What Is an EIN Number? How to Get One Free, Step by Step

Quick honest confession before this guide even starts: “EIN number” is technically redundant, the same way “PIN number” and “ATM machine” are — the N in EIN already stands for Number. Everyone says it anyway, including most of the IRS’s own plain-language materials, so this guide won’t fight that battle. What actually matters is what the thing does, not what to call it.

Here’s the cleanest way to think about it: a person has a Social Security number. A business has an EIN. Both exist so a government agency has one consistent way to identify you across every form, filing, and account you’ll ever touch — and just like an SSN, an EIN follows the business it’s assigned to for its entire life, showing up on tax returns, bank applications, payroll filings, and licenses long after the paperwork that created it is forgotten.

This guide covers exactly what an EIN is, a quick self-check for whether you actually need one, who qualifies as the all-important “responsible party,” the real step-by-step application process (for free, directly through the IRS), how an EIN differs from an SSN, ITIN, and DUNS number, and what to do if you’ve lost track of one you already have.

(A quick note: this article explains how EINs generally work. It isn’t formal legal or tax advice — specific situations, especially around entity changes or foreign ownership, are worth confirming with a CPA or directly at IRS.gov.)

What Is an EIN?

An Employer Identification Number (EIN) — also called a Federal Tax ID or FEIN — is a unique nine-digit number issued by the IRS to identify a business entity, formatted as XX-XXXXXXX. It functions as a business’s equivalent of a Social Security number: used to file tax returns, open bank accounts, apply for licenses, hire employees, and generally exist as a recognizable entity in the eyes of the IRS, banks, and state agencies.

Despite the name, you don’t need actual employees to need or qualify for an EIN — plenty of one-person businesses with zero employees get one anyway, for reasons covered in the self-check below.

Do You Actually Need an EIN? A Quick Self-Check

Answer yes to any of these, and an EIN isn’t optional:

• Do you have, or plan to hire, employees? An EIN is required the moment you plan to run payroll — it’s the identifier every layer of payroll tax ultimately reports back to.
• Is your business a partnership, corporation, or multi-member LLC? Any of these structures requires an EIN regardless of whether you have employees, since the entity itself needs to be able to file its own tax return separate from any individual owner’s return. Our guides to what an LLC is and what an S corporation is both cover this requirement as part of formation.
• Are you filing excise, alcohol, tobacco, or firearms tax returns? These specialized federal tax categories require an EIN regardless of business size or structure.
• Do you administer a trust, estate, or nonprofit organization? These generally need their own EIN, separate from any individual’s SSN.
• Do you want to open a business bank account? Most banks require an EIN to open an account in the business’s name, even for a sole proprietorship that isn’t legally required to have one.

If none of these apply — you’re a single-member LLC or sole proprietorship with no employees — an EIN is technically optional; the IRS allows you to use your personal Social Security number instead. In practice, most business owners get one anyway, for reasons that have nothing to do with legal requirement: it keeps your SSN off client-facing paperwork like a W-9 form, it’s usually required to open a dedicated business bank account (itself essential for maintaining any LLC’s liability protection), and it simply reads as more established to clients, vendors, and lenders. It’s also completely free, so there’s rarely a real downside to getting one even when it isn’t strictly mandatory.

EIN Requirements by Business Structure

The self-check above covers the general rule, but it’s worth seeing how it plays out across the specific structures most small businesses choose between:

• Sole proprietorships are the one structure where an EIN is genuinely optional with no employees — the business and owner are the same legal taxpayer, so the owner’s SSN works as a substitute. The moment a sole proprietor hires even one employee, that optionality disappears.
• Single-member LLCs follow the sole proprietorship’s default tax treatment (a “disregarded entity”), so the same optionality technically applies — but in practice, nearly every bank requires an EIN to open an account in the LLC’s name, which makes it a practical necessity even when it isn’t a strict legal one.
• Multi-member LLCs require an EIN in every case, since the LLC files its own partnership-style informational return separate from any individual member’s personal return.
• Corporations — C corps and S corps alike — always require an EIN, since a corporation is legally required to be a separate taxpayer from its owners the moment it’s formed. Our guides to what an incorporator is and what corporate bylaws are cover the broader formation paperwork an EIN application fits alongside.
• Nonprofits need an EIN before they can even apply for federal tax-exempt status — it’s one of the first steps in the formation sequence, not something requested afterward.

Protecting Your EIN From Misuse

An EIN isn’t quite as sensitive as a Social Security number — it appears on plenty of semi-public documents, including some government filings — but it’s still a piece of information worth treating with reasonable care rather than handing out casually. A stolen EIN can be used to attempt fraudulent tax filings, apply for credit in a business’s name, or file fake documents with a state agency. A few practical habits: only provide it to parties who have a legitimate reason to request it (banks, the IRS, a client requesting a W-9), store the original confirmation notice securely rather than in a shared or public location, and monitor for unexpected IRS notices referencing activity you didn’t initiate, which can be an early sign of misuse.

