What the Tax number (VKN or TCKN) is
The Tax number (VKN or TCKN) is the number Revenue Administration (GİB) assigns to a taxpayer in Türkiye. It follows you across every tax you deal with: KDV, income tax and withholding. Businesses that pay you will ask for it before they release payment, because they report their suppliers to Revenue Administration (GİB) by this number.
Who needs one
Every Turkish citizen already has a tax number: it is their 11-digit T.C. Kimlik Numarası. A foreign national with a Yabancı Kimlik Numarası uses that. Everyone else — companies, partnerships, foreign individuals with no Turkish ID — is issued a 10-digit Vergi Kimlik Numarası (VKN). Having a number is not the same as being registered: traders, self-employed professionals and corporate taxpayers must separately notify the tax office that they have started business (VUK 153).
How to register, step by step
- If you are a foreign individual or company with no Turkish number yet, apply for a potential tax number from the 'Potential Tax Identification Number Application' link on the dijital.gib.gov.tr home page — it needs no login.
- Sole traders: file the işe başlama bildirimi with the tax office within 10 days of starting, yourself or through a licensed accountant or lawyer (VUK 168).
- Companies: you do not file it. The trade registry office notifies the tax office within 10 days of incorporation, from the registration papers.
- Expect a yoklama — a tax inspector visits the business address to confirm the activity is real before the file is opened.
- Log in to Dijital Vergi Dairesi with the credentials the tax office issues; your number, tax office and vergi levhası are all there.
How to find or check a Tax number (VKN or TCKN)
GİB publishes no open register that turns a number into a name. What it does publish, at ebelge.gib.gov.tr, is the current list of everyone enrolled in e-Fatura, e-Arşiv, e-İrsaliye and e-SMM — you check a counterparty's VKN or TCKN against it before deciding whether you must invoice them as e-Fatura. Your own number, tax office and vergi levhası are in Dijital Vergi Dairesi once you log in.