Türkiye · GİB Vergi Kimlik Numarası
Turkey VKN Checker
Check that a Turkish Vergi Kimlik Numarası (tax identification number) is 10 digits long and passes the check digit used by the Revenue Administration (GİB).
What is a VKN in Turkey?
A VKN (Vergi Kimlik Numarası) is the 10-digit tax identification number Turkish tax offices assign to companies, other legal entities and foreigners without a foreign identity number — for example 4540536920. Turkish citizens use their 11-digit T.C. Kimlik Numarası instead. The last digit is a check digit.
Turkish VKN format
Ten digits: a 3-digit alpha-group code, a 6-digit sequence number and a check digit.
(from name or title)
number
Format example: 4540536920 (passes the check digit). Digits only — no TR prefix.
- 10 digits: Numeric only — no letters, spaces or separators. The first digit does not indicate company or individual — digits 1–3 are an alpha-group code derived from the name or trade title.
- Check digit: Calculated from the first nine digits and enforced by GİB’s Digital Tax Office. 4540536921 (last digit changed) fails it.
- 11 digits: Usually a T.C. Kimlik Numarası (citizen or sole proprietor) or a foreign identity number — valid tax numbers, but not a VKN.
- 16 digits: A MERSİS trade-registry number, not a tax number. Official GİB documents use digits only, with no country prefix: strip a TR if an ERP adds it.
How to check a Turkish VKN
- 1 Get the 10-digit VKN and tax office (vergi dairesi) from the supplier’s invoice or vergi levhası.
- 2 Enter it above to confirm it is 10 digits and passes the GİB check digit.
- 3 Keep the supplier’s vergi levhası (tax plate) with your records as evidence of its registration.
Frequently Asked Questions
How many digits is a VKN? (VKN kaç haneli?)
A Vergi Kimlik Numarası has 10 digits. Turkish citizens, including sole proprietors, do not have a separate VKN: since 1 July 2006 their 11-digit T.C. Kimlik Numarası (TCKN) is used as their tax number.
What is the difference between VKN and TCKN?
Tax offices issue the 10-digit VKN to companies, other legal entities, ordinary partnerships and foreigners without a foreign identity number. The 11-digit TCKN is the citizen identity number, which also serves as a citizen’s tax number. If you receive 11 digits for a company, ask for its 10-digit VKN.
How do I verify a Turkish tax number officially?
Enter it in the checker on this page to confirm it is 10 digits and passes the official check digit. Official confirmation with the Revenue Administration requires a Turkish login — our Turkey tax ID guide covers the background.
Does a VKN have a check digit?
Yes. The 10th digit is a control digit calculated from the first nine. The formula is not written into legislation, but the Revenue Administration’s Digital Tax Office rejects numbers that fail it — and so does the checker on this page.
Must the buyer’s tax number appear on a Turkish invoice?
The seller’s tax office and number are mandatory. Under Tax Procedure Law (VUK) Article 230 the customer’s tax office and number are required “if any” (varsa), so they must be shown when the buyer has one.
Is a VKN the same as a MERSİS number?
No. The MERSİS number is a 16-digit identifier from the Ministry of Trade’s Central Registry System. If a company gives you 16 digits, ask for its 10-digit VKN. Türkiye is also not in the EU VIES system, so VIES cannot check a VKN.
Last reviewed: , against official sources.
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