✓ Basics

What is an EIN?

A plain-English explanation of Employer Identification Numbers, who needs one, and what they are not.

By Reba Donaldson · Last reviewed: April 2026

An EIN is just an ID number for a business

An Employer Identification Number, or EIN, is a nine-digit number the IRS issues to identify a business or other entity. It is also called a Federal Tax ID Number or Federal Employer Identification Number (FEIN). Same thing, three names.

The format looks like this:

12-3456789

The dash is part of the format. When you see an EIN written out, that is how it should look.

What "Employer" Identification Number is misleading about

The name suggests you only need one if you have employees. That is wrong. The EIN is just an ID, and lots of businesses without employees have one. Sole proprietors, single-member LLCs, freelancers, real estate investors, owners of trusts and estates. None of them have employees in the traditional sense, and many of them have EINs.

The IRS picked the name decades ago when EINs were primarily issued to employers for payroll tax purposes. The use cases expanded. The name did not.

What an EIN is NOT

Three things people commonly think the EIN does that it does not:

An EIN is not a business license. Local and state licenses are separate.
An EIN does not register your business name. That happens at the state level when you file your LLC or DBA.
An EIN does not make you tax-exempt. Nonprofits need an EIN AND a separate determination from the IRS.

What an EIN actually does for you

The EIN does four useful things:

Practical uses

Tax filings

Required on partnership returns, corporate returns, payroll tax returns, and estate returns. Sole proprietors can use SSN or EIN.

Bank accounts

Banks use the EIN to verify and open business accounts.

W-9s and 1099s

You give the EIN to clients on a W-9 instead of your SSN. Your privacy stays intact.

Hiring

Required for any W-2 employer. The EIN is what links you to your payroll tax account.

How EINs differ from SSNs and ITINs

Three nine-digit IRS identifiers exist, and they get confused all the time:

Identifier types

SSN

Issued by the Social Security Administration to individuals. Format: 123-45-6789. Used for personal tax returns.

EIN

Issued by the IRS to businesses and entities. Format: 12-3456789. Used for business tax filings.

ITIN

Issued by the IRS to individuals who cannot get an SSN (typically non-US tax filers). Format: 9XX-XX-XXXX. Used for personal tax returns by non-citizens.

Full breakdown on the EIN vs SSN and EIN vs ITIN pages.

Will my EIN ever change?

For most businesses, no. Once issued, an EIN sticks with the entity forever. The IRS does not recycle EINs.

However, certain events can require a NEW EIN:

You change from sole proprietor to corporation or partnership
You change from partnership to corporation
You incorporate an existing sole proprietorship
You buy or inherit an existing business (you usually need a new EIN)
The business goes through bankruptcy

Most simple changes (adding members to an LLC, changing your address, renaming the entity) do NOT require a new EIN. The IRS publishes a list of cases if you want to check yours.

Where do I find my EIN later?

After you apply, the IRS issues a confirmation letter (Notice CP 575). Save the PDF. Print it. Keep it where you keep your formation documents.

If you lose it, you can find your EIN on:

Past tax returns for the business
Bank account opening paperwork
Old 1099s issued to your business
By calling the IRS Business and Specialty Tax Line at 800-829-4933

Full recovery options on the lost EIN page.