ITIN Number: What It Is and How to Get One
An ITIN number is a 9-digit IRS tax processing number in the format 9XX-XX-XXXX for people who must file U.S. taxes but can't get a Social Security number. It always begins with 9. You get one by filing IRS Form W-7 with a tax return and proof of identity and foreign status - it costs $0. An ITIN number is for tax filing only; it does not authorize work or grant immigration status.
Quick Answer
- What it is
- Individual Taxpayer Identification Number - a 9-digit IRS tax ID
- Format
- 9XX-XX-XXXX - nine digits, always starting with 9
- Who issues it
- The Internal Revenue Service (IRS)
- Who it's for
- People with a U.S. tax purpose who aren't eligible for an SSN
- How to get it
- File IRS Form W-7 with a return and identity/foreign-status proof
- Cost
- $0 - no IRS fee for Form W-7
What an ITIN Number Is
An ITIN number is an Individual Taxpayer Identification Number - a 9-digit number the IRS issues to a person who needs a U.S. taxpayer identifying number for federal tax purposes but is not eligible for a Social Security number. The IRS calls it a tax processing number: its only job is to let the agency match a return, payment, or information report to a specific individual who cannot obtain an SSN. This page focuses on the number itself - its format, who holds one, and how to get it. For the deeper legal explainer, see what is an ITIN.
The word "number" is doing real work here. People often search for the ITIN number because they are looking at a nine-digit value on a document and want to know what it is, whether it is the same as a Social Security number, and what it lets the holder do. The short answer is that an ITIN number looks like an SSN but is not one: it comes from the IRS, it starts with 9, and it is confined to the tax system. It does not appear on a Social Security card, and it is never issued by the Social Security Administration. Understanding those boundaries is usually what the "ITIN number" question is really after.
The ITIN Number Format: 9XX-XX-XXXX
An ITIN number is written exactly like a Social Security number - nine digits in the pattern NNN-NN-NNNN - but it always begins with the digit 9, so it reads as 9XX-XX-XXXX. The IRS confirms on its Taxpayer Identification Numbers page that an ITIN is "a 9-digit number, beginning with the number 9, formatted like an SSN." That leading 9 is the reliable tell that a number is an ITIN and not an SSN. It also differs from an Employer Identification Number, which identifies a business and uses a two-digit prefix, XX-XXXXXXX.
| Number | Format | Identifies | Issued by |
|---|---|---|---|
| ITIN | 9XX-XX-XXXX (starts with 9) | An individual with no SSN eligibility | IRS |
| SSN | NNN-NN-NNNN | An individual | Social Security Administration |
| EIN | XX-XXXXXXX | A business entity | IRS |
Why the ITIN Number Exists
The ITIN number exists because federal law requires an identifying number on tax filings. Under 26 U.S. Code § 6109, every person who files a return or statement must include an identifying number, and for individuals the default is the Social Security number. Because millions of people owe U.S. tax or must appear on a U.S. return yet cannot get an SSN, § 6109(i) authorizes the IRS to issue ITINs to them. The same subsection sets the modern expiration rule for ITINs issued after December 31, 2012 and allows applications in person, through certifying acceptance agents, or by mail.
Put plainly, the number is the plumbing that keeps the tax system inclusive. A foreign investor with U.S. rental income, a nonresident spouse on a joint return, and a dependent who lives abroad all create returns or reports the IRS must be able to file against a specific person. Without an alternative to the SSN, those filings would have no valid identifier. The ITIN number fills that gap so the obligation can be met and the record can be matched - nothing more. It is a compliance tool created by statute, not a benefit or a status.
Who Needs an ITIN Number
You need an ITIN number if you have a U.S. federal tax purpose and are not eligible for a Social Security number. The IRS issues ITINs to resident and nonresident aliens and to their spouses and dependents, regardless of immigration status. Common holders include:
- A nonresident alien who must file a U.S. return to report income or claim a treaty benefit;
- A resident alien who meets the substantial-presence test but cannot get an SSN;
- A nonresident spouse or dependent a U.S. taxpayer lists on a return;
- A foreign person who must be given a taxpayer ID for a withholding or information return.
