What Is an EIN (Employer Identification Number)? Definition and Use

Definition

EIN (Employer Identification Number) - An EIN (Employer Identification Number) is the nine-digit federal tax ID the IRS assigns to a business, used for banking, hiring, tax filing, and payments.

Every US LLC needs an EIN to open a business bank account, apply for a payment processor like Stripe, or hire employees, and even a single-member LLC taxed as a disregarded entity must obtain one for banking. The number is requested on Form SS-4, which names a responsible party, a natural person the IRS keeps on file but never publishes. That private linkage is why an EIN does not undo state-record anonymity.

The most persistent myth is that non-residents cannot get an EIN because they lack a Social Security Number. They can. The SS-4 lets a foreign responsible party write 'Foreign' in place of an SSN or ITIN, and the application is submitted by fax to the IRS with a third-party designee. Online issuance is instant for SSN holders; the fax route for non-residents typically takes several business days and returns the same nine-digit number plus a CP 575 confirmation letter.

For an anonymous LLC across Wyoming, New Mexico, Delaware, or Nevada, the EIN is where private identity attaches at the federal level while the state record stays blank. The responsible party is usually the beneficial owner or managing member, identified to the IRS but not to any public registry. Anonymousllc.co includes EIN acquisition in every formation package and offers it standalone at $99 for existing LLCs.

A common practical mistake is a name mismatch between the SS-4 and the state filing, or an incomplete responsible-party field, either of which causes the IRS to reject or delay the EIN. Losing the CP 575 is another frequent headache, since the IRS issues it only once and a replacement 147C verification letter can take weeks to arrive, exactly when a bank or processor is waiting on it to open the account. Keeping the original CP 575 safe from day one prevents that delay entirely.