An ITIN (Individual Taxpayer Identification Number) is a US tax number for people who need one but cannot get a Social Security number. Non-residents usually need it to file a US tax return or claim a treaty benefit. This guide walks through who qualifies, what to send and how long it takes.
What an ITIN is (and isn’t)
An ITIN is a nine-digit number that starts with 9. The IRS issues it only for federal tax purposes. It does not give you the right to work in the US, it is not immigration status, and it does not make you eligible for Social Security benefits.
You do not need an ITIN to form a US LLC or to get an EIN for your company. Many founders get one later, when they have a personal US tax filing requirement. Check quickly with our free ITIN eligibility checker.
ITIN vs SSN vs EIN
| Number | Who it’s for | Used for |
|---|---|---|
| SSN | People authorized to work in the US | Work, tax returns, Social Security |
| ITIN | Individuals who need a US tax number but can’t get an SSN | Federal tax returns and treaty claims only |
| EIN | Businesses, including LLCs owned by non-residents | The company’s taxes, banking and payment platforms |
A common mix-up: your LLC needs an EIN, while you personally may or may not need an ITIN.
Who needs an ITIN?
You may need an ITIN if you are not eligible for an SSN and you:
- Must file a US federal tax return, for example a non-resident with US-source income who files Form 1040-NR;
- Want to claim a tax treaty benefit or a refund of tax withheld;
- Are the spouse or dependent of a US citizen or resident and are listed on their return; or
- Fall under one of the IRS exceptions, such as certain bank, investment or treaty situations.
The documents you need
- Form W-7, completed for each person applying.
- A federal tax return (Form 1040 or 1040-NR) that needs the ITIN, unless you qualify for an exception. The ITIN fields on the return are left blank.
- Proof of identity and foreign status. A valid passport is the only document that proves both on its own. Without a passport, you need at least two other documents from the IRS list (for example a national ID card and a birth certificate).
Documents must be originals or copies certified by the agency that issued them. Ordinary notarized photocopies are not accepted. That is why the way you apply matters.
Filling in Form W-7: the key choices
The most important part of Form W-7 is the box at the top for your reason for applying. The common ones are:
- a: Non-resident alien who needs an ITIN to claim a tax treaty benefit.
- b: Non-resident alien filing a US federal tax return (the most common reason for founders and freelancers with US-source income).
- c: US resident alien filing a US federal tax return.
- d and e: Dependent or spouse of a US citizen or resident alien.
- f: Non-resident alien student, professor or researcher filing a return or claiming an exception.
- h: Other, used for certain exceptions with the supporting proof the instructions require.
The rest of the form asks for your name as it appears in your passport, your foreign address, date and country of birth, citizenship, foreign tax ID if you have one, and details of your US visa, if any. Every detail must match your documents.
Applying without a tax return
Some people need an ITIN before they have a return to file, for example to claim a reduced treaty rate on certain income or because a US bank or financial institution requires one for reporting. The IRS lists these situations as exceptions in the Form W-7 instructions, and each one needs specific proof, such as a letter from the payer. If you don’t clearly fit an exception, the application should be filed with your tax return.
Three ways to apply
1. By mail to the IRS. You send Form W-7, your tax return and your original passport (or certified copies) to the IRS ITIN Operation in Austin, Texas. The IRS returns original documents, but you are without your passport for weeks.
2. Through a Certifying Acceptance Agent (CAA). A CAA is authorized by the IRS to verify your passport and certain other documents, so you keep your originals. CAAs charge a fee, which varies.
3. In person at an IRS Taxpayer Assistance Center (TAC). Some IRS offices in the US verify documents for free by appointment. This only helps if you are in the US.
The IRS itself does not charge a fee for an ITIN.
How long does it take?
The IRS says to allow 7 weeks to hear about your application, and 9 to 11 weeks if you apply from abroad or during tax season (January 15 to April 30). Plan your tax return around this.
Common mistakes that cause rejections
- Choosing the wrong “reason for applying” box on Form W-7.
- Sending plain photocopies instead of originals or certified copies.
- Applying without the tax return or without proof of an exception.
- Names or dates that don’t match the passport exactly.
- Leaving out details the form asks for, such as your full foreign address or your US visa details if you have a visa.
ITIN expiry and renewal
An ITIN that is not used on a federal tax return for three tax years in a row expires on December 31 of the third year. If you need it again for a return, you renew it with a new Form W-7. See our ITIN renewal service.
After your ITIN arrives
The IRS sends a letter with your ITIN. Keep it safe; you will use the number on future returns and some US accounts ask for it. Our free ITIN guide explains what an ITIN can help with next, such as credit-building cards and online accounts that accept ITIN holders.
How Ze Filing helps
We check which reason applies to you, prepare Form W-7, review your documents before they go to the IRS and track the application. Our ITIN service is $149, or $189 together with your Form 1040-NR. Upload documents securely in your client portal or send them to us on WhatsApp.
Ze Filing is a private document-preparation service, not the IRS. You can apply for an ITIN directly with the IRS free of charge.