Every year, millions of people work, earn income and do business in the United States without a Social Security number. And every year the same question comes up: how do I file my taxes if I don't have a Social?
The answer is the ITIN. It's one of the most important —and most misunderstood— tools in the U.S. tax system. Myths swirl around it in both directions: some believe an ITIN grants permissions it doesn't, and others avoid getting one out of fear of something the ITIN isn't.
In this guide we explain exactly what an ITIN is, who needs it, how to apply, how long it takes and how to keep it valid.
What is an ITIN?
ITIN stands for Individual Taxpayer Identification Number. It's a nine-digit number issued by the IRS for people who are required to have a tax identification in the United States but are not eligible for a Social Security number (SSN).
It looks just like a Social —the same nine-digit format— but it always starts with the number 9. That's the fastest way to tell them apart.
Its purpose is a single, very specific one: to let a person meet their federal tax obligations. The IRS created it because U.S. tax law doesn't ask about your immigration status: if you earn income in the country, you must report it. The ITIN is the mechanism that makes that possible.
Who needs an ITIN?
You need an ITIN if you're required to file, or appear on, a federal tax return and don't qualify for an SSN. The most common cases we see:
- Business owners without a Social. A remodeling contractor in San José, a transport owner-operator in Nashville or a home baker in Hialeah: if they earn income, they have an obligation to file.
- Foreign members of a U.S. LLC. An investor from Mexico or Colombia with a stake in a Florida LLC needs an ITIN for their corresponding return.
- Spouses and dependents who are included on someone else's return for an allowed tax benefit.
- Non-residents with U.S.-source income: rent from a property in Orlando, royalties, gains from selling real estate.
- Foreigners claiming tax-treaty benefits between their country and the United States.
- Students, researchers and professors on a visa who don't qualify for an SSN.
What an ITIN is NOT
This is the most important section of the article, because this is where the problems start.
An ITIN does not:
- Authorize you to work legally in the United States.
- Grant, change or affect your immigration status.
- Entitle you to Social Security benefits.
- Serve as official ID outside the tax context.
An ITIN is, literally, a number to file taxes. Nothing more and nothing less.
So what is an ITIN for?
Its function is tax-related, but the practical effects are real and valuable:
- Complying with the law. Filing taxes is a legal obligation. Meeting it keeps you in good standing with the IRS and avoids penalties and accrued interest.
- Getting refunds. If too much tax was withheld, without an ITIN there's no way to get it back.
- Building a tax history. Years of filed returns are documentary support that counts in your favor in many processes. A clean history can't be improvised later.
- Opening financial doors. Many banks accept the ITIN to open accounts, and several institutions use it to evaluate mortgage or business-credit applications.
- Running your business properly. If you have an LLC, your bookkeeping, your personal return and the company's return all need a valid ID number behind them.
Each of these points deserves a longer look; we dig into them in Benefits of having an ITIN if you don't have a Social Security number.
A warning about tax credits
Filing your return is an obligation, but how much you get back as a refund depends on tax credits whose requirements change with legislation.
Some credits —like the Earned Income Tax Credit (EITC)— have never been available to those who file with an ITIN. Others, like the Child Tax Credit or education credits, have had their identification requirements changed at different times, especially affecting mixed-status families.
How to apply for an ITIN
Step 1: Complete Form W-7
Form W-7 (Application for IRS Individual Taxpayer Identification Number) is the official application. You must mark the reason you're requesting the number, and that reason determines what additional documentation is required.
Step 2: Attach the tax return
In most cases, the W-7 is filed together with your paper federal return. It can't be filed electronically, because the IRS needs to assign the number before processing the return. There are documented exceptions —tax treaties, certain passive income, opening accounts with withholding— that allow you to apply without an attached return.
Step 3: Prove identity and foreign status
The IRS accepts a specific and limited list of documents, and each one must be current. The passport is the only one that works on its own; any other document must be combined with a second one (birth certificate, consular ID, foreign license, among others).
And here's the critical point: the IRS requires original documents or copies certified by the issuing agency. That means mailing your physical passport to Texas and waiting weeks until you get it back.
Step 4: Submit the application
There are three routes:
- By mail to the IRS processing center, with your original documents inside the envelope.
