD/QR, late or omitted SAF-T Billing / e-Fatura communication, incorrect invoices, and archiving breaches are contra-ordenações under the RGIT (Regime Geral das Infrações Tributárias, Lei n.º 15/2001). 

• Reported maximum around €22,500 per infraction; intentional conduct is penalised more severely than negligence, and serious cases can constitute tax offences. 

14.3. Amounts & escalation 

• Coimas are set in bands (fixed amounts and, for some breaches, proportional to the tax at stake) under Articles 23–31 RGIT, with aggravation for repeat/intentional conduct and mitigation for voluntary regularisation (Art. 29–32). 

14.4. Article references & official sources 

• RGIT (Lei n.º 15/2001) – general infractions regime; specific invoicing/SAF-T breaches under the RGIT and CIVA. See the RGIT index on Portal das Finanças. 

Sources: RTC – non-certified software fines €3,000–€18,750  |  Zunapro – up to €22,500 per infraction (RGIT)  |  Portal das Finanças – RGIT 

15. Pre-Filled VAT Returns

• 15.1. Availability: Yes – Portugal offers pre-filled periodic VAT returns via IVA Automático+, live for operations from 1 July 2025 (building on IVA Automático since 2020). 

• 15.2. Fields & source: Output and deductible VAT boxes are pre-filled from invoices issued on the Portal and invoices communicated to AT via e-Fatura, provided the taxpayer classifies all purchase invoices where it is the acquirer. Taxpayers still review, complete and submit. 

• 15.3. Plans/expansion: Portaria n.º 298/2026/1 (16 July 2026) restructures the return to enable more granular automatic pre-filling; most changes apply from periods beginning on/after 1 July 2027 (VAT-group and Housing-Package blocks from 1 July 2026). 

• 15.4. Dependency: Pre-filling depends directly on e-Fatura/SAF-T data quality and on taxpayer classification of received invoices. 

• 15.5. ViDA alignment: The direction (pre-filled returns from transaction data) is consistent with ViDA’s simplification aims, though ViDA does not itself mandate pre-filled returns. 

Sources: AT – IVA Automático+ (from 1 July 2025)  |  VATupdate – Portaria 298/2026/1 pre-fill overhaul 

16. Readiness for VAT in the Digital Age (ViDA)

• 16.1. Position vs ViDA: As an EU Member State, Portugal is aligned with ViDA on B2G/EN 16931 and already reports transaction data (SAF-T/e-Fatura), but it has not yet legislated a domestic B2B DRR/e-invoicing mandate. It is therefore ahead on reporting infrastructure but behind on structured B2B e-invoicing. 

• 16.2. Alignment of national system: CIUS-PT is EN 16931-based and Peppol-compatible, which eases future DRR alignment. Gaps: no domestic structured B2B format obligation and a SAF-T-based (rather than EN-invoice-based) reporting flow that may need adjustment for the ViDA intra-EU DRR. 

• 16.3. Cross-border digital reporting: From 1 July 2030, intra-EU B2B transactions must be reported under ViDA DRR (replacing EC Sales Lists). Portugal will need to channel this data to the EU exchange; the FE-AP/Peppol and e-Fatura stack are a plausible foundation. 

• 16.4. Implications for business: Businesses building on certified software + EN 16931/Peppol/CIUS-PT are broadly future-proofing; the main additional step will be structured cross-border B2B reporting from 2030 and domestic alignment by 2035. Early adopters of structured/Peppol flows gain a head start. 

Sources: e-invoice.app – ViDA milestones on PT timeline  |  e-invoice.app – Portugal guide (model/standard)  |  VATcalc – ViDA DRR 2030 

17. Impact on SMEs and Startups

• 17.1. Phased onboarding: B2G extended to SME/micro suppliers from 1 January 2026, with PDF tolerated to 31 December 2026; QES from 2027. No separate B2B onboarding schedule (no B2B mandate). 

• 17.2. Government support & free tools: AT provides the e-Fatura portal, the Portal das Finanças free invoicing/reporting tools, the Microportal for low-volume B2G suppliers, the certified-software list, FAQs, leaflets and manuals. 

• 17.3. Simplified regimes/thresholds: Simplified invoices for small values; small taxpayers below defined turnover thresholds may fall outside certified-software obligations in narrow cases; VAT registration threshold €15,000 (from 2025). 

• 17.4. Subsidies: No dedicated national e-invoicing grant/tax-credit scheme is currently in force (not legislated); general digitalisation supports may apply. 

• 17.5. Compliance costs: One-off: certified software/ERP integration, ATCUD/QR set-up, and (for 2027) QES certificates and signing workflow; ongoing: software maintenance, QTSP certificate fees and provider fees. 

• 17.6. Cash-flow/operational benefits: Pre-filled VAT returns, reduced manual entry, elimination of paper, earlier error detection and faster reconciliation. 

