Austria VAT number: format and validation

By Remco from Avatcado

Format

AT followed by the letter U and 8 digits. The local term is Umsatzsteuer-Identifikationsnummer (UID, German).

Pattern: /^U\d{8}$/

  • Always begins with U after the AT prefix; there is no all-digit Austrian VAT number
  • The UID is separate from the domestic Steuernummer; small businesses under the Kleinunternehmer exemption often have no UID until they request one for intra-EU trade

Example of a registered number: ATU14189108

Check digit

Austria VAT numbers carry a check digit (Weighted MOD 10): The last digit is derived from the first seven using alternating weights with digit sums and the formula (96 - sum) mod 10.

Check a Austria VAT number

Validated live against the Bundesministerium fuer Finanzen (BMF) (official register).

Enter a VAT number to see the live API response

Validate via API

The same validation as an API call, with the example number above:

curl "https://api.avatcado.com/v1/validate?vat_number=ATU14189108" \
  -H "Authorization: Bearer avat_live_your_api_key"
import Avatcado from "@avatcado/node";

const avatcado = new Avatcado("avat_live_your_api_key");
const { data, error } = await avatcado.vat.validate({
  vatNumber: "ATU14189108",
});

if (data?.data.valid) {
  console.log(`Registered: ${data.data.company?.name}`);
}

Free tier includes 500 validations per month. Get an API key or read the API documentation.

Frequently asked questions

What is the VAT registration threshold in Austria?

Since 1 January 2025 the Kleinunternehmer exemption covers annual turnover up to EUR 55,000 gross (previously EUR 35,000 net). A single overshoot of up to 10 percent keeps the exemption until year end.

How do I look up an Austrian UID?

There is no public national register. Austrian businesses confirm a partner's UID via FinanzOnline (stage 1 and 2 confirmation); everyone else uses the EU VIES tool or a validation API.

Related guides

VAT rate in Austria

The standard VAT rate in Austria is 20%. Reduced rates: 13%, 10%, 4.9%. See all Austria VAT rates.

Sources