What Is an Individual Taxpayer Identification Number (ITIN)? A Complete Guide
An Individual Taxpayer Identification Number, or ITIN, is a tax processing number issued by the Internal Revenue Service (IRS). It allows people who are required to file or report U.S. taxes but are not eligible for a Social Security number to meet federal tax obligations. An ITIN does not authorize someone to work in the United States or change their immigration status. Knowing who needs an ITIN, how to apply, and when it expires can help prevent filing delays.
What Is an Individual Taxpayer Identification Number?
An ITIN is a nine-digit number used by the IRS to process federal tax returns and administer certain tax laws. It always begins with the number 9, and its format resembles a Social Security number: XXX-XX-XXXX. The IRS issues ITINs to people who need a U.S. taxpayer identification number but cannot obtain a Social Security number (SSN).
For example, a nonresident alien with U.S.-source income may need an ITIN to file a federal tax return. A foreign spouse or dependent listed on a U.S. tax return may also need one in some situations. The exact requirement depends on the person’s circumstances and the tax rules that apply.
An ITIN is for federal tax purposes. It is not a general-purpose identification card, and it does not establish legal immigration status or eligibility to work. It also does not qualify someone for Social Security benefits or, by itself, make someone eligible for tax credits.
Who Needs an ITIN?
A person may need an ITIN if they have a U.S. federal tax filing or reporting requirement, are not eligible for an SSN, and meet IRS application rules. Common examples include:
- Nonresident aliens who must file a U.S. tax return or claim a tax treaty benefit.
- U.S. resident aliens for tax purposes who need to file a federal return but cannot obtain an SSN.
- Spouses or dependents included on a federal tax return when an identification number is required and they are not eligible for an SSN.
- Foreign students, professors, or researchers who have a tax filing requirement or are claiming an applicable tax benefit and cannot get an SSN.
- People involved in certain U.S. tax matters, such as a claim for a tax treaty benefit or a tax return filing related to U.S. income.
These examples are not a complete list. IRS rules can differ depending on residency, income, treaty provisions, and the purpose of the application. A person who is eligible for an SSN generally must apply for an SSN instead of an ITIN. The Social Security Administration determines SSN eligibility.
What an ITIN Does—and Does Not—Do
An ITIN lets the IRS identify a taxpayer on federal tax documents. It can be used when filing a tax return, reporting certain income, or completing other tax processes for which the IRS requires a taxpayer identification number. It helps a person comply with applicable tax rules; it does not confer a broader legal status.
| An ITIN can | An ITIN cannot |
|---|---|
| Identify a taxpayer on federal tax forms | Authorize employment in the United States |
| Allow an eligible applicant to file a required federal tax return | Change or determine immigration status |
| Be used for certain tax reporting or treaty claims | Replace an SSN when someone is eligible for one |
| Help the IRS process a return or tax-related application | Automatically qualify someone for Social Security benefits or tax credits |
Tax credit eligibility depends on the specific credit’s rules, not simply on whether a person has an ITIN. For example, federal rules for credits such as the Earned Income Tax Credit and the Child Tax Credit include identification and eligibility requirements that may not be met by an ITIN alone. Taxpayers should check the current IRS instructions for the credit they are considering.
How to Apply for an ITIN
Most applicants apply using IRS Form W-7, Application for IRS Individual Taxpayer Identification Number. The form asks for identifying details, the reason for applying, and information about the applicant’s tax situation. The IRS requires supporting documents to verify identity and foreign status.
- Confirm that an ITIN is appropriate. An applicant who can obtain an SSN should generally apply for that number instead. Review the Form W-7 instructions to identify the correct application reason.
- Complete Form W-7. Use the current IRS form and instructions. Provide accurate information and select the reason that matches the applicant’s circumstances.
- Prepare identity and foreign-status documents. Submit original documents or copies certified by the issuing agency, unless applying through an IRS-authorized document review option.
- Include a federal tax return when required. In many cases, the applicant attaches Form W-7 to a completed federal income tax return. Certain exceptions allow an application without a return, but the applicant must meet the applicable exception requirements.
- Send the application or submit it through an approved channel. Applicants can mail the package to the IRS, make an appointment at a Taxpayer Assistance Center that offers document review, or work with an IRS-authorized Certifying Acceptance Agent.
Applicants should use the mailing address and submission directions in the current Form W-7 instructions. Requirements and IRS addresses can change. They should also keep copies of the completed form and tax return, but should not mail photocopies of identity documents when the IRS instructions require originals or issuing-agency-certified copies.
