ITIN vs SSN vs EIN: which US tax ID do you need?

ITIN vs SSN vs EIN at a glance

If you're forming a US LLC from outside the US, start with the EIN. See how to get an EIN without an SSN or ITIN.

EIN: the tax ID for your LLC

An Employer Identification Number (EIN) is a 9-digit number, written like 12-3456789, that the IRS assigns to businesses and other entities. The IRS lists LLCs among the entities that need one, and a single-member LLC owned by a foreign person must use its own name and EIN to file Form 5472. Banks ask for it too, and the IRS says you can use a new EIN right away to open a bank account.

The online application needs the responsible party's SSN or ITIN. Without one, you file Form SS-4 by fax or mail, or by phone at 267-941-1099 if your business is based outside the US. The IRS doesn't charge for an EIN.

An EIN is for business use only, and the IRS says not to use it in place of an SSN or ITIN. If you no longer need it, the IRS can deactivate the number, but it can't cancel it.

SSN: only if you can live or work in the US

A Social Security number (SSN) is issued by the Social Security Administration, not the IRS. According to the IRS, you're eligible for one if you're a US citizen or have been admitted to the US for permanent residence or US employment. You apply with Form SS-5 and evidence of your identity, age and US citizenship or lawful alien status, and there's no fee.

Owning or running a US company isn't one of those grounds, so a founder living abroad generally can't get an SSN for the LLC. If you do have an SSN, or are eligible for one through a US work visa, use it. The IRS won't issue an ITIN to someone who is eligible for an SSN, and you shouldn't file Form W-7 while an SSN application is pending.

ITIN: for individuals with a US tax filing need

An Individual Taxpayer Identification Number (ITIN) is a 9-digit number beginning with 9 that the IRS issues to people who need a US taxpayer ID but aren't eligible for an SSN. It's for federal tax purposes only: it doesn't authorize you to work in the US, give you immigration status or qualify you for Social Security benefits.

You need one when you have a federal tax purpose, such as being required to file a US tax return, claiming a refund or other tax benefit, or claiming certain treaty benefits.

How to apply with Form W-7

1. 1

   Pick your reason

   Check the box that fits. A non-resident filing a US tax return checks box b. A non-resident claiming a treaty benefit checks box a, plus box h with the exception that applies.

2. 2

   Attach your tax return

   Most applications must include the federal tax return you need the ITIN for, such as Form 1040-NR. Five exceptions, such as third-party withholding on passive income, let you apply without a return if you send the documents that exception requires.

3. 3

   Prove your identity and foreign status

   A valid passport is the only document that proves both on its own. Otherwise, send at least two documents from the IRS list. They must be originals or copies certified by the issuing agency, and not expired.

4. 4

   Submit the package

   Mail it to Internal Revenue Service, Austin Service Center, ITIN Operation, P.O. Box 149342, Austin, TX 78714-9342, or use a Certifying Acceptance Agent in the US or abroad, who can check most documents and hand them straight back. In the US, some IRS Taxpayer Assistance Centers do this for free by appointment.

5. 5

   Wait for the IRS notice

   Allow 7 weeks, or 9 to 11 weeks if you apply between January 15 and April 30 or from outside the US. Mailed originals come back to the address on your W-7; call the IRS if they aren't back within 60 days.

On September 11, 2026, the IRS processing status page showed it working on Forms W-7 received in August 2026. If you'll need your passport within 60 days, the IRS suggests applying in person or through a Certifying Acceptance Agent instead of mailing the original.

Keeping an ITIN active

An ITIN expires if it isn't used on a US federal tax return for 3 consecutive tax years, on December 31 of the third year. You only need to renew it when it will go on a tax return, using the same Form W-7. You also can't e-file a return with an ITIN in the calendar year the IRS issues it.

Do you need an ITIN to run a US LLC from abroad?

Often not. The core steps of owning a US LLC from abroad work without one:

• Getting the EIN: Form SS-4 lets a responsible party without an SSN or ITIN write “foreign” on line 7b.
• Filing Form 5472: the LLC can report you with a reference ID number and your foreign tax ID, or “None”. See Form 5472 for foreign-owned US LLCs.
• Giving a US client Form W-8BEN: certain treaty claims need a tax ID, but your foreign tax ID can be used instead of an SSN or ITIN.

You're likely to need an ITIN when:

• Your LLC is engaged in a US trade or business, so you must file Form 1040-NR. See US taxes for non-resident LLC owners.
• You're a foreign member of a multi-member LLC that's engaged in a US trade or business. The IRS says such a partner must file a US return and have an ITIN.
• US tax was withheld from your income and you want a refund, which means filing a return.

Banks and payment providers set their own ID requirements, which can differ from the IRS's. See opening a US bank account as a non-resident and Stripe for a US LLC before you apply.

How we help with your tax IDs

Starter ($349 a year plus the state fee) includes your LLC's EIN with or without an SSN: we prepare and file Form SS-4 when you don't have an SSN or ITIN. Pro ($999 a year plus the state fee) applies for the EIN by phone as your designee and adds Form 5472 with the pro forma 1120, prepared by our US tax partner. Compare both on the pricing page.

For an ITIN, the IRS works with Certifying Acceptance Agents in the US and abroad, and some of them also prepare the tax return itself. Their fees vary.

Frequently asked questions