ITIN vs SSN: what’s the difference?

ITIN vs SSN at a glance

The short version: an SSN is for US citizens, permanent residents and people allowed to work in the US, and an ITIN is a tax-only number for people who can’t get an SSN.

Who can get an SSN

The Social Security Administration can assign an SSN to US citizens, to noncitizens admitted for permanent residence, and to noncitizens whose immigration status lets them work in the US. Applying is free.

Noncitizens without work authorization can get an SSN only for what the regulation calls a “valid nonwork reason”. That means a federal law requires an SSN for a federally funded benefit they’re already entitled to, or a state or local law requires one for public assistance and they’re in the US legally. Cards issued this way carry a legend such as “Not valid for employment”; others say “Valid for work only with DHS authorization”.

The Social Security Administration’s own manual lists reasons it won’t accept for a nonwork SSN, including taxes, bank accounts and driver’s licenses. For taxes, it points people to the ITIN.

Who needs an ITIN instead

You need an ITIN if you have a federal tax reason to need a US taxpayer number and you aren’t eligible for an SSN. The IRS gives these examples:

• a nonresident who must file a US tax return, or files one to claim a refund
• a nonresident claiming a tax treaty benefit, for example on a withholding certificate
• a resident alien under the days-present test who files a return but can’t get an SSN
• a spouse or dependent claimed on a US return for an allowable tax benefit
• a nonresident student, professor or researcher who files a return

If you’re eligible for an SSN, you can’t get an ITIN. The IRS says people with a US work visa don’t need an ITIN, because they qualify for an SSN. If you have an SSN application pending, don’t apply for an ITIN; if the Social Security Administration turns you down, you attach its denial letter to your Form W-7. How to apply for an ITIN covers the rest of the process.

What you can and can’t do with an ITIN

An ITIN lets you meet your US tax obligations. With one, you can:

• file US federal tax returns and claim refunds of tax withheld from your income
• claim a lower treaty rate of US withholding on Form W-8BEN, where a US tax number is required
• be claimed as a spouse or dependent for allowable tax benefits, such as the credit for other dependents
• give banks and other payers the number they ask for to file their tax reports about you

The IRS is clear about the limits. An ITIN doesn’t:

• authorize you to work in the US
• qualify you for Social Security benefits or the Earned Income Tax Credit
• let you claim the child tax credit, which needs an SSN valid for work
• provide or change your immigration status
• serve as identification outside the federal tax system

For more on what the number is and who it’s for, see what is an ITIN.

Can you have both an ITIN and an SSN?

No. The IRS says you can’t have both. It won’t issue an ITIN to someone who already has an SSN, and once you get an SSN you must stop using your ITIN.

Use the SSN on your tax returns from then on, even if your card says it isn’t valid for employment. The same goes if your SSN once authorized work and you later lost that permission.

Got an SSN later? Stop using the ITIN

If you become eligible for an SSN, for example after getting permanent residence or permission to work, the IRS asks you to switch over and tell it, so it can merge your records.

1. 1

   Apply for the SSN

   Apply to the Social Security Administration on Form SS-5. Your ITIN doesn’t convert; the SSN is a separate application.

2. 2

   Stop using the ITIN

   Use the SSN on every federal tax return and tax form from now on.

3. 3

   Write to the IRS

   Say you’ve been assigned an SSN and want your tax records combined. Include your full name, mailing address, ITIN (with a copy of your CP565 notice if you have it) and a copy of your Social Security card. Mail it to Internal Revenue Service, Austin, TX 73301-0057, or visit a local IRS office.

4. 4

   Let the IRS merge your records

   The IRS voids the ITIN and moves everything filed under it to your SSN. If you skip this, you may not get credit for all the wages and tax withheld under the ITIN, which can shrink a refund.

5. 5

   Update your payers

   Give your SSN to the banks, platforms and other payers that report your income, so their tax forms use the new number.

Which number to use on tax forms and applications

Use one number: your SSN if you have one, otherwise your ITIN. On a tax return, the ITIN goes in the box labeled for the SSN.

• Form W-8BEN. Non-US individuals give this form to US payers to confirm foreign status and claim treaty rates. Line 5 asks for a US tax number (SSN or ITIN) when one is required. To claim treaty benefits you generally need an ITIN unless you give your home country’s tax number on line 6 instead. Read more in our guides to Form W-8BEN and foreign tax ID numbers.
• Business accounts. A company or other business entity has its own number, the EIN. ITIN vs EIN explains when you need which.
• Payment platforms. PayPal, Stripe and marketplaces collect tax information from you, and each decides which numbers it accepts. Our pages on PayPal and Stripe cover what each asks for.