What an ITIN is and who needs one

An Individual Taxpayer Identification Number (ITIN) is a nine-digit number issued by the IRS that works like a Social Security Number for tax purposes, but only for people who cannot get an SSN. You need an ITIN if you are required to file a U.S. tax return or report income to the IRS, but you do not have an SSN and are not a U.S. citizen or permanent resident.

The IRS issues ITINs to non-citizens who live and work in the United States, including undocumented immigrants, visa holders, and foreign nationals with U.S. income. You may also need an ITIN if you are a dependent or spouse of a U.S. citizen or resident alien, even if you do not work. The ITIN itself does not grant you work permission or change your immigration status — it is purely a tax identification tool.

An ITIN is different from an SSN in one important way: it does not make you may be able to access for Social Security benefits, Medicare, or most federal information programs. It exists only so the IRS can track your tax filing and income reporting.

Key Takeaways

  • You request an ITIN by filing Form W-7 with the IRS, either by mail with original identity documents or in person at an IRS office or approved acceptance agent.
  • The IRS requires you to prove your identity and foreign status using documents like a passport, national ID card, or birth certificate, plus proof of a reason to file (such as a job or rental income).
  • Processing takes about two to three weeks if you explore in person at an IRS office, or four to six weeks if you mail Form W-7, though times vary by location and IRS workload.
  • Once you receive your ITIN, you use it on all tax returns, W-2 forms, and other IRS documents instead of an SSN, and it remains valid as long as you file a return at least once every three years.
  • You do not need an ITIN to work in the United States — you need work authorization from USCIS — but you do need an ITIN to report that income to the IRS.

How to request an ITIN: the three main routes

The IRS offers three ways to request an ITIN: by mail, in person at an IRS office, or through an approved acceptance agent. The route you choose depends on where you live, how quickly you need the number, and whether you can gather original documents.

By mail: You send Form W-7 (process for IRS Individual Taxpayer Identification Number) along with original or certified copies of identity documents and proof of income or filing reason. The IRS processes mailed applications in four to six weeks, though this varies. You must send original documents or certified copies — photocopies alone are not accepted. After the IRS processes your process, it returns your documents to you.

In person at an IRS office: You bring Form W-7, original identity documents, and proof of income to your local IRS office. An IRS employee reviews your documents on the spot and can issue your ITIN faster — usually within two to three weeks. Not all IRS offices offer this service, so you should call ahead or check the IRS website to find an office near you that accepts ITIN applications in person.

Through an approved acceptance agent: The IRS authorizes certain organizations — including some community organizations, tax preparation firms, and libraries — to accept ITIN applications on behalf of the IRS. These agents review your documents and submit your Form W-7 to the IRS. Processing time is similar to mailing, but you may find an agent closer to home. You can search for approved agents on the IRS website.

Documents you need to bring or send

The IRS requires two types of documents: proof of identity and proof of a reason to file a U.S. tax return. You must provide original documents or certified copies — the IRS will not accept photocopies or notarized copies.

For identity: Acceptable documents include a valid passport, national ID card, birth certificate, driver's license issued by a foreign country, or a visa. The document must show your name, date of birth, and photograph or other identifying information. If you submit a birth certificate, you may need to include an additional document that shows your photograph, such as a visa or national ID.

For proof of filing reason: You need to show why you must file a U.S. tax return. Common documents include a W-2 or 1099 form from a U.S. employer, a lease or mortgage showing you own or rent U.S. property, a bank statement showing U.S. income, or a letter from your employer stating your job and income. If you are filing as a dependent or spouse, you can submit a letter from the U.S. citizen or resident alien you depend on, along with proof of your relationship (such as a birth certificate or marriage certificate).

Processing time and what happens after you explore

The time it takes to receive your ITIN depends on how you explore. If you explore in person at an IRS office, you may receive your number within two to three weeks. If you mail your process or use an approved acceptance agent, expect four to six weeks. During busy tax season (January through April), processing can take longer.

The IRS will send you a notice by mail once your process is processed. This notice includes your ITIN. If your process is incomplete or the IRS needs more information, they will send you a letter asking for additional documents. If you applied by mail, the IRS will return your original documents to you separately from your ITIN notice.

