Portugal E-Invoicing — Customer Setup Guide

Who this is for: The finance/accounting contact at your organisation who will set up e-invoicing. What it covers: The steps you need to complete so that invoices issued from the Lavanda PMS are legally compliant in Portugal.

Lavanda will configure our side of the integration separately and will ask you only for the details listed in the “What we’ll need from you” section below. Everything else in this guide is done by you, in your own tax-authority account and in the Invopop portal.

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1. The big picture (read this first)

In Portugal, every invoice and credit note must be certified: it needs a tax-authority-registered number series, a digital signature, an ATCUD code and a QR code, and it must be reported to the Autoridade Tributária e Aduaneira (the tax authority, “AT”).

Lavanda does not do this directly — we use Invopop, a certified provider, to sign, number and produce the compliant PDF. For this to work, you need to connect your official tax-authority credentials and register your invoice number series. That is what this guide walks you through.

You’ll work in two places:

Where	What you do there	Link
Portal das Finanças (the AT’s own website)	Create a dedicated user that Invopop uses to talk to the tax authority	portaldasfinancas.gov.pt
Invopop AT Portugal Supplier Portal	Save those credentials, register your number series, and download your SAF-T report	at-pt.invopop.com/portal

Full Invopop reference: AT Portugal supplier guide · Prerequisites · Portugal FAQ

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2. What we’ll need from you (before you start)

Have these ready — they must be accurate and complete, as they appear on your legal invoices:

• Exact legal business name
• Portuguese Tax ID (NIF)
• Full registered business address (street, number, postal code, locality)
• A dedicated email address for your Invopop Supplier Portal login (this must be unique to your organisation — it becomes your portal login)
• Mandatory registration details that appear on invoices: share capital, registered office, and commercial registration details

Lavanda needs all of the information above to properly configure your supplier in Invopop — please send it to us.

You also need to be able to log in to the Portal das Finanças with your company’s tax-authority access (NIF + password, or Chave Móvel Digital). Please confirm this early — nothing else can be done without it.

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3. The steps you need to complete

Work through these in order. We’ll run a quick test issue with you at the end (Step 6) before you start issuing live invoices.

Step 1 — Log in to the Portal das Finanças

Go to portaldasfinancas.gov.pt and click Iniciar Sessão (Log in). Sign in with your company’s tax-authority credentials.

Step 2 — Create a dedicated user for Invopop

This creates a separate sub-user that Invopop uses to communicate with the AT — your own personal login is never shared.

1. Go to Todos os Serviços → Autenticação de Contribuintes → Gestão de Utilizadores (Manage Users).
2. Click Criar Novo Utilizador (Create New User).
3. Give it a recognisable name that includes the building, e.g. “Invopop Lisbon Building”.
4. Grant the WSE permission — “Always required. It allows to register series for any document type.” This is the only permission needed for our setup (we report via the SAF-T report you download, so the real-time submission permissions are not required).
5. Click Submeter (Submit).
6. Carefully save the username and password that are generated — you’ll need them in Step 3, and they are hard to recover.

📖 Reference: Invopop supplier guide — obtaining AT credentials.

Step 3 — Log in to the Invopop Supplier Portal and save your credentials

1. Go to the Invopop AT Portugal Supplier Portal.
2. Enter the email address we registered for you; you’ll receive a one-time code by email to log in.
3. Open the Credentials section, enter the AT username and password from Step 2, and click Save. The AT username is usually your Tax ID followed by /1 — for example 517955290/1.

📖 Reference: Invopop supplier guide — complete registration in the Supplier Portal.

Step 4 — Register your number series (FT and NC)

Still in the Supplier Portal, open the Series section and click + Register to add one series per document type — one for invoices (FT) and one for credit notes (NC). For each series:

• Set the sequence type to Normal.
• Optionally add a short prefix if you want one to appear in the number.

The resulting document numbers then look like this:

• Invoices: FT-000000001 — or FT-PREFIX-000000001 if you add a prefix.
• Credit notes: NC-000000001 — or NC-PREFIX-000000001 if you add a prefix.

Registering the series here also communicates it to the AT (that is what the WSE permission from Step 2 is for). Only one series per document type is supported, and the sequence type cannot be changed after the series is registered.

📖 Reference: Invopop supplier guide — series management, naming & types.

Step 5 — Download and submit your SAF-T report to the AT (ongoing)

Invopop records every issued document for reporting, but it does not send SAF-T to the tax authority for you. On the schedule required by the AT, you:

1. In the Invopop Supplier Portal, open the SAF-T PT section.
2. Enter the date range for the period and click Generate — this produces a SAF-T PT file containing the documents issued in that period.
3. Download the file and upload it to the AT via the Portal das Finanças (there is no automatic submission — this is a manual upload).

📖 Reference: Invopop AT Portugal guide · Portugal FAQ.

Step 6 — Confirm back to Lavanda

Let us know once your credentials are saved and a series is registered for both FT and NC. We’ll then run a test issue with you to confirm everything is connected correctly.

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4. What the Lavanda + Invopop e-invoicing does (so you know what to expect)

Document types issued through the compliant flow:

• Invoices — Fatura, series prefix FT. (Corrective invoices are also treated as invoices, i.e. FT.)
• Credit notes — Nota de Crédito, series prefix NC.

How a document behaves in the PMS:

• A document moves Draft → Issued once it comes back certified. It doesn’t go through an “Issuing” state.
• If an invoice is missing any required information, it goes back to Draft and is flagged with “issue errors”. It will not be resubmitted until you (the PMS user) fix the document. Once corrected, it can be issued again.
• To set up your number sequences you must first sign in to the Invopop AT Supplier Portal and add your AT user’s credentials (see Step 3). Once a series is registered, Invopop manages the running numbers automatically — numbers look like FT-000000001 for invoices and NC-000000001 for credit notes (or FT-PREFIX-000000001 / NC-PREFIX-000000001 if you added a prefix). You never assign numbers yourself (Portuguese law does not allow pre-assigning them).
• The final compliant PDF (with signature, ATCUD and QR code) is produced by Invopop.

Reporting to the AT (important — this is your responsibility):

• Invopop does not send SAF-T automatically. You download the SAF-T PT report from the Invopop Supplier Portal and upload it to the AT’s Portal das Finanças on the required schedule (see Step 5).

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5. Your go-live checklist

• I can log in to the Portal das Finanças
• AT user created with the WSE permission (named after the building)
• AT username/password saved into the Invopop Supplier Portal Credentials
• Normal series registered for invoices (FT) and credit notes (NC)
• I know how to generate and download the SAF-T PT report and upload it to the AT
• Confirmed back to Lavanda

Once every box is ticked, you’re ready to issue live, compliant invoices from the PMS.

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Based on Invopop’s AT Portugal supplier and prerequisites guides (docs.invopop.com/guides/pt-at-supplier and /pt-at), aligned with Lavanda’s e-invoicing implementation.