SECTION 2. BACKGROUND

Section 6109(a)(1) generally provides that a person must furnish a taxpayer identifying number (TIN) on any return, statement, or other document required to be made under the Internal Revenue Code (Code). For taxpayers eligible to obtain a social security number (SSN), the SSN is the taxpayer's TIN. See section 6109(d); section 301.6109–1(d)(4). Taxpayers who are required under the Code to furnish a TIN, but who are not eligible for a SSN, must obtain an ITIN from the Service. See Section 301.6109–1(d)(3)(ii). A taxpayer must apply for an ITIN on Form W–7, Ap- plication for the IRS Individual Taxpayer Identification Number.

ITINs were not intended to be used as proof of identity for nontax purposes ( e.g., to obtain a driver's license, to claim legal residency, to seek employment in the United States, or to apply for welfare and health benefits) and may not be reliable proof of an individual's identity for those purposes. To help eliminate the nontax use of ITINs, the Service now is requiring taxpayers to attach the original, completed tax return for which the ITIN is needed, such as a Form 1040, to the Form W–7.