You do not need an ITIN number if you already have an SSN or qualify for one - you use the SSN instead. And a business does not use an ITIN; it applies for an EIN. See how the individual numbers compare in ITIN vs. SSN.
How to Get an ITIN Number
You get an ITIN number by filing Form W-7, the only application for the number. You submit Form W-7 together with the federal tax return that creates your filing need and original documents proving identity and foreign status - a valid passport is the only stand-alone document the IRS accepts. Per the IRS application page, you can submit three ways: by mail to the IRS ITIN Operation in Austin, Texas; through a Certifying Acceptance Agent who authenticates your documents; or in person at an IRS Taxpayer Assistance Center by appointment. There is no IRS fee, and you should allow about 7 weeks for your number - 9 to 11 weeks in peak season or from abroad. The full walkthrough is in how to get an ITIN.
A few points matter for the number specifically. Most applicants must attach a completed federal return, though five exceptions in the Form W-7 instructions - covering certain passive income, scholarships and grants, mortgage interest, dispositions of U.S. real property, and specific corporate representatives - let some people apply without one. If you mail the application, you send original documents or issuing-agency certified copies, and the IRS returns them, generally within 60 days. If you use a Certifying Acceptance Agent or a Taxpayer Assistance Center, staff authenticate most documents in person so you keep your passport. Once assigned, the number arrives by mail in an IRS notice, and you place it on every federal return and tax document that calls for a taxpayer identifying number.
What an ITIN Number Does Not Do
An ITIN number is narrower than it looks. The IRS is explicit that an ITIN does not authorize you to work in the United States, does not provide or change your immigration status, does not qualify you for Social Security benefits, does not qualify you for the Earned Income Tax Credit, and does not serve as identification outside the federal tax system. In other words, the number does exactly one thing - it identifies you on a federal tax filing. It should never be presented as proof of work authorization or as a general-purpose ID.
The Earned Income Tax Credit is the clearest example of the limit. To claim the EITC, the IRS requires a valid Social Security number for the taxpayer, the spouse on a joint return, and any qualifying child - an ITIN number never satisfies that test. ITIN filers may still qualify for certain other tax benefits depending on their circumstances, but the EITC and Social Security retirement credits are tied to a work-eligible SSN. Because the ITIN number is not proof of work authorization or immigration status, presenting it to an employer as if it were an SSN does not make employment lawful; that role belongs to a Social Security number issued to a citizen or a DHS-authorized worker.
ITIN Number Expiration
An ITIN number is not permanent. Under the IRS rules, an ITIN not used on a U.S. federal tax return for three consecutive tax years expires on December 31 after that third year of non-use, mirroring the statutory rule in § 6109(i) for numbers issued after 2012. You renew an expired ITIN by filing Form W-7 again and checking "Renew an existing ITIN." Expired ITINs can still be used on information returns such as Form 1099, so you renew only when the number will appear on your own income tax return. See how to renew an expired ITIN for the timing and steps.
The number itself does not change when you renew - you keep the same nine digits, and the renewal simply reactivates them for filing. That is why the "renew an existing ITIN" box matters: it tells the IRS to refresh the number you already hold rather than assign a new one. A holder who files every year never triggers the three-year clock, so the number stays active indefinitely. A holder who stops filing lets it lapse, then reactivates the same number when a new obligation arises. Because renewals run through the same roughly 7-week processing window as a first-time application, it is worth confirming the number is active before you rely on it at filing time.
Examples of ITIN Number Holders
These short scenarios show who carries an ITIN number:
- Foreign investor. A resident of another country earns U.S. rental income and files Form 1040-NR, using an ITIN number because no SSN is available.
