Requirements for filing taxes in the US if you are not a resident company

If your company is not domiciled in the United States and you need to register to collect and remit sales tax in an American state, you do not need to form a U.S. legal entity. Economic nexus obligations apply based on your sales volume or transaction count in each state, regardless of whether you have a physical or legal presence there.

Before starting the formal state registration, you need three things: a U.S. mailing address, a Federal Employer Identification Number (EIN), and a commercial bank account.

Step 1: Get a U.S. Mailing Address

States require a U.S. address to receive official correspondence and tax notices. You do not need a physical office.

A virtual mailbox service is the simplest option for non-resident companies. iPostal1 provides a real street address (not a P.O. box) in the U.S., forwards your mail digitally, and is widely accepted by state tax authorities.

Step 2: Obtain a Federal EIN

The Employer Identification Number (EIN) is your federal tax ID. It is required to register with state revenue departments.

Foreign companies can apply for an EIN without a U.S. entity by filing Form SS-4 directly with the IRS:

• Download Form SS-4 from the IRS website.
• Complete the form and submit it by fax, mail, or phone. International applicants cannot use the IRS online application.
• Processing takes 4 to 6 weeks by mail, around 4 business days by fax, or immediately by phone.

Once issued, your EIN does not expire and can be used for all state registrations.

For a step-by-step guide on filling in each field and choosing a submission method, see How to complete and submit Form SS-4 as a foreign company.

Step 3: Open a U.S. Commercial Bank Account

A U.S. bank account is needed to manage tax payments and remittances to state authorities.

Wise offers business accounts with real U.S. banking details (routing and account numbers) that can be opened remotely without visiting a branch or forming a U.S. entity. It supports international transfers and dollar management.

Once you have your U.S. address, EIN, and bank account, you are ready to register for sales tax in the states where you have economic nexus.