Documents Accepted for an ITIN Application
The IRS uses documents to verify both identity and foreign status. A valid passport is the only document that can generally establish both on its own. If the applicant does not submit a passport, the IRS requires a combination of documents that meets its rules.
Depending on the applicant’s situation, acceptable documents may include a national identification card, U.S. or foreign driver’s license, birth certificate, visa, or other records listed in the Form W-7 instructions. Some documents are acceptable only for particular applicants, such as children or students. The document must be current when required and must contain the details specified by the IRS.
Original documents sent by mail are generally returned to the applicant’s address of record. The IRS says it typically returns original identification documents within about 60 days, but applicants should consult current instructions and consider an in-person review option if mailing valuable documents is a concern. A Certifying Acceptance Agent may be able to review documents and submit certified copies rather than sending originals, subject to IRS rules and the agent’s authority.
Applying Through an IRS Office or Acceptance Agent
An applicant who does not want to mail original documents may be able to schedule an appointment at a designated IRS Taxpayer Assistance Center. These centers can review documents and return them during the appointment, but availability and services vary. Applicants should contact the IRS and confirm that the selected location handles ITIN applications before visiting.
Another option is a Certifying Acceptance Agent (CAA). A CAA is authorized by the IRS to assist with ITIN applications and verify certain documents. Some CAAs charge a fee for their services. Using an agent is optional; it does not guarantee faster IRS processing or approval.
Only use an agent listed in the IRS directory or otherwise verify the provider’s authorization. An applicant should understand any service charges, document handling procedures, and the agent’s role before sharing personal information.
How Long Does It Take to Get an ITIN?
Processing time depends on when the application is submitted, whether the package is complete, and the IRS workload. The IRS has commonly advised applicants to allow about seven weeks for processing, with longer estimates possible during peak filing periods or for applications submitted from outside the United States. Current estimates can change, so applicants should check the IRS ITIN information page before filing.
An incomplete Form W-7, a missing tax return when one is required, or insufficient supporting documents can delay processing. The IRS may send a notice requesting additional information or explaining a decision. Applicants should respond by the deadline stated in the notice and use the contact details provided by the IRS.
When Does an ITIN Expire?
An ITIN may expire if it is not used on a federal tax return for three consecutive tax years. Some ITINs also expire under IRS renewal rules for numbers with certain middle digits. The IRS announces which groups need renewal, so a number’s status should be checked rather than assumed.
If an ITIN has expired, a person who still needs it can generally renew it by submitting Form W-7 and the required documents. A renewal application is different from an application for a new ITIN, and the applicant should follow the current IRS instructions. The IRS may allow a renewal application to be submitted with a tax return or in advance, depending on the applicable rules.
An expired ITIN does not necessarily prevent someone from filing a return, but it can delay processing and affect the handling of certain tax benefits or refunds. Renewing before filing may help avoid complications when the person expects to need the number.
ITINs, Tax Returns, and Refunds
Having an ITIN does not mean that a person automatically owes tax, nor does it guarantee a refund. Whether tax is due depends on income, residency classification, deductions, credits, treaty rules, and other facts. A taxpayer may need to file even if no tax is ultimately owed.
When Form W-7 must be submitted with a return, the IRS generally processes the ITIN application and then the return. Applicants should follow the instructions for the relevant tax year and make sure that tax forms are complete. If a return is filed separately without the required identification number, processing may be delayed or the return may not be handled as intended.
Tax rules for nonresident aliens and resident aliens can be substantially different. For example, tax residency under IRS rules is not the same as immigration status. People with cross-border income, treaty questions, or complicated filing obligations may benefit from a qualified tax professional familiar with international tax matters.
Protecting Personal Information
An ITIN application contains sensitive information, including identity documents and personal details. Applicants should use official IRS forms, confirm mailing instructions on IRS.gov, and avoid sending documents to an address found in an unverified message or advertisement. The IRS does not issue an ITIN in exchange for a fee; paid assistance from a tax professional or acceptance agent is a separate service.
Applicants should also be cautious of anyone who promises an ITIN will secure a job, legal immigration status, or guaranteed tax credits. Those claims are not what an ITIN does. The number is a federal tax identifier, and its use is limited to tax-related purposes under applicable rules.
Where to Find Official ITIN Information
The most reliable source for forms, document requirements, renewal details, and processing updates is the IRS. Useful official resources include the IRS Individual Taxpayer Identification Number page, Form W-7 and its instructions, and the IRS directory for finding a Certifying Acceptance Agent. Because procedures and filing rules can change, applicants should consult the current IRS guidance before submitting an application.