Short answer
A failed VIES check tells you one thing only: the number as entered could not be confirmed as valid at the moment you asked. It is not a finding that the customer is a private consumer, and it is not a finding that the customer has no business status.
Those are two different questions, and EU VAT law keeps them apart:
- Validation is the process in Article 18(1)(a) of the Implementing Regulation, by which a supplier may rely on a confirmed number to treat the customer as a taxable person.
- Status is the underlying legal question under Articles 9 to 13 and Article 43 of the VAT Directive: is this person carrying out an economic activity?
A number can fail validation while the customer is unquestionably a business — a recently registered company, a number not yet propagated, a transposition error, or a national system that is temporarily unavailable. Conversely, a valid number does not oblige you to ignore contrary information.
The practical answer is to stop the transaction from completing on a reverse-charge basis, ask the customer to confirm the number, and fall back to charging VAT if it cannot be confirmed.
What VIES actually is
VIES is the interface to the exchange of registration data between Member States under the administrative-cooperation rules. Article 18(1)(a) of the Implementing Regulation ties the supplier's entitlement to that confirmation mechanism:
"where the customer has communicated his individual VAT identification number to him, and the supplier obtains confirmation of the validity of that identification number and of the associated name and address in accordance with Article 31 of Council Regulation (EC) No 904/2010" —
Two points in that text are routinely missed. The confirmation extends to the associated name and address, not only the number. And the confirmation is of validity at the time of the query — the underlying registers are national, and each Member State controls what it returns.
A VIES response is therefore evidence, captured at a moment in time. Store the full response and its timestamp, not a boolean.
A failed check is not evidence of consumer status
This is the central error. Article 18(2) permits a supplier to treat an EU customer as non-taxable where the supplier "can demonstrate that the customer has not communicated his individual VAT identification number". The trigger is the customer not communicating a number — not a number that was communicated and then failed a lookup.
Where a number has been given but cannot be validated, you are in neither limb of Article 18. You do not have the Article 18(1)(a) entitlement to treat the customer as taxable, and you do not have the Article 18(2) route to treat them as a consumer on the basis that no number was supplied.
There is one important qualification for digital businesses. For telecommunications, broadcasting and electronically supplied services, and for virtually attended activities under the second subparagraph of Article 54(1), the amended Article 18(2) allows the supplier to treat the customer as non-taxable for as long as no number has been communicated — and to do so irrespective of information to the contrary. That is a safe harbour keyed to the absence of a number, and it is why most SaaS checkouts should default to charging VAT rather than blocking the sale.
Article 18(1)(b): the route when validation is not available
The Implementing Regulation anticipates that a business customer may have no usable number yet:
"where the customer has not yet received an individual VAT identification number, but informs the supplier that he has applied for it and the supplier obtains any other proof which demonstrates that the customer is a taxable person ... and carries out a reasonable level of verification of the accuracy of the information provided by the customer, by normal commercial security measures such as those relating to identity or payment checks." —
This is a real alternative, but it is conditional and evidential. It requires a statement that an application has been made, other proof of taxable-person status, and a documented commercial verification step. It is workable for a negotiated enterprise contract. It is not workable for an automated self-service checkout, which is precisely why automated flows should fall back to charging VAT.
What to do, in order
Re-check the input before anything else. Country prefix duplicated into the body of the number, spaces and punctuation, and confusion between a domestic tax reference and the EU VAT identification number account for a large share of failures. Some Member States issue a separate identifier for intra-EU transactions that must be specifically activated.
Distinguish a negative answer from no answer. A response stating the number is invalid is different from a timeout or a national system being unavailable. Retry the latter; do not treat it as a negative.
Ask the customer. Give them the exact number you queried and the date. If the registration is new or has recently changed, the customer is the only party who can resolve it.
Decide the transaction on the evidence you have. If you cannot validate and cannot satisfy Article 18(1)(b), charge VAT. For a B2C digital service that means destination VAT, reported through the One Stop Shop where you use it. Charging VAT and correcting later is recoverable; failing to charge VAT on a supply that turns out to be domestic or B2C is a liability you carry yourself.
Do not simply proceed on the number as given. Article 196 shifts liability to the customer, but your entitlement to invoice without VAT rests on the Article 18 evidential position. If that position is absent, the exposure returns to you.
Correcting the position afterwards
If the customer later produces a valid number covering the date of supply, you can normally correct the treatment: issue a corrected invoice, refund the VAT charged, and adjust your return. Where the original supply was declared through OSS, the correction goes into a subsequent OSS return under the amendment mechanism, which runs for three years from the date the original return was due.
Where the customer never resolves the position, the VAT you charged stands. Say so in your terms, so the commercial expectation matches the legal one.
A note on the goods analogy
Sellers sometimes reason from the case law on intra-Community supplies of goods, where the Court of Justice has held that substantive conditions prevail over formal ones and a missing customer VAT number does not automatically defeat an exemption. That line of authority concerns the exemption for supplies of goods, and the legislature has since tightened the position by making the customer's identification a substantive condition in that context.
It does not transpose neatly to the service rules. For services, the question is not exemption but place of supply, and the evidential framework is the one in Articles 17 to 19 of the Implementing Regulation. Reason from those Articles.
Operational checklist
- Validate at checkout and again at invoicing for recurring subscriptions.
- Store the full validation response with a timestamp, not a pass/fail flag.
- Separate "invalid" from "service unavailable" and retry only the latter.
- Never infer consumer status from a failed check.
- Default automated checkouts to charging destination VAT where no valid number is held.
- Reserve the Article 18(1)(b) route for negotiated contracts where you can document the proof and the verification.
- Have a documented correction path, including the OSS amendment window.
Conclusion
Treat VIES as a documented evidence step, not a gate that classifies your customer. Validation failure removes your entitlement to invoice without VAT; it says nothing about whether the customer runs a business.
The safe operational posture is to charge VAT whenever you cannot evidence taxable-person status, and to correct afterwards if the customer resolves the registration. For electronically supplied services, the amended Article 18(2) safe harbour makes that posture not merely safe but expressly provided for.
Sources
This article provides general legal information, not advice for a specific matter. Laws, facts and procedural deadlines may change the result. Follow the linked primary sources and obtain local advice before acting.