What is an Itin?
Understanding ITIN Program Requirements: A Guide for Applicants
If you're navigating the U.S. tax system but are ineligible for a Social Security Number (SSN), you may need an Individual Taxpayer Identification Number (ITIN). This nine-digit number, issued by the Internal Revenue Service (IRS), allows individuals to meet their federal tax obligations. Whether you're a nonresident alien, a resident alien, or a dependent/spouse of a U.S. taxpayer, understanding ITIN program requirements is essential. Here’s everything you need to know about applying for or renewing an ITIN.
What is an ITIN?
An ITIN is a tax processing number designed for individuals who are not eligible for an SSN but have a federal tax filing requirement. It’s commonly used by:
Nonresident aliens required to file U.S. tax returns.
Resident aliens (based on days present in the U.S.) filing tax returns.
Dependents or spouses of U.S. citizens or resident aliens.
Foreign investors or individuals with U.S. income who must report it for tax purposes.
Who Needs an ITIN?
You need an ITIN if you:
Are legally required to file a federal income tax return.
Want to claim a refund or allowable tax benefits.
Must provide a taxpayer identification number for another federal tax purpose.
ITINs are also used by foreign investors in real estate and by individuals applying for mortgages when they lack an SSN.
How to Apply for an ITIN
To apply for an ITIN, follow these steps:
Complete Form W-7
Fill out Form W-7, "Application for IRS Individual Taxpayer Identification Number." Each applicant (including dependents) must submit their own form 15.Attach a Federal Tax Return
Most applicants must include a completed U.S. federal income tax return (e.g., Form 1040 or 1040-NR) with their application unless they qualify for an exception12. Exceptions may apply in cases such as third-party withholding on passive income or claiming treaty benefits.Provide Supporting Documents
Submit original documents or certified copies proving your identity and foreign status. Examples include passports, visas, and birth certificates. At least one document must include your photograph if you’re over 18 and not a student.Submit Your Application
Mail your completed application package to the IRS Tax Processing Center in Austin, Texas, or visit an IRS-authorized Acceptance Agent or Taxpayer Assistance Center (TAC).