An ITIN (individual taxpayer identification number) is a 9-digit number the IRS issues to people who need a US taxpayer number for federal tax purposes but aren't eligible for a Social Security number. You apply with Form W-7, usually sent together with your US tax return.
If you're a freelancer, creator or business owner outside the US, this is the number that comes up when you need to file a US return or claim a tax treaty benefit. It's issued for federal tax purposes only, and it isn't a work permit.
Who needs an ITIN
The IRS says you need an ITIN if you have a federal tax purpose and you're not eligible for an SSN. The common cases are:
- Nonresident aliens who must file a US tax return
- Nonresident aliens claiming a tax treaty benefit where an ITIN is required
- Resident aliens who can't get an SSN
- Spouses and dependents of US citizens or resident aliens, so they can be included on a return
- Some people with passive income subject to third-party withholding
The IRS also says you can apply regardless of immigration status. What you can't do is get an ITIN if you qualify for an SSN, which is why someone on a US work visa is told to get an SSN instead.
What an ITIN doesn't do
| Myth | What the IRS says |
|---|---|
| It lets me work in the US | An ITIN doesn't change your immigration status or your right to work in the United States |
| It gets me Social Security | An ITIN doesn't entitle you to Social Security benefits |
| I need it before I can ask for more time | You don't need an ITIN to apply for an extension of time to file |
| I need it to pay estimated tax | You don't need an ITIN to make estimated tax payments |
| Everyone with US income needs one | A return with all zero entries generally doesn't show a federal tax purpose, so you wouldn't need to file or apply |
How to apply for an ITIN
- Complete Form W-7, Application for IRS Individual Taxpayer Identification Number, and tick the reason that applies to you.
- Attach your federal tax return, unless you meet one of the exceptions in the W-7 instructions. The IRS says to include the return in the application package, not file it separately.
- Include proof of identity and foreign status: original documents or copies certified by the issuing agency.
- Send it by mail, or apply in person at an IRS Taxpayer Assistance Center with ITIN services, or through a Certifying Acceptance Agent or Acceptance Agent.
- Apply on or before your tax return due date, and allow time for the IRS to reply.
The in-person routes matter if you don't want to post your passport. The IRS says Taxpayer Assistance Centers can authenticate all documents for applicants who appear in person, except school and medical records for dependents, and that applying at a centre in the US is free. It also warns it may take several weeks to get an appointment.
Which documents count
The W-7 instructions list 13 acceptable documents. The passport is the only stand-alone document, meaning it proves both identity and foreign status on its own. Anything else has to be combined. One catch for families: a passport without a US date of entry won't be accepted as a stand-alone document for certain dependents.
How long it takes
The IRS says to allow 7 weeks to hear about your application, or 9 to 11 weeks during tax season (15 January to 30 April) or if you applied from overseas. If you posted original documents and haven't had them back within 60 days, contact the IRS.
After it's issued
The IRS sends your number with a CP565 notice. Keep it with your tax records, because if you lose it you'll need to contact the IRS to confirm the number. If you later get a Social Security number, stop using the ITIN and tell the IRS, by mail or at a local IRS office, so it can combine your records under the SSN. The IRS warns that if you don't, you may not get credit for all the wages paid and tax withheld. And for a renewal, the IRS treats the assignment date as the original date the ITIN was first issued, not the renewal date.
When an ITIN expires
This is the rule most people don't know. If you don't use your ITIN on a federal tax return for any 3 consecutive tax years, it expires on 31 December after the third year of non-use. You must renew it with a new Form W-7 if it'll be on a return again, although expired ITINs can still be used on information returns. The instructions add that an ITIN assigned before 2013 that was never renewed needs a renewal application too.
ITIN versus a W-8BEN
Many non-US freelancers only need to give a US client or platform a W-8BEN, not file a return. My guides to the W-8BEN for India and the W-8BEN for the Philippines explain that side. You only need an ITIN on that form if a treaty claim or US filing requires one.
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My verdict
Don't apply for an ITIN just in case. Get one when you have a real US filing or treaty reason, send it with your return, and use a Taxpayer Assistance Center or Acceptance Agent if you'd rather not post your passport. Then put a note in your diary: if three tax years pass without using it, it'll lapse. If you're chasing remote US work, my guide on applying for US remote jobs from abroad covers the hiring side.
Frequently asked questions
What is an ITIN number?
An ITIN is a 9-digit number the IRS issues to people who need a US taxpayer identification number for federal tax purposes but aren't eligible for a Social Security number.
How do I get an ITIN?
Complete Form W-7 and send it with your federal tax return and identity documents by mail, or apply in person at an IRS Taxpayer Assistance Center or through an Acceptance Agent.
How long does it take to get an ITIN?
The IRS says to allow 7 weeks, or 9 to 11 weeks during tax season or if you applied from overseas.
Does an ITIN expire?
Yes. If it isn't used on a federal tax return for any 3 consecutive tax years, it expires on 31 December after the third year of non-use.
Can I work in the US with an ITIN?
No. An ITIN doesn't change your immigration status or your right to work in the United States.
What documents do I need for an ITIN?
Original documents or copies certified by the issuing agency that prove identity and foreign status. A passport is the only stand-alone document.
