VIES

What it means

VIES is the European Commission’s system for checking the validity of VAT IDs issued in member states. It answers one question: is this number valid today in that country.

The same system carries the exchange of EC sales list data between tax administrations. That is how a supply exempt at the supplier is matched against an acquisition declared by the customer.

VIES says nothing about whether a partner is reliable, genuinely trading or creditworthy - only whether the number exists and is active. Some countries show the name and address with the number and others do not, so a match with the order details sometimes has to be evidenced another way.

How it works in practice

The check is made at the time of supply, not once when the contract is signed - a registration can be cancelled at any time. The result is kept: either a confirmation with a consultation number, or at least a dated screenshot.

For an intra-EU supply the customer’s valid VAT ID is one of the conditions for VAT exemption. For sales to consumers through OSS it does not apply, since the customer has no number.

For a new EU customer we check the number before the first invoice and compare the name and address with the order. For regular customers we repeat the check in bulk before each filing, so an invalid number is caught before the tax administrator catches it in a cross-check.

What to watch out for

The system sometimes reports a member state’s database as temporarily unavailable - that is not the same as an invalid number, and the check must be repeated. And a valid number alone is not enough: without evidence of transport the exemption fails.

If the customer had no valid number at the time of supply, the supplier should have charged Slovak VAT. The tax administrator assesses it on the supplier with interest or a penalty, and recovering the difference from a customer who has already paid the net amount is very hard after the fact.