An EIN is written as two digits, a hyphen and seven digits, for example 12-3456789. The IRS calls it "a federal tax ID number for businesses, tax-exempt organizations and other entities" on its Employer ID Numbers page. You may also see it called a federal tax ID, a federal employer ID or FEIN, or a taxpayer identification number (TIN), which is the wider term that covers both EINs and SSNs.
What is an EIN used for?
- Federal tax returns and payroll. The business's returns, employment tax forms and W-2s carry it.
- Banking. Banks ask for it to open a business account. The IRS notes you can request an EIN for banking or state tax purposes even when federal tax law does not require one.
- Getting paid. Clients ask for it on Form W-9 so they can report what they pay you.
- State accounts and licenses. State tax registrations and many business licenses ask for it.
Who needs an EIN?
The IRS says you need an EIN if you:
- have employees;
- pay employment, excise, or alcohol, tobacco and firearms taxes;
- withhold tax on income, other than wages, paid to a nonresident alien;
- operate a partnership, corporation, LLC, tax-exempt organization, estate, most trusts, a retirement plan or a farmers' cooperative.
A single-member LLC is a special case. The IRS says one with no employees and no excise tax to report uses its owner's name and taxpayer ID for federal income tax, and needs its own EIN once it has employees or excise taxes (see the IRS page on single-member LLCs). In practice most LLCs get one anyway, because banks and state agencies ask for it.
EIN vs SSN: what is the difference?
| EIN | SSN | |
|---|---|---|
| Issued by | The IRS | The Social Security Administration |
| Issued to | Businesses, sole proprietors, nonprofits, estates, trusts | Individual people |
| Format | 00-0000000 | 000-00-0000 |
| Used for | Business tax returns, payroll, business bank accounts | Personal tax returns, wages, Social Security benefits |
| Cost | Free from the IRS | Free from the SSA |
Both are taxpayer identification numbers, and the IRS uses whichever one belongs on a return (IRS Publication 583 sets out both formats). A sole proprietor with no employees often works under their SSN. Many get a free EIN anyway, so they can give clients an EIN on a W-9 instead of their Social Security number. Once you have an EIN for the business, use it where the business's number is asked for: Publication 583 says not to use your SSN in place of an EIN on returns that call for one.
Is an EIN public?
No. The IRS does not publish EINs, and state business records do not include them. They do appear on some public documents, such as SEC filings of public companies and the returns of tax-exempt organizations. Our EIN lookup guide covers the legitimate ways to find one.
How do you get an EIN?
Apply with the IRS. Online, the number is issued at the end of the session; by fax it takes about four business days and by mail about four weeks. It costs nothing: the IRS says "You never have to pay a fee for an EIN." The step-by-step is in how to get an EIN.
Does an EIN change or expire?
It does not expire. The IRS says you generally need a new EIN when the entity's ownership or structure changes (for example a sole proprietorship that incorporates), but not to change the business's name, address or responsible party. If you close the business, the IRS cannot cancel the EIN, but it can deactivate it and close the business account; see how to dissolve an LLC.
Lost your EIN?
Look at the confirmation notice the IRS sent when it assigned the number, a past federal return, or ask your bank or the agencies that issued your licenses. If none of those work, the IRS will give it over the phone to an authorized person after verifying their identity: the number and steps are under "Lost or forgot EIN" on the IRS EIN page.
General information, not legal or tax advice. Facts checked 2026-10-26 against the official sources linked above; confirm with the state or the IRS before you file. How we check our facts · Report an error