Chapter 1-21 Tax Identification Numbers ITINs An Individual Taxpayer Identification Number (ITIN) is a number issued by the IRS to a Non-U.S. Citizen who does not have an Social Security Number (SSN), but is required to provide a U.S. Government issued identification number as part of a specific financial transaction or to file a tax return with the IRS. An ITIN is not acceptable as a substitute for an SSN for a customer applying for a learner's permit, driver's license or other RMV documents. 01/12 1:132