How to Get an ITIN: A Complete Guide
If you don’t qualify for a Social Security Number but still need to file taxes or do business in the United States, an Individual Taxpayer Identification Number — ITIN — is the document that makes it possible. Whether you’re a nonresident alien, a foreign national earning U.S. income, or a dependent on someone else’s return, understanding how the ITIN process works can save you from costly delays and mistakes.
Here’s a clear breakdown of who qualifies, what you need, how to apply, and how long it takes.
Who Is Eligible for an ITIN?
The IRS issues ITINs exclusively to individuals who are not eligible to obtain a Social Security Number but have a federal tax filing requirement — or need to be included on a U.S. tax return filed by someone else.
Common eligible categories include:
Nonresident aliens who earn income from U.S. sources and are required to file a federal return. This includes freelancers, content creators, investors, and business owners operating from abroad with U.S. clients or revenue streams.
Foreign nationals residing in the U.S. who don’t meet the eligibility criteria for an SSN — such as individuals on certain visa types — but are subject to U.S. tax obligations.
Dependents and spouses of U.S. citizens or resident aliens, when those individuals are themselves ineligible for an SSN. This is a common situation for expats whose family members live abroad.
Resident aliens (based on the IRS substantial presence test) who file a U.S. return but cannot obtain an SSN.
One thing to be clear about: an ITIN is a tax processing number only. It does not authorize work in the U.S., grant immigration status, or make you eligible for Social Security benefits or the Earned Income Tax Credit.
What Documents Do You Need?
The ITIN application requires you to prove two things: your foreign status and your identity. The IRS accepts a specific list of documents for this purpose — and they must be original documents or certified copies issued by the originating agency. Notarized photocopies are not accepted.
The IRS recognizes 13 types of documents. The passport is the only document that satisfies both requirements on its own, which is why it’s the most commonly used.
Other accepted documents include:
- U.S. Citizenship and Immigration Services (USCIS) photo ID
- U.S. or foreign driver’s license
- National ID card (must show photo, name, address, date of birth, and expiration date)
- U.S. state ID card
- Foreign voter registration card
- Civil birth certificate (for dependents under 18)
- Medical records (for children under 6)
- U.S. military or foreign military ID
- School records (for dependents under 14 or students)
- Visa
If you’re using documents other than a passport, you’ll likely need to submit at least two, ensuring one establishes foreign status and another confirms identity.
Keep in mind that the IRS will hold your original documents for the duration of the processing period — which is a significant concern for applicants using their passport. One way to avoid this is to work through a Certified Acceptance Agent (CAA), who is authorized by the IRS to review your original documents and send certified copies on your behalf, so you never have to mail your passport.
The Application Process
There are three ways to submit your ITIN application:
Option 1 — Mail your application directly to the IRS. You’ll complete Form W-7 (the official ITIN application) and attach it to your federal tax return (if applicable), along with all required identity and foreign status documents. Everything gets mailed to the IRS’s Austin, Texas facility.
Option 2 — Apply in person at an IRS Taxpayer Assistance Center (TAC). Some TAC locations are authorized to review and certify your documents, which means you get your originals back the same day. Appointments are required and availability varies by location.
Option 3 — Work with a Certifying Acceptance Agent (CAA). CAAs are individuals and businesses authorized by the IRS to assist applicants with ITIN applications. They can verify your documents, complete the Form W-7 on your behalf, and submit everything without you having to mail original documents. This is the most common route for international clients, creators, and business owners who want to avoid the risk of lost documents and processing confusion.
Regardless of the route you choose, the core application document is IRS Form W-7. The form will ask for your full name, mailing address, reason for applying, and supporting document details. You’ll also indicate your applicant category — for example, “nonresident alien required to get an ITIN to claim tax treaty benefits” or “dependent of a U.S. citizen.”
If you’re applying along with a tax return, the return must be attached to the W-7. Exception: if you’re applying based on a treaty claim or certain other exceptions, you may not need to file a return.
Processing Times
The IRS generally processes ITIN applications within 7 to 11 weeks from the date they receive a complete and accurate application. During peak filing season — January through April — processing can run toward the longer end of that window. For applications submitted outside the U.S., the IRS advises allowing up to 9 to 11 weeks.
Once approved, the IRS will send your ITIN by mail to the address on your W-7. If you applied with a tax return, the return is processed at the same time.
A few things that commonly slow down the process:
- Submitting incomplete documents or missing signatures on the W-7
- Sending photocopies instead of originals or certified copies
- Failing to attach the required tax return (when applicable)
- Name inconsistencies between your ID and the W-7 form
If 11 weeks pass without a response, the IRS does allow you to check on the status of your application by calling their toll-free line or visiting a TAC.
One additional note: if your ITIN goes unused for three consecutive tax years, the IRS will deactivate it. If that happens, you’ll need to renew it before it can be used again on a return.
Don’t Navigate This Alone
The ITIN process looks straightforward on paper, but the reality — especially for international applicants, creators earning U.S. income, and expats navigating multiple tax systems — is that small errors cause real delays, and those delays can hold up your ability to file, claim treaty benefits, or process payments.
If you want to get it done right the first time, we can handle the full process as a Certifying Acceptance Agent — from document review to IRS submission — so you stay protected and compliant without the guesswork.
Book a free consultation here and let’s get your ITIN sorted.