E-invoicing in Portugal: A Complete Guide for Businesses

What is Portugal e-invoicing?

Portugal operates one of Europe's most mature invoice control frameworks, built around two complementary obligations: ATCUD (Código Único de Documento — Unique Document Code) and SAF-T PT (Standard Audit File for Tax). Together, these create a near-real-time reporting trail that the AT (Autoridade Tributária e Aduaneira — Tax and Customs Authority) uses to audit businesses.

Unlike Italy's clearance model, Portugal does not require invoices to be pre-approved before delivery. Instead, businesses must embed an ATCUD code in every invoice (generated using a series validation code obtained from AT), and submit SAF-T PT files monthly. The framework is complemented by mandatory use of AT-certified invoicing software — only software certified by AT may legally issue invoices in Portugal.

The legal basis spans multiple decrees, including Portaria n.º 195/2020 (ATCUD technical specification) and Decreto-Lei n.º 28/2019 (invoicing obligations).

The SAFT-PT + ATCUD format

Portugal's invoice data obligations consist of two components:

ATCUD (per invoice):

• A unique code in the format ATCUD:VALIDATION_CODE-SEQUENTIAL_NUMBER
• The validation code is obtained from AT per invoice series via the AT web service (SeriesRegistration)
• Must appear visually on the invoice and in the SAF-T PT export

SAF-T PT (monthly reporting):

• XML file conforming to the Portuguese SAF-T schema (currently version 1.04)
• Contains all invoices, credit notes, and payment records for the reporting period
• Submitted to AT via the AT portal or directly via API
• Structure: Header, MasterFiles (customers, products, tax table), SourceDocuments (invoices, payments)

Key invoice fields:

• InvoiceNo: sequential number within a series, in format SERIES TYPE/NUMBER (e.g. FT 2025/145)
• InvoiceType: FT (tax invoice), FS (simplified invoice for <EUR 1,000), NC (credit note), ND (debit note)
• TaxRegistrationNumber: Portuguese NIF (9 digits) for supplier and buyer
• ATCUD: required on all invoices from 2023

Who does it apply to?

There is no B2B e-invoicing clearance mandate analogous to Italy — Portugal's model is reporting-based.

Timeline / key dates

• Jan 2019: SAF-T PT mandatory for all VAT-registered businesses
• Jan 2020: Hash-signing of invoices mandatory (QR code on invoices from 2020)
• Jan 2023: ATCUD mandatory on all invoices
• Ongoing: AT regularly updates the SAF-T PT schema and ATCUD technical specification

How Clearvo handles Portugal e-invoicing

Clearvo handles ATCUD series registration with AT, code generation per invoice, QR code embedding, and SAF-T PT file generation for monthly reporting.

Key points:

• Before issuing the first invoice in a new series, Clearvo calls AT's series registration API to obtain the validation code — this is done automatically when you create a new invoice series
• Each invoice receives a sequentially generated ATCUD code stored in Clearvo's database
• At month-end, Clearvo generates a complete SAF-T PT XML file covering all invoices in the period, ready for AT submission
• Clearvo uses AT-certified invoice logic; the generated documents satisfy the InvoiceNo formatting, InvoiceType, and hash-signing requirements

What you send: standard invoice fields plus supplierNif, customerNif, invoiceSeries, and buyerCountry: "PT".

What you get back: the invoice with embedded ATCUD, QR code data, and hash signature.

{
  "invoiceNumber": "FT 2025/00145",
  "invoiceSeries": "FT",
  "invoiceType": "FT",
  "issueDate": "2025-06-01",
  "dueDate": "2025-07-01",
  "currency": "EUR",
  "supplier": {
    "name": "Acme Software Lda",
    "vatNumber": "PT123456789",
    "nif": "123456789",
    "address": {
      "street": "Avenida da Liberdade 200",
      "city": "Lisboa",
      "postalCode": "1250-147",
      "country": "PT"
    }
  },
  "customer": {
    "name": "TechPrime Soluções SA",
    "vatNumber": "PT987654321",
    "nif": "987654321",
    "address": {
      "street": "Rua do Comércio 44",
      "city": "Porto",
      "postalCode": "4000-150",
      "country": "PT"
    }
  },
  "lines": [
    {
      "description": "Subscrição de software — junho 2025",
      "quantity": 1,
      "unitPrice": 1800.00,
      "taxRate": 23,
      "taxCategory": "S"
    }
  ],
  "paymentTerms": "30 dias"
}

Getting started

ATCUD series registration, SAF-T PT generation, and AT submission are documented at clearvo.io/docs. The AT test environment (testefaturacao.at.gov.pt) is supported via the environment: "sandbox" parameter.

Related country guides

• Spain — VeriFactu hash-chain + Peppol B2B mandate
• France — Factur-X PDP model, mandate from September 2026
• Italy — FatturaPA SDI clearance, mandatory since 2019

Frequently asked questions

What is ATCUD and is it mandatory? ATCUD (Código Único de Documento — Unique Document Code) is a mandatory identifier that must appear on every invoice issued by a Portuguese-registered business from 1 January 2023. The code follows the format ATCUD:VALIDATION_CODE-SEQUENTIAL_NUMBER, where the validation code is obtained from the AT (Autoridade Tributária) per invoice series. There is no SME exemption — the obligation applies to all VAT-registered businesses.

When must SAF-T PT be submitted? SAF-T PT (Standard Audit File for Tax — Portugal) must be submitted monthly to the AT via the AT portal. The submission covers all invoices, credit notes, and payment records for the preceding calendar month. The deadline is the 20th of the month following the reporting period. SAF-T has been mandatory for all VAT-registered businesses in Portugal since 2019.

Does Portugal's framework apply to foreign businesses with a Portuguese VAT number? Yes. If your business holds a Portuguese VAT registration, the full obligations apply regardless of where your company is incorporated: ATCUD on every invoice, use of AT-certified invoicing software, and monthly SAF-T PT submission. Foreign businesses with a PT VAT number should ensure their invoicing software is AT-certified before issuing invoices.

What is AT-certified software and why does it matter? Portuguese law (Decreto-Lei n.º 28/2019) requires that invoices be issued by software certified by the AT. Certification confirms that the software meets integrity, sequential numbering, and reporting requirements. Invoices produced by uncertified software are not legally valid for VAT deduction purposes. Clearvo's invoice generation is built to AT certification requirements.

How does Clearvo handle ATCUD series registration? Before issuing the first invoice in a new series, Clearvo automatically calls AT's series registration web service to obtain the validation code for that series. Subsequent invoices in the series receive sequentially generated ATCUD codes. The validation code and sequence counter are stored per series in Clearvo's database, so you never need to manage them manually.