A US tax number for you, when the IRS rules call for one.

The IRS says: "An ITIN is issued by the IRS for federal tax purposes only." It is a 9-digit number for someone who needs a US taxpayer identification number and isn't eligible for a Social Security number. The IRS adds that an ITIN doesn't serve as identification outside the federal tax system, and doesn't authorize work in the US.

In the IRS's words: "You need an ITIN if you have a federal tax purpose and you’re not eligible for an SSN." You have one when you are legally required to file a US federal income tax return, want to claim a refund or tax benefit by filing one, can be claimed as a spouse or dependent for an allowable tax benefit, or must give a tax number for another federal tax purpose.

Your company's own number is the EIN. The EIN comes with formation, or on its own for an LLC you already have.

The Form 1040-NR instructions for 2025 list who must file that return. The first case reads: "You were a nonresident alien engaged in a trade or business in the United States during 2025. You must file even if:" no income from a trade or business conducted in the US, "You have no U.S. source income", or income exempt from US tax under a tax treaty or the Internal Revenue Code.

An owner who files a 1040-NR and can't get an SSN applies for the ITIN with that return. Form W-7 reason box b covers "A nonresident alien who must file a U.S. federal tax return to report income effectively or not effectively connected with the conduct of a trade or business in the United States". The W-7 instructions add: "If you’re required to file a federal tax return, then you aren’t eligible for Exception 1."

IRS Publication 519 says: "Whether you are engaged in a trade or business in the United States depends on the nature of your activities." It also says: "If you own and operate a business in the United States selling services, products, or merchandise, you are, with certain exceptions, engaged in a trade or business in the United States." A member of a partnership engaged in a US trade or business is treated as engaged in one too. For an online seller, the answer turns on the facts. Does my LLC owe US income tax? sets out the IRS examples, and your written quote starts from your own facts.

Most new ITIN applications go with the US federal tax return the number is needed for: Form W-7 is attached to the front of that return. The W-7 instructions also list exceptions, and an application under one of them is sent without a return, with the documents that exception's table lists.

• Exception 1. Passive income subject to third-party withholding or tax treaty benefits, such as interest, rental or partnership income reported on Form 1042-S, Form 8805 or Schedule K-1 (Form 1065). It is closed to anyone who must file a federal tax return.
• Exception 2. Other income where you claim a US tax treaty benefit, such as wages or honoraria, or receive taxable scholarship or grant income.
• Exception 3. Mortgage interest on US real property you own, reported by the lender.
• Exception 4. A sale of US real property by a foreign person, subject to withholding by the buyer.
• Exception 5. A non-US representative of a foreign corporation who needs an ITIN to meet an IRS e-filing requirement under T.D. 9363.

We prepare W-7 packages under an exception now. If your application must go with a US tax return, such as Form 1040-NR, your quote says how we handle it.

1. 01

   Tell us your reason

   Say what the ITIN is for and whether a US tax return goes with it. We check it against the IRS's federal tax purposes, free, and reply with a written quote.

2. 02

   We prepare your package

   Form W-7 for each person applying, with the documents your reason calls for and your passport route set out. Your quote gives the date it is ready.

3. 03

   You sign and send it

   You sign and post the package, or take it to an IRS Certifying Acceptance Agent, who checks your passport and sends it on.