• 17.7. Burden vs simplification: Initial set-up burden is real, but the mature e-Fatura/SAF-T stack delivers long-run simplification (automatic returns, digitised archiving). 

• 17.8. Market impact: Strong certified-software ecosystem; advantages for early Peppol/structured adopters; interoperability generally good via CIUS-PT/Peppol. 

• 17.9. Official assessments: The Ministry of Finance attributes a material reduction in VAT fraud to e-Fatura; no specific negative SME-readiness assessment has been published for the 2026–2027 steps. 

Sources: Fiskaly – tools & obligations for SMEs/POS  |  ERP Implementation – costs & ERP requirements  |  VATupdate – €15,000 threshold (VAT Guide 2026) 

18. Official References & Sources

18.1. Government portals 

• Portal das Finanças (AT)  – tax authority portal. 

• e-Fatura  – invoice reporting / consumer invoices / software producers. 

• SAF-T (PT) area  – SAF-T files, SVAT seal, manuals. 

• eSPap / FE-AP (B2G)  – public-administration e-invoicing. 

18.2. Legislative texts 

• Diário da República  – DL 28/2019, DL 111-B/2017, Lei 73-A/2025 (OE2026), Portarias 363/2010, 195/2020, 321-A/2007, 221/2017, 298/2026/1. 

• RGIT (Lei 15/2001) index  – penalty regime. 

18.3. Technical specifications 

• EC – eInvoicing in Portugal (CIUS-PT/EN 16931) 

• SAP Help – SAF-T Self-Billing structure (reference) 

18.4. Tax authority publications 

• AT – IVA Automático+ leaflet  |  AT – IVA Automático announcement 

18.5. Advisory & technology analysis 

• KPMG TaxNewsFlash (Dec 2025)  |  Fonoa – QES delay to 2027  |  Sovos/VATcalc – SAF-T (PT) 

• EDICOM – Portugal e-invoicing/e-reporting  |  RTC – e-invoicing Portugal 2026  |  Dynatos  |  Meridian 

• VATupdate – Portugal country page & VAT Guide 2026  |  VATupdate – QES delay 

18.6. Link status 

• All links verified accessible as at 7 August 2026. Legislative texts should always be cross-checked against the consolidated versions on diariodarepublica.pt, as budget laws periodically amend dates. 

19. Summary & Key Takeaways

• 19.1. Scope: No B2B/B2C structured e-invoicing mandate; B2G structured e-invoicing mandatory (SME/micro from 2026). Every invoice needs certified software + ATCUD + QR + monthly SAF-T Billing. Non-residents VAT-registered in Portugal are in scope since 2023. 

• 19.2. Format: B2G: CIUS-PT (UBL 2.1 / CEFACT CII, EN 16931). B2B/B2C: paper/PDF/structured all valid, but PDF needs a QES from 1 January 2027. 

• 19.3. Timeline: QR 2022 – ATCUD & non-residents 2023 – B2G SME/micro Jan 2026 – PDF-without-QES ends 31 Dec 2026 – QES Jan 2027 – SAF-T Accounting FY2027 (due 2028). 

• 19.4. How it works: Post-audit / decentralised model – issue → exchange directly → report to e-Fatura + monthly SAF-T Billing; integrity via certified-software hash chain, ATCUD and QR. No per-invoice clearance. 

• 19.5. Key obligations: Certified software; ATCUD/QR on every document; 5-day issuance; SAF-T Billing by the 5th; corrections via credit/debit notes; 10-year archiving. 

• 19.6. Main risks: RGIT penalties (non-certified software €3,000–€18,750; up to ~€22,500 per infraction), SAF-T rejection/late filing, loss of input-VAT deduction (esp. self-billing formalities), and archiving breaches. 

• 19.7. SME implications: Free AT tools and a mature certified-software market lower barriers; costs centre on software/ERP integration and 2027 QES certificates; benefits include pre-filled VAT returns and paperless archiving. 

• 19.8. ViDA readiness: Strong reporting base and EN 16931/Peppol-ready B2G; gap is a domestic B2B DRR/e-invoicing obligation, to be aligned with ViDA intra-EU DRR (2030) and domestic alignment (2035). 

19.9. Critical dates & next steps 

• Now–2026: ensure AT-certified software, correct ATCUD series communication, QR on all documents, timely SAF-T Billing, and classify received invoices for IVA Automático+. 

• By 31 Dec 2026: prepare to replace unsigned-PDF issuance – procure QES certificates from an EU QTSP and integrate qualified signing/sealing (or move to structured/EDI). 

• 2027–2028: apply QES on PDF e-invoices; prepare annual SAF-T Accounting for FY2027 (first file 2028); adapt to the restructured VAT return (Portaria 298/2026/1). 

• 2030/2035: plan for ViDA cross-border B2B DRR and eventual domestic alignment; consolidate on EN 16931/Peppol/CIUS-PT. 

End of analysis. This document is for information only and does not constitute tax or legal advice; verify against consolidated legislation before acting.