LLCFormation.ioWhat Is an EIN?
An EIN — Employer Identification Number — is the federal tax ID the IRS assigns to your business. You'll need one to open a business bank account, hire employees, and file business taxes. The good news: getting an EIN from the IRS is free and usually takes minutes. This guide explains what an EIN is, when you need one, and how to get it.
EIN Basics: Your Business's Federal Tax ID
An Employer Identification Number (EIN) is a unique nine-digit number the IRS assigns to a business entity for tax administration. It's formatted like 12-3456789.
Despite the name, you don't need employees to need one. The EIN functions as your business's federal identity — it's how the IRS, banks, and government agencies identify your company, the way a Social Security number identifies an individual.
Key facts:
- Issued by the IRS (federal), not by your state
- Free — there is never a government fee for an EIN
- Each business entity gets its own EIN; it's tied to the entity, not to you personally
- It doesn't expire, and you generally keep the same EIN for the life of the business. The application itself takes only a few minutes, and the IRS issues the number directly with no intermediary required.
When Does Your LLC Need an EIN?
You'll need an EIN if your LLC:
- Has employees (or will hire them)
- Is a multi-member LLC (the IRS requires one for partnership-taxed entities)
- Elects to be taxed as a corporation (S corp or C corp)
- Needs a business bank account — virtually all banks require an EIN to open a business account
- Files certain tax returns or excise taxes
What about a single-member LLC with no employees? Technically, the IRS doesn't require an EIN — you can use your Social Security number. But in practice, most single-member LLC owners get one anyway because:
- Banks require it for a business account
- It keeps your SSN off vendor forms and client paperwork (better privacy)
- You'll need it the moment you hire your first employee or elect corporate taxation
Bottom line: even when it's not strictly required, getting an EIN is free, fast, and useful. Most LLC owners should just get one.
How to Get an EIN (Free From the IRS)
There are three ways to apply, all through the IRS:
- Online (fastest): The IRS online EIN application is available to applicants with a valid Taxpayer Identification Number (SSN or ITIN). If you qualify, you receive your EIN immediately upon completing the application. Note the online system has limited hours of operation.
- By fax: Submit Form SS-4 by fax; processing takes about 4 business days.
- By mail: Submit Form SS-4 by mail; allow 4–5 weeks.
For applicants without an SSN or ITIN (such as non-US residents), the online application isn't available — you'll apply by fax or mail, or have someone apply on your behalf. See our guide for non-US residents forming an LLC for details.
Important: Apply only through the official IRS website (irs.gov). Third-party sites that charge for "EIN filing" are selling you a free service — the number itself never costs anything.
EIN Mistakes to Avoid
A few things founders often get wrong:
- An EIN is not a state tax ID. Some states issue their own tax IDs for sales tax or employer withholding — those are separate from your federal EIN.
- An EIN doesn't replace business licenses. It's a tax identifier, not permission to operate.
- You don't need a new EIN if you move states. The EIN stays with the entity.
- You generally don't need a new EIN when you change your LLC's name or address — you just notify the IRS.
- Each separate LLC needs its own EIN. If you own three LLCs, that's three EINs.
- Never share your EIN carelessly. Like an SSN, it can be misused for fraud — share it only with banks, tax authorities, and trusted parties.
EIN vs Other Tax IDs: What's the Difference?
Founders often juggle several tax identifiers. Here's how the EIN fits among them:
- EIN (federal, business): Issued by the IRS. Identifies your business for federal tax purposes. Free, nine digits, format 12-3456789.
- SSN (federal, personal): Your personal Social Security number. Never use it where an EIN belongs — every time you hand your SSN to a vendor or client, you expose yourself to identity theft.
- ITIN (federal, personal): For individuals who need a US tax ID but can't get an SSN — common for non-US resident founders. Used on the EIN application when there's no SSN.
- State tax IDs: Many states issue their own numbers for sales tax, employer withholding, or state income tax. These are separate from your EIN — getting a federal EIN doesn't register you for state taxes.
- State entity numbers: Some states assign a registration number when your LLC is approved. That's a corporate registry number, not a tax ID.
When to use which: Use your EIN on business tax returns, when opening business bank accounts, on W-9s you provide to clients, and for hiring. Use state tax IDs for state filings. Keep your SSN for personal matters only.
One more distinction worth knowing: the IRS issues only one EIN per entity. If someone tells you that you need to 'renew' your EIN annually or pay for an 'EIN certificate,' that's a scam — EINs don't expire and never require renewal.
What to Do After You Get Your EIN
Once you have your EIN:
- Open a business bank account — this is the single most important step for keeping your liability protection intact.
- Use it on tax filings instead of your personal SSN where business identification is required.
- Provide it to payers who need it for information returns (like 1099s).
- Keep your confirmation letter (CP 575) in your business records — banks and agencies sometimes ask to see it.
If you lose the letter, you can request a replacement confirmation (Letter 147C) from the IRS.
This is general information about a standard IRS process, not tax advice. For questions about how your EIN relates to your tax obligations, consult a tax professional.
Forming your LLC and need help with the EIN step too? llcformation.io/ provides private formation assistance in all 50 states, including EIN application guidance. Message us on WhatsApp at +92 314 9150035.
Frequently asked questions
What does EIN stand for?
EIN stands for Employer Identification Number. It's a nine-digit federal tax ID issued by the IRS, formatted like 12-3456789. Think of it as a Social Security number for your business.
Is an EIN free?
Yes — applying for an EIN directly through the IRS is completely free. You should never pay a government fee for one. Some services charge for handling the application for you, but the number itself costs nothing.
How long does it take to get an EIN?
If you apply online and qualify, you typically receive your EIN immediately at the end of the application. Fax applications take about 4 business days; mailed applications can take 4–5 weeks.
What if I lose my EIN?
If you lose your EIN confirmation letter, you can call the IRS Business & Specialty Tax Line to retrieve it, or check old tax returns and bank documents where it appears.
Related guides
Ready to start your LLC?
Tell us about your business and we'll guide you through formation — in your state, step by step.