National Insurance number
The National Insurance number is used as a reference number in the Pay As You Earn system, and also by the self-employed. It is also used in applications for Individual Savings Accounts (ISAs), to check that an individual has opened only one ISA in a tax year.
Pensions in Turkey
Until May 2006, there were three separate social security institutions: SSK, for private and public sector workers; Emekli Sandiği (ES), for civil servants; and Bağ-Kur, for self-employed workers and farmers. In 2006 these were all merged into one institution, the Sosyal Güvenlik Kurumu (Social Security Institution, SGK).