- Nonresident spouse. A U.S. citizen files jointly with a nonresident spouse, who gets an ITIN number to be identified on the return.
- Dependent abroad. A resident alien claims a dependent who is not eligible for an SSN; the dependent needs an ITIN number to be listed.
- Founder without an SSN. A non-U.S. founder uses an ITIN number as the responsible party on a business EIN application - see can you get an EIN without an SSN.
In every one of these cases the ITIN number does the same single job: it identifies a specific person on a federal tax filing so the IRS can process the return or report. The investor's rental income, the spouse's place on a joint return, and the dependent's listing all require a valid identifier, and the ITIN supplies it without conferring work authorization, immigration status, or benefits. That consistency is the point of the number - one nine-digit value, starting with 9, that means "this individual, for tax purposes" and nothing beyond it.
Frequently Asked Questions
What is an ITIN number?
An ITIN number is an Individual Taxpayer Identification Number - a 9-digit IRS tax processing number for people who need a U.S. taxpayer ID but are not eligible for a Social Security number. It is used only inside the federal tax system.
What does an ITIN number look like?
It is nine digits, formatted like an SSN as 9XX-XX-XXXX, and always begins with 9. That leading 9 distinguishes it from an SSN.
How do I get an ITIN number?
File Form W-7 with your federal tax return and proof of identity and foreign status. Submit by mail to Austin, Texas, through a Certifying Acceptance Agent, or at an IRS Taxpayer Assistance Center. There is no IRS fee.
Is an ITIN number the same as an SSN?
No. The SSA issues SSNs; the IRS issues ITINs. An SSN can authorize work and benefits; an ITIN number is for tax filing only and never authorizes work or immigration status.
Can I work with an ITIN number?
No. The IRS states an ITIN does not authorize work, does not change immigration status, and does not qualify you for Social Security benefits or the EITC. It exists only for tax filing.
Does an ITIN number expire?
Yes. An ITIN not used on a federal return for three consecutive years expires on December 31 after the third year. You renew it by filing Form W-7 and checking "Renew an existing ITIN."
Related Terms
- What is an ITIN? - the fuller explainer and legal basis.
- How to get an ITIN - the step-by-step Form W-7 process.
- ITIN vs. SSN - how the two individual numbers differ.
- ITIN renewal - how to renew an expired ITIN number.
- Can you get an EIN without an SSN? - using an ITIN as responsible party.
- How to get an EIN - the business tax ID process.
- ITIN (glossary) - the one-line definition.
- How to form an LLC - the formation hub tying these IDs together.
Sources
- IRS - Individual Taxpayer Identification Number (definition, 9-digit tax processing number, issued regardless of status, what it does not do).
- IRS - Taxpayer Identification Numbers (TIN) (ITIN begins with 9, format 9XX-XX-XXXX, tax processing number, no EITC).
- IRS - About Form W-7 (the application for the ITIN number).
- IRS - How to apply for an ITIN (three submission methods, Austin operation, 7-week and 9-11-week processing).
- IRS - Instructions for Form W-7 (passport as stand-alone document, return requirement and exceptions).
- IRS - How to renew an ITIN (three-year non-use expiration, information-return exception, renewal steps).
- IRS - Employer Identification Number (EIN identifies a business, two-digit prefix context).
- IRS - About Form SS-4 (a business applies for an EIN, not an ITIN).
- IRS - Who qualifies for the EITC (valid SSN required; ITIN does not qualify).
- IRS - About Form 1040-NR (nonresident return that carries an ITIN number).
- IRS - Form W-7 (PDF) (application-type and reason boxes).
- Cornell Legal Information Institute - 26 U.S. Code § 6109, Identifying numbers (statutory basis; § 6109(i) ITIN provisions and expiration).
LegalGlass provides general information for educational purposes and is not a law firm or a substitute for advice from a licensed attorney or tax professional. This page is information, not advice. Laws, forms, and processing times change; verify current requirements with the IRS before acting.