# When did KVKK, e-invoicing, İYS start? Timeline | Corex360 > When did KVKK, e-invoicing, e-archive, e-ledger, İYS, VERBİS, KEP, and e-notification start? Gazette and effective dates in one table, with official links. Source: https://www.corex360.com/en/blog/turkish-business-regulation-timeline Last updated: 2026-09-29 --- ![Unlabelled pastel archive boxes lined up left to right on a shelf by a window, one pulled out] Regulation # Business regulation timeline: when KVKK, e-invoicing, İYS, and KEP began in Turkey The business regulation timeline is a single table of the Official Gazette and entry-into-force dates of Turkish rules that affect business software: the Labour Law, KVKK, VERBİS, e-invoicing, e-archive, e-ledger, İYS, KEP, and e-notification. Every row links to the official text. [Request a demo](https://www.corex360.com/en/contact?konu=bi#form) [Corex360](https://www.corex360.com/en) [Blog](https://www.corex360.com/en/blog) Business regulation timeline: when KVKK, e-invoicing, İYS, and KEP began in Turkey Contents - 01 Which rule came into force when? - 02 When did KVKK come into force? - 03 When did VERBİS registration start? - 04 When did e-invoicing and e-archive start? - 05 When did İYS become mandatory? - 06 When did KEP and e-notification become mandatory? - 07 What does Corex360 not take on under these rules? Ş **[Şevket Erer](https://www.corex360.com/en/blog#blog-hakkinda)** Co-founder, AI Specialist · Corex360 28 September 2026 4 min read [Modules](https://www.corex360.com/en/modules) [Solutions](https://www.corex360.com/en/solutions) The business regulation timeline is a reference table that brings together the dates on which Turkish rules affecting a company's software and record-keeping were published in the Official Gazette and came into force. Read on one line, the [Labour Law](https://www.corex360.com/en/turkish-labour-law-table), KVKK (Turkey's data protection law), VERBİS, e-invoicing, e-archive, e-ledgers, İYS, KEP, and e-notification show when each duty began and which one changed later. Every row in the table rests on the official text. ** 01. ## Which rule came into force when? ** Short answer The timeline lists the rules in order of Official Gazette date; the entry-into-force column gives the date together with the article it rests on. The publication date and the entry-into-force date are often not the same. Some articles of KVKK came into force six months after publication, and the Turkish Commercial Code more than a year after. When choosing software or drafting a contract, the date that matters is the entry-into-force date; the article reference in the table shows where it comes from. Turkish business regulation timeline | Rule | Official Gazette | In force | Who it concerns | |---|---|---|---| | Labour Law No. 4857 | 10.06.2003 | On publication (Art. 121) | Workplaces, employers, and workers | | Electronic Signature Law No. 5070 | 23.01.2004 | Six months after publication (Art. 25) | Anyone using electronic signatures | | Social Insurance and General Health Insurance Law No. 5510 | 16.06.2006 | In stages; remaining provisions at the start of October 2008 (Art. 108) | Insured people and employers | | Turkish Commercial Code No. 6102 | 14.02.2011 | 01.07.2012 (Art. 1534) | Merchants and commercial enterprises | | Registered Electronic Mail (KEP) Regulation | 25.08.2011 | 01.07.2012 (Art. 29) | KEP providers and users | | Electronic Ledger General Communiqué (No. 1) | 13.12.2011 | On publication; authorised taxpayers from 01.01.2012 | Taxpayers keeping electronic ledgers | | Tax Procedure Law General Communiqué No. 421 | 14.12.2012 | On publication | Those required to use e-invoicing and e-ledgers | | Tax Procedure Law General Communiqué No. 433 (e-archive) | 30.12.2013 | On publication | Issuers of e-archive invoices | | Law No. 6563 on the Regulation of Electronic Commerce | 05.11.2014 | 01.05.2015 (Art. 15) | Senders of commercial electronic messages | | Regulation on Commercial Communication and Commercial Electronic Messages | 15.07.2015 | On publication (Art. 18) | Senders of commercial electronic messages | | Personal Data Protection Law No. 6698 (KVKK) | 07.04.2016 | On publication; Arts. 8, 9, 11, and 13 to 18 six months later (Art. 32) | Individuals and legal entities processing personal data | | General Communiqué on the Withholding and Premium Service Return (No. 1) | 18.02.2017 | Pilot provinces in stages; nationwide 01.07.2020 (Art. 15) | Employers | | Regulation on the Data Controllers' Registry | 30.12.2017 | 01.01.2018 (Art. 19) | Data controllers | | Law No. 7101, Art. 48 (Notification Law Art. 7/a) | 15.03.2018 | 01.01.2019 (Art. 66/a) | Recipients