An Individual Taxpayer Identification Number (ITIN) is a tax processing number issued by the Internal Revenue Service (IRS). People who need a U.S. taxpayer identification number but are unable to receive a Social Security Number (SSN) from the Social Security Administration must acquire an ITIN number for tax purposes.

An ITIN number is composed of 9 digits beginning with “9” and is formatted like an SSN (NNN-NN-NNNN). U.S. residents or non-citizens must have an ITIN number in accordance with the Revenue Code to file their tax returns.