In Germany, a social security number (Sozialversicherungsnummer) is a unique identifier assigned to individuals for the purpose of tracking their contributions to the country’s social security system. It is a 12-digit number that is used to track all social security contributions and identify individuals with the German public pension office. The number is divided into five parts and always has the same format: 00 000000 A 000. The first two digits refer to the area number of the local pension office, while the last three digits are a unique identifier for the individual. The social security number is distinctly different from the tax ID (Steueridentifikationsnummer), which is an 11-digit number used by the tax office.

The social security number is an important document that expats in Germany need to have. It is usually issued automatically to individuals when their employer enrolls them in the social security system. The number is required for starting a new job, claiming benefits, drawing a pension, and identifying oneself when accessing the German welfare system. It is also used by employers to take pension contributions from paychecks, so it is important that they receive this number as soon as possible after an individual starts working.

If an individual has just moved to Germany, they do not have a social security number yet. Every year, between January 1 and February 15, the employer gives a Meldebescheinigung zur Sozialversicherung, which contains the social security number. If an individual has lost their social security ID, it is possible to obtain a new one by contacting the statutory health insurance provider, who will request a new ID from the pension insurance provider.