VIES or the VAT Information Exchange System, is an electronic channel of transmitting information related to VAT registration of companies registered in the European Union. The E.U. requires that for goods and services procured within the E.U., VAT must be paid only in the member state where the purchase resides. This validation of the VAT numbers is done through VIES.

VIES is not a database, but a search engine. It is connected directly to each member state tax office. When a search is done, VIES queries the database of the specified country.

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