of electronic notification, including private-law legal entities | | Data Protection Board decision 2018/88 (VERBİS) | 18.08.2018 | Registration opened 01.10.2018; deadline set by decision 2021/238 at 31.12.2021 | Data controllers required to register | | Electronic Notification Regulation | 06.12.2018 | 01.01.2019 (Art. 32) | Electronic notification through PTT | | Tax Procedure Law General Communiqué No. 509 | 19.10.2019 | On publication; communiqués 397, 421, and 433 repealed | e-invoice, e-archive, e-waybill, and other e-documents | | Amendment to the Commercial Communication Regulation (İYS) | 04.01.2020 | Partly on publication, the rest 01.09.2020 (Art. 19); consent transfer 01.12.2020, recipient check 16.01.2021 (provisional Art. 2) | Senders of commercial electronic messages | | Law No. 7499 (amending KVKK Arts. 6 and 9) | 12.03.2024 | 01.06.2024 (Art. 40/1-a); the old Art. 9(1) applied alongside until 01.09.2024 | Those processing special categories of data or transferring data abroad | ** 02. ## When did KVKK come into force? ** Short answer KVKK, Law No. 6698, was published in the Official Gazette and came into force on 7 April 2016; Articles 8, 9, 11, and 13 to 18 came into force six months after publication. Article 32 of the Law splits entry into force in two: the articles on transfers, data subjects' rights, complaints, and the Authority came into force six months after publication, and the rest on the date of publication. In 2024, Law No. 7499 amended Article 6, on processing special categories of data, and Article 9, on transfers abroad; these amendments came into force on 1 June 2024, and the old Article 9(1) applied alongside the new provision until 1 September 2024. ** 03. ## When did VERBİS registration start? ** Short answer The Regulation on the Data Controllers' Registry came into force on 1 January 2018; under the Board's decision 2018/88, the registration duty started on 1 October 2018. The registration periods were later extended; the Board's decision 2021/238 set the deadline for all groups at 31 December 2021. Who is exempt from registration depends on criteria that change through Board decisions; check the current exemption criteria through the [VERBİS glossary entry](https://www.corex360.com/en/glossary/verbis-data-controllers-registry) and kvkk.gov.tr. ** 04. ## When did e-invoicing and e-archive start? ** Short answer e-invoicing was set out by Communiqué No. 397 on 5 March 2010, the obligation by Communiqué No. 421 on 14 December 2012, and e-archive by Communiqué No. 433 on 30 December 2013; today they are all gathered in Communiqué No. 509. Electronic document rules did not arrive through one law but through general communiqués under the Tax Procedure Law. Communiqué No. 509 came into force on publication on 19 October 2019 and repealed Communiqués 397, 421, and 433; the rules on e-invoices, e-archive invoices, and e-waybills are read from it today. Which taxpayer must move to e-documents from which date depends on turnover and sector; ask your accountant about your own case. ** 05. ## When did İYS become mandatory? ** Short answer The regulation amendment that introduced İYS was published on 4 January 2020; the date for transferring consents to İYS became 1 December 2020, and the recipient check date 16 January 2021. The framework for commercial electronic messages was set by Law No. 6563 on 1 May 2015. The Message Management System (İYS) came with the 2020 regulation amendment; the transfer and check dates were earlier in the first text and moved to today's dates by the amendment of 28 August 2020. The [table in the İYS glossary entry](https://www.corex360.com/en/glossary/iys-commercial-message-consent) shows which messages need consent. ** 06. ## When did KEP and e-notification become mandatory? ** Short answer The KEP Regulation and the Turkish Commercial Code came into force on 1 July 2012; the electronic notification obligation for private-law legal entities began on 1 January 2019. Article 18(3) of the Turkish Commercial Code puts registered electronic mail on the same footing as a notary and registered letter for notices of default, termination, and rescission between merchants. Law No. 7101, which amended Article 7/a of the Notification Law, made private-law legal entities recipients of electronic notification, and this came into force on 1 January 2019. The [KEP glossary entry](https://www.corex360.com/en/glossary/kep-registered-email-turkey) explains what KEP is and how much weight it carries as evidence. ** 07. ## What does Corex360 not take on under these rules? ** Short answer Corex360's accounting integration options list shows e-Invoice