ITIN number vs SSN: which taxpayer number you need
ITIN number vs SSN is the difference between a tax-processing number from the IRS and a Social Security number from the Social Security Administration. You apply for an ITIN only when you have a US tax reason and you are not eligible for an SSN. You can't hold both.
By Alex Thomas · Founder of ITIN Club
Updated 5 min read
- Form W-7
- IRS
Ask members who've already done this.
- Who issues it
- IRS or Social Security
- ITIN format
- 9 digits, starts with 9
- Authorizes work
- SSN, not an ITIN
- If you never file
- ITIN can expire
Two different numbers
An ITIN and a Social Security number both have 9 digits, and you can type either one into the taxpayer-ID box on a federal return. That is where the overlap ends.
- Issued by the IRS, only for federal tax
- For a nonresident or resident alien, or their spouse or dependent, who can't get an SSN
- Does not authorize work, benefits, or an immigration status
- Issued by the Social Security Administration on Form SS-5
- For US citizens and people with lawful alien status, including people authorized to work
- The number you use for work, Social Security, and taxes if you are eligible for it
The IRS is direct about who should not apply for an ITIN: US citizens, permanent residents (green card holders), nonresidents with a US work visa, and anyone else who can get an SSN. If that is you, apply for the SSN.
ITIN number vs SSN, side by side
| ITIN | SSN | |
|---|---|---|
| Issued by | The IRS | The Social Security Administration |
| Who can get it | Someone with a US tax purpose who can't get an SSN | Citizens and people with lawful alien status who qualify |
| Format | 9 digits, always starting with 9. The 4th and 5th digits are in 50–65, 70–88, 90–92, or 94–99 | 9 digits, in the same NNN-NN-NNNN shape |
| Lets you work | No | Yes, when the card is valid for work |
| Social Security and the EITC | No. You can't claim the earned income credit with an ITIN | Social Security credits come from an SSN. The EITC also requires a valid SSN |
| Outside the tax system | Not valid ID, including for a state driver's license | Widely used as ID |
| Expires | Yes, after 3 tax years in a row with no federal return, on December 31 of that third year | No |
A number that starts with 9 is not automatically an ITIN. The IRS only treats it as a valid ITIN when those middle digits fall in the ranges above.
Which one you should get
- 1
Start with the SSN
If you are a US citizen, a green card holder, or here on a work visa, you are in the group the IRS tells not to apply for an ITIN. Request a Social Security number on Form SS-5. That application asks for proof of identity, age, and citizenship or lawful alien status.
- 2
Use an ITIN only for a tax reason
You need an ITIN when you must file a US return, claim a refund or an allowable tax benefit, be claimed as a spouse or dependent for an allowable benefit, or give a taxpayer ID for another federal tax purpose, and you can't get an SSN. Immigration status does not block the application. A return full of zeros usually does not show a tax purpose.
- 3
Don't collect both
You can't have both. If you get an SSN later, stop using the ITIN and write to the IRS so they combine your records under the SSN. They void the ITIN.
The full application, documents, and addresses are in how to get an ITIN. What the number does and doesn't allow is in what you can do with an ITIN.
Not sure which number fits?
Ask members who filed with an ITIN, and who was told to get a Social Security number instead.
Where each number works
- You enter an ITIN in the same box as an SSN on a federal return
- An ITIN does not qualify you for Social Security benefits or the earned income credit
- Some other credits are allowed. The IRS lists them on the ITIN page, with conditions
- An ITIN does not authorize employment
- An SSN is the taxpayer ID for people who are allowed to work
- A business uses an EIN, not either of these, for the company itself. See ITIN vs EIN
- Banks, card issuers, and lenders set their own rules. Many accept an ITIN in place of an SSN, and some don't
- Compare bank accounts, credit cards, and ITIN lenders
- The IRS will not issue an ITIN only so you can open a bank account or start a business
How you apply
- Eligible for an SSN: file Form SS-5 with the Social Security Administration, not Form W-7.
- Not eligible, and you have a federal tax reason: file Form W-7 with the IRS, with a return or the proof of an exception.
- You already have an ITIN and later get an SSN: stop using the ITIN and ask the IRS to combine the records.
- Your ITIN is expired and you need it on a return: renew it. The steps are in ITIN renewal.
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Questions
Who qualifies for an ITIN number?
Can I work in the US with an ITIN number?
Can you be undocumented with an ITIN?
Can a non-US citizen get an ITIN?
Can I use an ITIN instead of an SSN?
Are an ITIN and an SSN formatted the same way?
Sources
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