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DefinitionAn EIN, or Employer Identification Number, is a 9-digit federal tax ID that the IRS assigns to a US business. It is the business equivalent of a Social Security Number, and almost
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What Is An Ein · File.Business

What is an EIN? The federal tax ID, explained.

An EIN, or Employer Identification Number, is a 9-digit federal tax ID that the IRS assigns to a US business. It is the business equivalent of a Social Security Number, and almost every US LLC, Corporation, partnership, or other entity needs one to open a bank account, hire employees, file taxes, or apply for licenses.

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Formal Definition

An Employer Identification Number (EIN), also called a Federal Employer Identification Number (FEIN) or Federal Tax Identification Number, is a unique 9-digit number assigned by the Internal Revenue Service (IRS) to identify a business entity for federal tax purposes.

In plain English

Here is what that actually means.

Think of an EIN as the Social Security Number for a business. Just as the IRS uses your SSN to identify you on your personal tax return, it uses your EIN to identify your LLC, Corporation, or other entity on the business return. Banks use it to verify the entity when you open a business account. Payroll providers use it to file the entity's payroll tax returns. The state may also reference it when you register for state employer taxes.

The EIN format is two digits, a hyphen, then seven digits: XX-XXXXXXX. The first two digits used to indicate which IRS service center issued the number, but that meaning has largely been retired with the move to online issuance. There is no fee to obtain an EIN; the IRS issues them for free directly through irs.gov.

Once issued, an EIN is permanent for the life of the entity. You do not renew it. If the entity is sold or restructured significantly, a new EIN may be required. If the entity dissolves, the EIN is not "released" or re-used; it stays associated with that entity in IRS records.

Key facts

The four things to know.

9-digit number
Format: XX-XXXXXXX, assigned by the IRS
Free from the IRS
No fee to obtain. We file the application for you.
Permanent
Issued once, lasts the life of the entity, does not renew
Required for most
Any LLC, Corp, employer, or business bank account needs one
Ready to take the next step?Pay only the state fee. 5 minutes to start.
Who needs this

Common situations.

LLCs and Corporations Required to open business banking, hire employees, file federal taxes.
Sole proprietors with employees Required as soon as you hire any W-2 employee.
Trusts and estates Required to file Form 1041 for income.
Nonprofit organizations Required before filing for 501(c)(3) tax exemption.
Partnerships Required to file Form 1065 partnership return.
Real estate holding LLCs Required to open the rental property bank account.
How it compares

Related concepts side by side.

EIN vs SSN
SSN is for individuals. EIN is for business entities. Some single-member LLCs use the owner's SSN, but every bank prefers an EIN.
EIN vs ITIN
ITIN (Individual Taxpayer Identification Number) is for non-US individuals who need to file US taxes. EIN is for businesses.
EIN vs State Tax ID
EIN is federal. Most states also issue a separate state-level employer ID for state payroll tax filings.
EIN vs Business License Number
A business license number is issued by a city or state and licenses you to operate. The EIN is your federal tax ID.
FAQ

Common questions.

How much does it cost to get an EIN?
Free from the IRS. We file Form SS-4 for you at no charge with every formation.
How fast can I get an EIN?
For US founders with a valid Social Security Number, same business day via online application. For non-US founders without an SSN, 1 to 3 weeks via paper SS-4 submitted by fax.
Can I get an EIN before forming the LLC?
No. The IRS requires the LLC or Corp to be formed first (Articles filed with the state). The EIN application references the entity name and formation date.
Do single-member LLCs need an EIN?
Technically you can use your SSN, but every business bank, payment processor, and customer-W-9 vendor will ask for an EIN. We strongly recommend it.
Can a non-US person get a US EIN?
Yes. The IRS issues EINs to entities owned by non-US persons. The application uses a passport or other ID instead of an SSN. We file by paper SS-4 (faster via fax than mail).
How do I look up my EIN?
Check your IRS confirmation letter (CP 575). If you have lost it, request a 147-C verification letter from the IRS by phone or written request. We help customers retrieve this.
Does the EIN change if I move states?
No. The EIN is permanent and federal. Moving states does not change it. You will need to register for state-level employer tax IDs in the new state.
Can multiple LLCs share one EIN?
No. Each separately-formed entity needs its own EIN. Holding company structures with multiple LLC subsidiaries each have their own EIN.
When does an EIN expire?
Never. It is issued for the life of the entity. If the entity dissolves, the EIN is not transferable to a different entity.
What if I never use my EIN?
No penalty. EINs can be obtained and never used; the IRS does not require activity. Worth obtaining if you plan to operate within the next year or two.
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