and e-Archive (GİB, the portal of Turkey's Revenue Administration); tracking tax obligations, VERBİS registration, and İYS consent remain the business's own duties. This timeline shows when each duty began, not which duty a piece of software fulfils on its own. What is known on the Corex360 side is that its accounting integration options list shows DİA, e-Invoice and e-Archive (GİB, the portal of Turkey's Revenue Administration), Logo, Mikro, Netsis, and Paraşüt. Tracking the date an e-document obligation starts, registering with the registry, and obtaining consent for commercial messages are the work of the business and its advisers. This article is not legal advice; the dates were read from the official texts, so check the texts in the Sources list for later changes. ## Sources - [Law No. 6698 on the Protection of Personal Data (mevzuat.gov.tr, art. 32)](https://www.mevzuat.gov.tr/mevzuatmetin/1.5.6698.pdf) Last checked 28 September 2026 - [Law No. 7499, Official Gazette 12.03.2024](https://www.resmigazete.gov.tr/eskiler/2024/03/20240312-1.htm) Last checked 28 September 2026 - [Personal Data Protection Board decision 2018/88 (VERBİS registration start)](https://www.kvkk.gov.tr/Icerik/5272/2018-88) Last checked 28 September 2026 - [Personal Data Protection Board decision 2021/238 (VERBİS deadline extension)](https://www.kvkk.gov.tr/Icerik/6905/2021-238) Last checked 28 September 2026 - [Tax Procedure Law General Communiqué No. 509 (mevzuat.gov.tr)](https://www.mevzuat.gov.tr/MevzuatMetin/yonetmelik/9.5.33905.pdf) Last checked 28 September 2026 - [Regulation on Commercial Communication and Commercial Electronic Messages (mevzuat.gov.tr)](https://www.mevzuat.gov.tr/mevzuat?MevzuatNo=20914&MevzuatTur=7&MevzuatTertip=5) Last checked 28 September 2026 - [Regulation on the Registered Electronic Mail System, Official Gazette 25.08.2011](https://www.resmigazete.gov.tr/eskiler/2011/08/20110825-7.htm) Last checked 28 September 2026 - [Law No. 7101, Official Gazette 15.03.2018 (e-notification)](https://www.resmigazete.gov.tr/eskiler/2018/03/20180315-28.htm) Last checked 28 September 2026 - [General Communiqué on the Withholding and Premium Service Return (No. 1) (mevzuat.gov.tr)](https://www.mevzuat.gov.tr/File/GeneratePdf?mevzuatNo=23345&mevzuatTur=Teblig&mevzuatTertip=5) Last checked 28 September 2026 ## How was this page prepared? - Written by: [Şevket Erer](https://www.corex360.com/en/blog#blog-hakkinda), Co-founder, AI Specialist - Sources: legislation, official body, and vendor information is taken from the primary sources in the Sources list on this page; each source shows the date it was last checked. - Product information: sentences about Corex360 rest on the company's product fact records; unconfirmed features are not written. - Use of AI: the Corex360 team writes the text; AI tools are used for drafting and translation. [Publishing principles](https://www.corex360.com/en/about#yayin-ilkeleri) - Dates: first published 28 September 2026 . [Corrections policy](https://www.corex360.com/en/about#duzeltmeler) ## Frequently asked ** 01 What is the business regulation timeline? ** It is a reference page that gathers in one table the Official Gazette and entry-into-force dates of Turkish rules affecting business software. Each row is tied to the official text and the article that sets its entry into force. ** 02 What is the difference between the publication date and the entry-into-force date? ** The publication date is the day the rule appears in the Official Gazette; the entry-into-force date is the day the provision starts to apply and is set in the rule's own entry-into-force article. The two can fall on the same day or months apart. ** 03 When did the withholding and premium service return start? ** The General Communiqué on the Withholding and Premium Service Return was published on 18 February 2017; it was first applied in pilot provinces and started nationwide on 1 July 2020 (Art. 15). ** 04 When did e-ledgers start? ** The Electronic Ledger General Communiqué (No. 1) came into force on publication on 13 December 2011; authorised taxpayers could keep their ledgers electronically from 1 January 2012. ** 05 What did the 2024 KVKK amendment change? ** Law No. 7499 amended Article 6, on processing special categories of data, and Article 9, on transfers abroad; the amendments came into force on 1 June 2024. This answer is not legal advice. ** 06 How is the timeline updated if dates change later? ** When a new amendment is published in the Official Gazette, the row is read again from the official text and the article's update date moves forward. 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