Turkey VKN / VAT Number Validator (GİB e-Fatura)

How Turkish VKN, KDV, and GİB e-Fatura verification works

In the Republic of Turkey (Türkiye), taxation and revenue collection are administered by the Gelir İdaresi Başkanlığı (GİB), an agency of the Ministry of Treasury and Finance (T.C. Hazine ve Maliye Bakanlığı). Every legal entity, joint-stock company (Anonim Şirket — A.Ş.), and limited liability company (Limited Şirket — Ltd. Şti.) is assigned a unique 10-digit Vergi Kimlik Numarası (VKN). For international cross-border trade, customs clearance, and reverse charge invoicing, the international ISO 3166-1 alpha-2 prefix TR is prepended (for example, TR6220529513). The 10th digit is a mathematical control digit computed via the official Modulo 10/9 checksum algorithm.

Sole proprietorships and unincorporated freelancers in Turkey frequently use their 11-digit Turkish Republic Identity Number (T.C. Kimlik Numarası — TCKN) for tax reporting, whereas incorporated corporate entities use the 10-digit VKN. For commercial cross-border operations and mandatory electronic invoicing, businesses must be verified against the official GİB taxpayer database.

Because Turkey is not an EU member state, Turkish VAT and VKN numbers cannot be validated in the European Commission VIES database. If you submit a TR tax number to VIES, it will return an invalid member state error. Instead, official verification must be conducted directly against the GİB e-Fatura and Taxpayer Registry.

VIESAC connects directly to the GİB infrastructure, combining automated vision captcha resolution, SmartRouter™ failover, and SmartCache™ 24-hour verification. When verifying Turkish suppliers, manufacturers, or logistics partners, VIESAC generates tamper-proof PDF audit certificates containing cryptographic timestamps, technical evidence XML, and statutory 10+ year audit defense documentation.

Frequently asked questions about Turkish VKN and VAT validation

What is a Turkish VKN and what format does it follow?

A VKN (Vergi Kimlik Numarası) is Turkey's official tax identification number for companies and corporate entities. It consists of exactly 10 digits, where the final digit is a checksum validated by the official GİB Modulo 10/9 algorithm. In international business contracts and cross-border invoices, it is prefixed with TR (e.g. TR6220529513). If you enter the 10 digits without the prefix, our tool automatically normalizes it to TR.

Can I verify a Turkish VAT or VKN number in the EU VIES system?

No. Turkey participates in the EU Customs Union but is not an EU member state and not part of the EU VAT directive area. Therefore, Turkish corporate tax numbers do not exist in the European Commission VIES database. Official verification must be performed directly through the Gelir İdaresi Başkanlığı (GİB) e-Fatura taxpayer system. VIESAC provides direct, automated GİB queries and issues official timestamped verification certificates.

What is the difference between Turkish VKN and TCKN?

VKN (Vergi Kimlik Numarası) is a 10-digit tax number issued to corporations, partnerships, and institutions. TCKN (T.C. Kimlik Numarası) is an 11-digit national identification number assigned to Turkish citizens, which sole proprietorships (şahıs şirketi) use for domestic taxation. In B2B cross-border trade, corporate transactions invariably rely on the 10-digit VKN.

What happens if I enter an EU VAT number into this Turkish validator?

Our intelligent pre-validation system instantly recognizes VAT prefixes from all 27 EU member states (such as DE, FR, IT, ES, PL, etc.). If you paste an EU VAT number, the validator displays an alert with a one-click redirect to verify the number in the EU VAT (VIES) Validator.