Who Can Be the “Responsible Party”?

This is the part of the EIN application most guides skim past, and it’s worth understanding before you apply, not during. Every EIN application requires naming a responsible party — the individual who ultimately owns, controls, or exercises effective control over the entity and the disposition of its funds and assets. A few rules that trip people up:

• It has to be an individual person, not another business entity, except in specific government-entity cases. You can’t list your holding company as the responsible party — you need an actual human being with a Social Security number or Individual Taxpayer Identification Number (ITIN).
• It doesn’t have to be the majority owner — it has to be whoever genuinely controls the entity’s funds and major decisions, which is sometimes a managing member or officer rather than the largest shareholder.
• There’s a strict limit: one EIN per responsible party per calendar day. If you’re forming multiple entities at once, you’ll need to spread the applications across different days — or, if genuinely necessary, use a different eligible responsible party for each.
• The responsible party’s information can change over time, and when it does, the IRS expects to be told — covered in the “does an EIN expire” section below.

How to Get an EIN: Step-by-Step

Here’s the actual process, in order:

1. Confirm your business is legally formed (if applicable). If you’re forming an LLC or corporation, most states expect that formation to be complete, or at least in progress, before an EIN application — the EIN identifies an entity that needs to actually exist.
2. Gather your information before you start. You’ll need the legal name and any trade name (DBA) of the business, the mailing and physical address, the entity type, the reason you’re applying, and the responsible party’s full legal name and SSN or ITIN.
3. Apply directly at IRS.gov — never through a third-party site that charges a fee. This is worth repeating clearly: getting an EIN is completely free directly from the IRS. A wide range of third-party “EIN filing service” websites charge anywhere from $50 to $300+ to submit the exact same free application on your behalf — sometimes clearly disclosed as a service fee, sometimes designed to look like an official government charge. Neither is illegal, but neither is necessary either; the online application takes most applicants well under thirty minutes.
4. Complete the online session in one sitting. The IRS online EIN application is available Monday–Friday 6 a.m.–1 a.m. ET, Saturday 6 a.m.–9 p.m. ET, and Sunday 6 p.m.–midnight ET, and it expires after 15 minutes of inactivity — meaning you can’t save a partially completed application and return to it later. Having your information gathered ahead of time (step 2) avoids losing progress mid-application.
5. Receive your EIN immediately upon completion. Unlike almost every other IRS interaction, the online application issues your EIN instantly at the end of the session, along with a downloadable confirmation notice (an EIN assignment letter) — save this PDF immediately, since it’s the cleanest proof of your EIN for opening a bank account or completing other paperwork in the following days.
6. If you’re not eligible for the online application — most commonly because your business’s principal location is outside the U.S. — you can apply by phone, fax, or mail instead, using Form SS-4. These methods take longer (fax typically around four business days; mail can take four weeks or more) but reach the same result.

EIN vs. SSN vs. ITIN vs. DUNS Number: What’s the Difference?

These four numbers get confused constantly, mostly because they’re all nine digits and all function as some kind of identifier — but they’re issued by different organizations, for different purposes, to different kinds of applicants:

NerdWallet’s comparison of EIN, ITIN, and SSN is a solid independent second opinion if you want to see this same breakdown from another angle. The DUNS number comparison is worth calling out specifically, since it’s the one most business owners eventually run into and find genuinely confusing: it looks and functions like a tax ID, but it isn’t one at all — it’s a private identifier from Dun & Bradstreet used for business credit reports and required for federal government contracting, entirely separate from anything the IRS issues. Our guide to what a DUNS number is covers that distinction in full if you’re weighing whether your business needs one alongside its EIN.

What to Do With Your EIN Once You Have It

Getting the number is the easy part — here’s where it actually gets used:

• Open a dedicated business bank account. Nearly every bank requires an EIN (or, for a sole proprietor choosing not to get one, an SSN) to open an account in the business’s name, and keeping business funds separate from personal funds is essential to maintaining any LLC’s liability protection.
• Register for state and federal payroll tax accounts the moment you plan to hire — every layer of payroll tax, from FICA withholding to state unemployment tax, is tracked against your EIN.
• Apply for business licenses and permits, many of which require an EIN as part of the application.
• Build a business credit profile. An EIN allows a business to establish credit history separate from the owner’s personal credit, which matters increasingly once the business seeks its own financing — including a business line of credit or loan.
• File your business tax return, whichever form applies to your entity type — and provide it on any W-9 form a client requests before paying you.

Lost or Forgot Your EIN? How to Look It Up

This happens more often than you’d think, especially for a business that got its EIN years ago and hasn’t needed it since. A few places to check, roughly in order of how fast they’ll get you an answer:

1. Check your EIN confirmation notice (CP 575). This is the letter the IRS issued when the EIN was first assigned — if you kept it (physically or as a saved PDF from an online application), it’s the fastest source.
2. Check a prior year’s business tax return. Your EIN appears on every return you’ve filed.
3. Check with your bank. Any business bank account was opened using your EIN, and most banks can look up the number associated with an account on file.
4. Check other business paperwork — loan applications, state licenses, and payroll records typically all reference the EIN.
5. Call the IRS Business & Specialty Tax Line directly if none of the above work. The IRS can verify your EIN over the phone, but only to someone who can verify their authority to receive it — generally the responsible party or another authorized person on file for the business.

