Check an Austrian VAT number: how to tell whether a UID is valid

How the Austrian UID is built

An Austrian UID starts with ATU followed by eight digits, for example ATU12345678. The tax office assigns it on application. Other EU countries have their own formats: Germany uses DE with nine digits, Italy IT with eleven.

The UID is neither the register number nor the tax number. The register number has up to six digits and a check letter; the tax number is an internal number of the tax office.

Checking through VIES

The European Commission runs VIES, the VAT Information Exchange System. Enter country and number and VIES tells you whether the number is valid. For some countries it also shows name and address; for Austria only the validity.

Austrian businesses can also use the confirmation procedure in FinanzOnline: level 1 checks validity only, level 2 checks the partner's name and address as well.

Why the UID is not in the company register

The company register holds company name, register number, seat, legal form, capital and representation. The UID belongs to tax law and is managed by the tax office, so it appears neither in the register extract nor on firmenbuchdaten.at.

Both together make the check: the UID tells you that your partner is registered for VAT. The register number tells you that the company exists, who represents it and whether its annual accounts have been filed.

When to check the UID

A valid partner UID is a condition for VAT-free intra-EU supplies. Check it:

• Before the first invoice to a business in another EU country
• Whenever the partner's name or address changes
• At regular intervals in ongoing relationships, and keep a record of the result