Written & reviewed by NotALawyer Review AI · Updated June 26, 2026
An EIN — Employer Identification Number — is a free federal tax ID for your business, kind of like a Social Security number for the company. You get it directly from the IRS, usually online in a few minutes, and it's free: the IRS never charges, so steer clear of look-alike sites that want a fee to 'help' you apply. You'll use your EIN to file business taxes, run payroll, and open a business bank account.
An EIN identifies your business to the IRS the way an SSN identifies you. You'll need it to file federal business taxes, hire and pay employees, open a business bank account, and apply for many business licenses or loans.
Under federal rules, you generally need an EIN if your business has employees, operates as a corporation or partnership, or files certain tax returns. Many single-member LLCs and sole proprietors aren't strictly required to have one, but get an EIN anyway so they can keep their SSN off forms and open a business bank account.
The fastest route is the IRS's free online EIN application, which issues the number immediately once you finish. You can also apply by mail or fax with Form SS-4. Either way the IRS charges nothing — if a website asks for a payment, you're not on the official site.
Search results often surface third-party services that charge to file the free form for you. They're not the IRS and aren't required. Going directly to the IRS keeps it free and gets you the number on the spot.
Say you've just formed a single-member LLC for freelance work. You're not required to have an EIN, but getting one — free, in minutes — lets you open a business checking account and hand clients a W-9 with your EIN instead of your Social Security number.
More on this topic: the Small Business hub
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