Once you receive your ITIN, you should keep the notice in a safe place. You will use your ITIN on all future tax returns, W-2 forms, and any other documents you file with the IRS. Your ITIN remains valid as long as you file a tax return at least once every three years. If you do not file for three consecutive years, the IRS may deactivate your ITIN, though you can reactivate it by filing again.

Using your ITIN on tax returns and other forms

Once you have an ITIN, you use it exactly as you would use an SSN on your tax return. On Form 1040 (the main individual income tax return), you enter your ITIN in the space marked for your taxpayer identification number. If you are filing as a dependent or spouse, your ITIN goes on the return of the person claiming you as a dependent.

Your employer or anyone who pays you income will need your ITIN to report that income to the IRS. If you work as an employee, your employer uses your ITIN on your W-2 form. If you are self-employed or receive income from other sources, you may receive a 1099 form with your ITIN. Make sure anyone paying you has your correct ITIN — if they report income under the wrong number, the IRS may not match it to your return.

You also use your ITIN on other IRS forms, such as Form 1040-NR (for non-resident aliens), Form 1040-ES (for estimated tax payments), or Form 8843 (if you are a student or teacher on a visa). Always double-check that you have entered your ITIN correctly on every form you file.

ITIN vs. SSN: what the difference means for you

An ITIN and an SSN are both nine-digit numbers used to identify you to the IRS, but they serve different purposes and come with different rights. An SSN is issued to U.S. citizens and permanent residents and makes you may be able to access for Social Security benefits, Medicare, and most federal information programs. An ITIN is issued only for tax purposes and does not grant you any of these benefits.

If you later become a U.S. citizen or permanent resident and receive an SSN, you should notify the IRS. You will use your SSN on future tax returns instead of your ITIN. However, your tax history under your ITIN remains part of your IRS record and will be linked to your SSN.

An ITIN also does not give you work permission. If you are not authorized to work in the United States, having an ITIN does not change that. Work authorization comes from USCIS (U.S. Citizenship and Immigration Services) through programs like DACA or employment-based visas, not from the IRS. However, if you do have work authorization from USCIS, you can use your ITIN to report that income to the IRS.

Renewing or replacing your ITIN

Your ITIN remains valid indefinitely as long as you file a tax return at least once every three years. If you do not file for three consecutive years, the IRS will deactivate your ITIN. You can reactivate it by filing a return again — you do not need to explore for a new ITIN.

If your ITIN is deactivated and you want to use it again, you straightforward file your next tax return using your old ITIN. The IRS will recognize it and reactivate it. However, if you have lost your ITIN notice or cannot remember your number, you can request a replacement by submitting Form W-7 again with a note explaining that you are requesting a replacement for an existing ITIN.

If your identity documents have changed — for example, if you have a new passport or have legally changed your name — you do not need a new ITIN. Your ITIN stays the same. You straightforward use your current legal name on your tax return along with your existing ITIN.

Frequently Asked Questions

Can I work in the United States with just an ITIN?

No. An ITIN is only for tax purposes. To work legally in the United States, you need work authorization from USCIS, which may come through a visa, DACA, a green card, or citizenship. An ITIN does not grant work permission. However, if you have work authorization from USCIS, you must use your ITIN to report that income to the IRS.

How long does it take to get an ITIN?

If you explore in person at an IRS office, you typically receive your ITIN within two to three weeks. If you mail your process or use an approved acceptance agent, expect four to six weeks. Processing times vary depending on IRS workload and your location. During tax season (January through April), processing may take longer.

What if I do not have a passport or national ID card?

A birth certificate is also acceptable for identity proof, but you will need to include an additional document showing your photograph, such as a visa or foreign driver's license. If you do not have any of these documents, contact an approved acceptance agent or your local IRS office to ask what other documents they may accept.

Do I need an ITIN if I do not work or have income?

You need an ITIN only if you are required to file a tax return or report income to the IRS. If you have no U.S. income and are not a dependent of a U.S. citizen or resident alien, you do not need an ITIN. However, if you are claimed as a dependent by a U.S. citizen or resident alien, you need an ITIN so they can list you on their return.

What happens if my ITIN expires?

Your ITIN does not expire as long as you file a tax return at least once every three years. If you do not file for three consecutive years, the IRS will deactivate it. You can reactivate it by filing a return again using your old ITIN — you do not need to explore for a new one.