- In person at an IRS Taxpayer Assistance Center, by appointment.
- Through a Certifying Acceptance Agent (CAA), who verifies your documents and returns them to you on the spot.
Why use a Certifying Acceptance Agent (CAA)?
A Certifying Acceptance Agent is a person or company formally authorized by the IRS to verify the authenticity of an ITIN applicant's identity documents.
The practical difference is huge:
| On your own | With a CAA | |
|---|---|---|
| Your passport | Mailed to the IRS | Stays with you |
| W-7 pre-review | None | Verified before sending |
| Formatting errors | Found weeks later, by letter | Fixed before filing |
| Follow-up | You alone | The agent follows the case |
Most rejected applications don't fail because of the form, but because of the documents: a name that doesn't match the passport exactly, an expired document, a copy that isn't certified by the issuing authority. Each of those errors means a letter from the IRS and weeks lost —sometimes right in the middle of tax season.
ITIN expiration and renewal
An ITIN doesn't last forever.
- Main rule: if your ITIN doesn't appear on at least one federal return for three consecutive tax years, it expires on December 31 of the third year.
- Additional rule: any ITIN issued before 2013 that was never renewed is already expired, regardless of recent use.
If you file a return with an expired ITIN, the IRS will process it but will deny certain credits and send you a notice. Recovering them later requires renewing and filing an amended return (Form 1040-X), with the delay that implies for your refund.
To renew, you use the same Form W-7, marking that it's a renewal. Renewal doesn't require attaching a return, has no IRS cost and can be done any time of year —ideally before the season starts. Also, if several family members have ITINs about to expire, they can be renewed together.
Your number doesn't change. When you renew, you get the same ITIN as always.
How long does the process take?
The IRS estimates about seven weeks to get a response under normal conditions, and nine to eleven weeks during peak season (mid-January to late April) or when the application is sent from abroad. In high-volume periods it can take longer, so it's best to confirm current timelines before planning.
The practical recommendation is simple: don't leave the ITIN for March. Neither the initial application nor the renewal.
ITIN and your business: how they connect
It's common to confuse three different numbers:
| SSN | ITIN | EIN | |
|---|---|---|---|
| Who issues it | Social Security | IRS | IRS |
| Who it identifies | Person | Person | Company |
| Authorizes work | Yes | No | Not applicable |
| Typical use | Employment, benefits | Personal return | LLC, corporation, payroll |
If you have an LLC, the company is identified by its EIN, but you, as a member, need your own tax ID —SSN or ITIN— for the personal return where the profits that pass from the company to you are reported. Both numbers coexist; they don't replace each other. (Haven't formed your company yet? Check out our company formation service.)
Frequently asked questions
Can I apply for an ITIN if I have no immigration status?
Yes. The ITIN exists precisely because the obligation to file taxes doesn't depend on immigration status. Form W-7 doesn't ask about it.
How much does an ITIN cost?
The IRS doesn't charge to issue or renew it. What you pay for is the professional preparation and certification service, if you choose to use it.
Can I work with an ITIN?
No. The ITIN doesn't grant employment authorization.
I now have a Social. What do I do with my old ITIN?
You must notify the IRS so it consolidates your tax history under the SSN. From that point on, you stop using the ITIN.
Can I open an LLC with an ITIN?
Yes. No state requires a Social to be a member of an LLC. The company will get its EIN separately.
Can I claim my children as dependents with an ITIN?
You can include them on your return, but the identification requirements for each credit vary according to current law. It's best to review your specific case before filing.
Does my ITIN work to get a driver's license?
It depends on the state and its own rules. The ITIN by itself is not an official ID document.
Conclusion
The ITIN is neither a shortcut nor a privilege: it's the path U.S. law established so that anyone with a tax obligation can meet it. Getting it right, on time and with the correct documents saves you months of delays and builds a history that's worth more than it seems.
At DISSAU, as an IRS-Authorized Certifying Acceptance Agent, we guide you through the application, the renewal and the full return —in Spanish, with clear answers. Need your ITIN or to renew the one you have? Check out our ITIN application service or book a call.
This article is for informational purposes and does not constitute personalized tax advice. IRS rules and tax law change over time; confirm current information at irs.gov or ask us directly about your case.
