Tax identification numbers
ITIN vs SSN vs EIN: which number do you need?
All three are nine-digit U.S. tax numbers, which is why they get mixed up. They identify different things: an SSN and an ITIN identify a person, an EIN identifies a business.
The short version
If you are eligible for a Social Security number, that is your tax number and you do not need an ITIN. If you are not eligible and still have to file, you need an ITIN. If you are setting up a business that has to file its own returns, hire employees or open accounts in the company name, that business needs an EIN, whichever personal number you hold.
- SSN — issued by the Social Security Administration, identifies a person, and goes with work authorization.
- ITIN — issued by the IRS, identifies a person who must file but cannot get an SSN. No work authorization, no Social Security benefits, no Earned Income Tax Credit.
- EIN — issued by the IRS, identifies a business or other entity. Free, and you never have to pay a fee for one.
ITIN vs SSN
These two are alternatives, not a pair: the ITIN exists precisely for people who are not eligible for an SSN. The IRS issues an ITIN for federal tax purposes only, and it says so in three specific ways — an ITIN does not authorize work, does not qualify you for Social Security benefits, and does not make you eligible for the Earned Income Tax Credit.
If your situation changes and you become eligible for an SSN, the SSN becomes the number you use. You do not keep filing on the ITIN because you have always used it.
ITIN vs EIN
This is the pair people really do need both of. An ITIN identifies you; an EIN identifies your company. A non-resident who owns a U.S. LLC commonly ends up with an EIN for the LLC and an ITIN for themselves, because the company files and so do they.
They are also obtained differently. An EIN application asks for a responsible party’s SSN or ITIN, and applicants whose principal place of business is outside the United States cannot use the online tool — the IRS directs them to apply by phone, fax or mail instead.
Which one your situation needs
Work down this list; most people land on the first or second line.
- Eligible for an SSN: use the SSN. No ITIN.
- Must file a U.S. return, not eligible for an SSN: ITIN, on Form W-7.
- Spouse or dependent claimed for an allowable tax benefit, not eligible for an SSN: ITIN.
- Forming a company, hiring, or opening business accounts: EIN for the company.
- Non-resident with a U.S. LLC: usually an EIN for the company and an ITIN for yourself.
What each one costs
An EIN is free, and the IRS warns in its own words to beware of websites that charge for one. There is no IRS fee to apply for an ITIN on Form W-7 either; what people pay for is help preparing the return and the application, or a service that verifies documents so originals do not have to be mailed.
Not sure which number you need?
USTAXX works with immigrant founders and non-resident owners every week: the company’s EIN, your ITIN and the return they belong to, handled together.
Questions people ask
Is an ITIN the same as an EIN?
No. An ITIN identifies an individual for federal tax purposes; an EIN identifies a business or other entity. A non-resident with a U.S. company often needs both.
Can I use my ITIN instead of an EIN for my business?
Not where the business itself needs a number. The IRS says you generally need an EIN to hire employees, operate a partnership or corporation, pay certain taxes or change business structure.
Can I get an EIN without an SSN or ITIN?
The IRS online tool asks for the responsible party’s SSN or ITIN. Applicants whose principal place of business is outside the United States are directed to apply by phone, fax or mail instead of online.
I have an ITIN and just got an SSN. What now?
The SSN becomes your tax number going forward. Tell the IRS so your records and prior filings can be linked to it, and stop filing under the ITIN.
Do I need an ITIN if I only have an extension to file?
Not for the extension itself. The IRS says an ITIN is not needed for an extension on Form 4868 or for estimated payments on Form 1040-ES or 1040-ES (NR).
Where these rules come from
- IRS: Individual Taxpayer Identification Number
- IRS: Get an Employer Identification Number
- IRS: Instructions for Form W-7
General information, current when written, not advice about your situation. Fees and forms change; the official pages above are the authority.