Does an EIN Expire or Need Renewal?

No — once assigned, an EIN is permanent and never expires, even if the business becomes inactive for a period. It also doesn’t need to be renewed. What can change is the responsible party on file, and the IRS expects to be notified of that specific change within 60 days, using Form 8822-B. This is easy to overlook, especially after an ownership change or a change in who manages the business day to day, but keeping it current matters — the responsible party is who the IRS contacts for certain notices and who has authority to make changes to the EIN record later.

Common EIN Mistakes

• Paying a third-party website for something that’s free. Worth saying one more time given how common it is: getting an EIN directly from the IRS costs nothing, and the application itself typically takes under thirty minutes.
• Assuming an EIN is the same as registering your business. It isn’t. An EIN identifies your business for federal tax purposes; it doesn’t create your LLC or corporation (that’s a separate state filing), and it doesn’t register your business name, trademark, or a “doing business as” (DBA) with your state or county — those are all separate steps covered in our guide to how to choose a company name.
• Applying for a new EIN when you didn’t need one. Certain changes — like moving your business to a new location, or a sole proprietor simply changing their business name — generally don’t require a brand-new EIN. Getting a genuinely new one when your existing one still applies creates confusing, duplicate records.
• Losing track of the confirmation notice. It’s the single easiest document to misplace since it’s typically only needed once, right after formation — saving a digital copy immediately avoids a future scramble.
• Not updating the responsible party after an ownership or management change, leaving outdated contact information on file with the IRS for an entity that may need it later.
• Trying to rush the online application without gathering information first, then losing the entire session to the 15-minute inactivity timeout and having to start over.

Frequently Asked Questions

What is an EIN number used for? An EIN identifies a business for federal tax purposes and is used to file business tax returns, run payroll, open a business bank account, apply for licenses, and build business credit.

Is getting an EIN really free? Yes. The IRS issues EINs at no cost directly through IRS.gov. Third-party sites that charge a fee are providing a paid convenience service for something the IRS itself provides free.

Do I need an EIN if I’m a sole proprietor with no employees? Not legally required — you can use your Social Security number instead — but most sole proprietors get one anyway to keep their SSN off client paperwork and to open a dedicated business bank account.

How long does it take to get an EIN? Instantly, if you apply online and are eligible (a domestic entity with a U.S. principal place of business). Fax applications typically take about four business days; mail applications can take four weeks or more.

What is a responsible party on an EIN application? The individual who ultimately owns, controls, or manages the entity and its funds — it must be an actual person with an SSN or ITIN, not another business entity, and is limited to one EIN application per calendar day.

Can I have more than one EIN for the same business? Generally no, and you shouldn’t apply for a new one if your existing EIN still applies to the same entity — certain structural changes (converting to a different entity type, for example) may require a new one, but a name change or address change usually doesn’t.

What’s the difference between an EIN and a DUNS number? An EIN is a government-issued federal tax ID from the IRS. A DUNS number is a private identifier issued by Dun & Bradstreet, used for business credit profiles and federal contracting — not a tax ID at all.

Does an EIN expire? No. Once issued, an EIN is permanent, even during periods when the business is inactive. What can change is the responsible party on file, which should be updated using Form 8822-B when it does.

What if I lost my EIN? Check your original confirmation notice, a prior tax return, or your business bank records first — all reference your EIN. If none are available, the IRS Business & Specialty Tax Line can verify it by phone for an authorized person on file.

Can a non-U.S. citizen get an EIN? Yes. Citizenship isn’t a requirement — the responsible party needs an SSN or ITIN, and a foreign national without either can still apply by phone, fax, or mail, though not through the online application, which is limited to entities with a U.S. principal place of business.

Is an EIN the same as a business license? No, and this is one of the most common mix-ups. An EIN is a federal tax identifier from the IRS; a business license is a separate state or local authorization to legally operate, applied for separately and often required in addition to, not instead of, an EIN.

Final Thoughts

An EIN is one of the least complicated pieces of paperwork in starting a business — a free, usually instant application that, once complete, quietly sits in the background of nearly everything else the business ever files, banks, or hires. The parts worth taking seriously are the ones that are easy to rush past: confirming who the responsible party actually should be, applying directly at IRS.gov instead of paying a third party for a free service, and saving the confirmation notice somewhere you’ll actually find it again.

From there, the EIN becomes the quiet thread running through everything downstream — the bank account, the payroll tax accounts, the W-9 forms you’ll fill out for clients, and the business credit profile you’ll eventually want to build. Getting it right at the start, in fifteen minutes, is considerably easier than untangling it later.