Who Needs an ITIN? Complete Eligibility Guide

Who Qualifies for an ITIN?

The IRS issues ITINs to individuals who meet two criteria: they have a federal tax reporting requirement, and they are not eligible for a Social Security Number. This covers a broad range of people living inside and outside the United States.

You qualify for an ITIN if you fall into any of the following categories defined by the IRS on Form W-7:

• Non-resident aliens required to file a US tax return
• Resident aliens (based on the substantial presence test) who file a US tax return but cannot get an SSN
• Dependents or spouses of a US citizen or resident alien who are claimed on a tax return
• Dependents or spouses of a non-resident alien visa holder who are claimed on a tax return
• Non-resident aliens claiming a tax treaty benefit
• Non-resident alien students, professors, or researchers who file a US tax return or claim an exemption

Each of these categories has specific documentation requirements and reasons for applying. The sections below break down the most common groups of people who need an ITIN, with links to dedicated guides for each audience.

ITIN for Freelancers

Foreign freelancers and independent contractors who perform services for US clients often receive 1099-NEC or 1099-MISC forms reporting their income. US companies are required to collect a taxpayer identification number from anyone they pay more than $600 in a tax year. If you do not have an SSN, you need an ITIN to provide on Form W-8BEN or W-9 (depending on your tax residency status).

Without a valid ITIN, US clients must withhold 30% of your payments for federal taxes. By obtaining an ITIN and submitting the proper withholding forms, you may reduce this rate significantly or eliminate it entirely if a tax treaty applies between your country and the US.

See our detailed walkthrough for ITIN for freelancers to learn how to set up your tax profile correctly and avoid unnecessary withholding.

ITIN for International Students

International students on F-1, J-1, or M-1 visas who earn taxable income in the US generally need a taxpayer identification number. Students employed on campus or through CPT/OPT often receive an SSN through their employer. However, students who earn only scholarship or fellowship income, or who need to claim a tax treaty exemption without employment, may not qualify for an SSN and will need an ITIN instead.

Many countries have tax treaty provisions that exempt scholarship and fellowship income from US taxation. To claim this exemption, you need an ITIN and must file Form 8233 or attach Form W-8BEN to your tax return. Without an ITIN, your university or institution must withhold taxes at the standard non-resident rate on any taxable scholarship amounts.

Learn more about eligibility and the application process in our guide for ITIN for international students.

ITIN for F-1 Visa Holders

F-1 visa holders are international students pursuing academic studies in the US. While many F-1 students obtain an SSN through on-campus employment or authorized off-campus work, some F-1 students need an ITIN instead. This is especially true for students who receive taxable scholarships or fellowships but do not have employment authorization, students who need to claim tax treaty benefits, or students whose spouses (on F-2 visas) need a taxpayer identification number.

F-1 students are generally considered non-resident aliens for tax purposes during their first five calendar years in the US (the “exempt individual” rule under the substantial presence test). This means they file Form 1040-NR and may benefit from tax treaty provisions that their home country has with the US. An ITIN is necessary to access these benefits if no SSN is available.

Our detailed guide covers everything F-1 students need to know: ITIN for F-1 visa holders.

ITIN for LLC Owners

Foreign nationals who form a US LLC need a taxpayer identification number for multiple purposes. While the LLC itself gets an EIN (Employer Identification Number), the individual owner needs either an SSN or ITIN. The IRS requires a “responsible party” TIN on the EIN application (Form SS-4), so you typically need your ITIN before you can obtain your LLC's EIN.

Beyond the EIN application, LLC owners need an ITIN to file their personal US tax returns. Single-member LLCs owned by foreign nationals are treated as disregarded entities for tax purposes, meaning the income flows through to your personal return. Multi-member LLCs file a partnership return (Form 1065), and each foreign member needs an ITIN to report their share of the income on their individual return.

Our guide on ITIN for LLC owners walks through the entire process from ITIN application to EIN to business banking.

ITIN for Immigrants

Immigrants who are in the process of adjusting their status, waiting for work authorization, or otherwise not yet eligible for a Social Security Number still have US tax obligations if they earn income. The IRS requires all individuals with a filing requirement to report their income, regardless of immigration status. An ITIN provides the taxpayer identification number needed to comply.

Filing taxes with an ITIN can also support your immigration case. Consistent tax filing demonstrates good moral character and compliance with US law, which immigration judges and USCIS officers may consider favorably during adjustment of status proceedings, visa renewals, or naturalization applications. Your ITIN application and tax filings are confidential, and the IRS does not share this information with immigration enforcement agencies.

Learn how to get started with our ITIN for immigrants guide.

How to Check if You Need an ITIN

Use this quick checklist to determine whether you need an ITIN:

1. Do you already have a Social Security Number? If yes, you do not need an ITIN. Use your SSN for all tax filings.
2. Are you eligible for a Social Security Number? If you are a US citizen, green card holder, or have valid work authorization, apply for an SSN at the Social Security Administration. You do not need an ITIN.
3. Do you have a US tax filing obligation? This includes earning US-source income, being claimed as a dependent or spouse on a US tax return, needing to claim a tax treaty benefit, or having backup withholding applied to your payments. If yes, proceed to step 4.
4. You need an ITIN. If you have a US tax obligation but no SSN eligibility, the ITIN is the correct taxpayer identification number for you. Gather your documents and submit Form W-7 to the IRS, or work with a Certifying Acceptance Agent to streamline the process.

If you are still unsure, a tax professional or Certifying Acceptance Agent can review your specific situation and confirm whether an ITIN is required. At itin.so, our team evaluates your eligibility as part of the application process.