VAT ID

A VAT ID shows that a customer buys as a business and where that business is. That is what lets an invoice between two EU countries go out under reverse charge. As of 1 October 2026, in Austria:

• On reverse-charge invoices: the VAT IDs of both sides and the note that the tax liability passes to the customer.
• On domestic invoices over €10,000: the customer’s VAT ID as well, when an Austrian business invoices another business (§ 11 Abs. 1 Z 3 UStG).
• Your own VAT ID: on invoices for taxable supplies in Austria.
• Checking: Austrian businesses check the VAT ID of a business in another EU country through FinanzOnline (level 1: valid or not; level 2: valid for this name and address) or the European Commission’s online check (VIES), and keep the confirmation.

Example

A club in Vienna books [Artist A] from Hamburg and sends its VAT ID (UID-Nummer), ATU12345678, with the company name and address before the contract. The artist side checks it and invoices €2,500 net under reverse charge. Without a valid ID on file, the artist side has no proof that the club books as a business.

What to watch for

• Not VAT IDs: numbers starting with EU, IM or IN. They can’t be checked either.
• Business only. A VAT ID is for business purchases, never for private ones.

This is general information, not tax advice. Check your case with a tax adviser.