Invoicing EU Clients from Portugal: VIES, Reverse Charge, and What Your Invoice Must Show

A client in Germany sends you their VAT number. You add it to the invoice, mark VAT at zero, include a line about reverse charge, and send it. Most of the time, this works fine. Sometimes you've skipped the step that determined whether you were allowed to do it.

The reverse charge on EU B2B services is real and does what people expect: VAT liability shifts to your client, you invoice at zero, nothing to remit to Portugal. But there is a gate before that mechanism applies. The client's VAT number must be confirmed as active in VIES at the time you issue the invoice.

What VIES checks, and why it matters

VIES stands for VAT Information Exchange System. It is the EU database where each member state publishes active VAT registrations for cross-border verification. You enter a VAT number with the country prefix, and VIES returns one of two results: the number is active, or it is not.

Active means the registration is current in the foreign member state's system. Not active means it is wrong, expired, or for some reason not showing as a live registration. Companies dissolve. VAT registrations lapse. Clients sometimes give you last year's format or a number that was active when they first registered you as a supplier and has since changed.

The reverse charge is only permitted when VIES confirms the number as active. A client who tells you they are VAT-registered, who sends you what looks like a correct number, is not the same as a VIES-confirmed registration. If VIES returns invalid, or if a client has no EU VAT number to provide, you are not permitted to invoice without VAT. You charge Portuguese VAT instead, currently 23% for most services.

This is the step that gets skipped in informal invoicing setups: VIES is checked once, or not at all, and the assumption is that anything claiming to be a business client qualifies.

What your invoice must say

Assuming VIES confirms the number as active, two phrases must appear on the invoice. Both. Not one or the other.

"IVA - autoliquidação" is the Portuguese statutory reference. It comes from Art. 6.º n.º 6 alínea a) do CIVA, a contrário: the place-of-supply rule that puts an intra-EU B2B service outside Portuguese VAT, so the liability lands on your client instead. In certified invoicing software, exemption code 115 maps to this. The phrase must appear on the invoice, not just be implied by a zero VAT line, and it stays in Portuguese whatever language the rest of the invoice is written in.

(Art. 2(1)(g) CIVA is a different rule that often gets quoted here by mistake. It is the mirror case: it makes you liable for the VAT when you buy services from a foreign supplier like AWS or Stripe. It is not the basis for the mention on an invoice you issue.)

"Reverse charge" is the EU-level reference, required by Art. 226(11a) of the EU VAT Directive. It must appear on the invoice alongside the Portuguese reference. Your German client's accounts-payable process needs this phrase to book the invoice correctly and apply their domestic reverse charge. The Portuguese AT reference satisfies your compliance; the EU Directive reference is what makes the invoice work for your client.

Beyond those two phrases, the client's VAT number must include the two-letter country code: DE for Germany, FR for France, NL for the Netherlands, and so on. Not just the digits. DE289794913, not 289794913. The country prefix is part of the VAT number format defined by the Directive, and it is what VIES uses to route the lookup to the right member state.

The Declaração Recapitulativa

Separate from the invoice itself, there is a periodic filing obligation: the Declaração Recapitulativa. It is a report listing each EU business client, their VAT number, and the total amount you invoiced them in the period.

What catches people is when this starts: from your first EU B2B invoice. Not when you cross the Art. 53 threshold. Not when your turnover reaches some other level. From the moment you invoice your first EU business client.

The Art. 53 exemption governs whether you charge VAT. The recap statement is tied to the supply itself, and its obligation does not wait for any revenue threshold. Submission is through the AT portal.

Your filing cadence follows your VAT cadence, which for most freelancers is quarterly. A common piece of misinformation says the cadence switches to monthly once your EU sales pass €50,000. That threshold is real, but it counts intra-EU sales of goods only. Services sit outside the count entirely, so if you sell services you stay on your VAT cadence no matter how much you invoice. The threshold matters if you ship goods into the EU, and not otherwise.

If you have been invoicing EU business clients and have not been filing the recap statement, the correction path depends on how many invoices are involved and over what period. Worth going through with a contabilista certificado before you start filing retrospectively.

When VIES returns invalid

VIES failures are not always definitive. National databases do not always update in real time. A newly registered client might not appear in VIES for a few days. The VIES system itself occasionally times out rather than returning a clear result.

The practical rule: you cannot apply reverse charge to an invoice until VIES confirms the number as active. If you cannot get a confirmation at the time of invoicing, you wait. Most invoicing software built for EU B2B work runs the VIES check during invoice creation and blocks reverse charge if confirmation is absent.

If a client's number comes back definitively invalid, the conversation with the client is straightforward: you need a valid EU VAT number to invoice without VAT. If they cannot provide one, the invoice includes Portuguese VAT, which they may be able to recover on their side depending on their situation. You cannot waive the requirement.

How Descodify handles this

A recent fix corrected a gap in how reverse charge was applied. Previously, the system could apply reverse charge based on a stored client profile without re-confirming that the VIES validation was current at invoice time. The fix makes a confirmed VIES result the hard gate: if the client's EU VAT number is not confirmed active in VIES, reverse charge does not apply and the invoice shows why.

This is not a new rule. The VIES validation requirement has been in EU VAT law for years. But it is easy to build a workflow that checks VIES once, saves the result, and assumes it is permanent. VAT registrations are not permanent.

What this looks like in practice

For most freelancers with EU business clients, the workflow is:

Your client provides their VAT number including the country prefix. You look it up in VIES before creating the invoice. VIES confirms active. The invoice shows zero VAT, "IVA - autoliquidação", and "Reverse charge". The client's number appears in full. You file the Declaração Recapitulativa covering that client for the period.

If VIES returns invalid or the client has no number, the invoice includes Portuguese VAT at 23%. The client may need to provide a corrected number, or they pay the VAT and handle recovery on their end.

The mechanism itself is clean. The VIES step is what separates a compliant EU B2B invoice from one that looks right but is not.

Related: Invoicing foreign clients as a solo entrepreneur in Portugal, the full breakdown of document types, cash-basis timing, and the two-step fatura-receipt workflow.

Related: VAT in Portugal for freelancers, when Art. 53 applies and the two triggers that require VAT from invoice one regardless of turnover.

Related: How to invoice a foreign client in English from Portugal, why the AT portal generates Portuguese-only documents even with the interface set to English.