what is my social security number in australia
National identification number In Australia, the Tax File Number (TFN) is issued by the Australian Taxation Office (ATO) to individuals and businesses to track them for income tax purposes. Similar to the Social Security Number (SSN) in the US, each individual's TFN is unique, and does not change throughout their lifetime. However, unlike its U.S. counterpart, Australian law specifically prohibits the use of the TFN as a national identification number, and restricts the use of the TFN to tracking individuals for filing income taxes, superannuation contributions and receiving state welfare benefits.