Tax file numbers

A tax file number (TFN) is a unique number issued to each taxpayer by the ATO. The TFN is used to identify taxpayers, detect non-disclosure of income and to enable the ATO to match the details of income disclosed in a taxpayer’s return with details it receives from other sources. While this is primarily in the areas of employment and investment income, it is also used in relation to the paid parental leave scheme and other areas not directly related to tax (for example, quotation of a TFN may be a precondition to receiving a Commonwealth income support payment and may be necessary for enrolment at a higher education institution or in an Open Learning course). Quotation of TFNs is also relevant in other tax areas, such as superannuation.

While there is no obligation for a taxpayer to quote a TFN in relation to employment and investments, in many circumstances the payer will be required to withhold tax from any payment at the top marginal rate plus the Medicare Levy where the recipient’s TFN has not been quoted.

There are significant penalties for the abuse of the TFN system.

Instruction on how to apply for a TFN are on the ATO website: here for individuals and here for non-individuals.