Key takeaways
- 1You must have an EIN if you have employees, operate as a corporation or partnership (including a multi-member LLC), file employment, excise or alcohol, tobacco and firearms tax returns, or withhold tax on non-wage payments to a nonresident alien.
- 2A sole proprietor or single-member LLC with no employees and no excise taxes can use a Social Security number, but a free EIN keeps that number off W-9s and makes opening a business bank account easier.
- 3Applying online at IRS.gov is free and gives you the EIN at the end of the session. Fax takes about 4 business days and mail about 4 weeks.
- 4The IRS never charges for an EIN. Websites that charge a fee are filling in the same free form for you.
- 5Keep the CP 575 notice the IRS issues. If you lose it, call 800-829-4933 and ask for Letter 147C, which confirms your EIN.
In this guide
- What an EIN is
- Who must have an EIN
- Decision table: does your business need an EIN?
- Why a sole proprietor or single-member LLC may want one anyway
- How to apply for an EIN on IRS.gov
- Other ways to apply, and how long each takes
- Worked example: a new two-member LLC
- After you get it, and when you need a new one
- Frequently asked questions
What an EIN is
An employer identification number is a nine-digit number the IRS assigns to a business, written as 12-3456789. It does for a business what a Social Security number does for a person: it identifies the business on tax returns, payroll filings, information returns and bank paperwork.
The name is misleading. You do not need employees to get one, and many one-person businesses have one. Getting an EIN also does not change how your business is taxed. A single-member LLC with an EIN is still taxed like a sole proprietorship unless it elects otherwise.
Who must have an EIN
The IRS says you need an EIN if any of the following applies. The test is about what the business does and how it is set up, not how much it earns.
- You have employees, even one part-time worker.
- You operate as a corporation or a partnership. A multi-member LLC is taxed as a partnership by default, so it needs one.
- You file employment, excise, or alcohol, tobacco and firearms tax returns. A sole proprietor who files Form 720 for excise tax needs one even with no staff.
- You withhold tax on income, other than wages, paid to a nonresident alien.
- You set up a retirement plan that needs its own number, such as a Keogh plan. Trusts, estates, tax-exempt organizations and farmers’ cooperatives also need one.
Decision table: does your business need an EIN?
Find the row closest to your situation. “Optional” means federal tax rules let you use your SSN, but a bank, a state agency or a client may still ask for an EIN.
| Business set-up | EIN required? | Why |
|---|---|---|
| Sole proprietor, no employees, no excise tax | Optional | Income goes on Schedule C under your SSN |
| Sole proprietor who hires an employee | Yes | Needed for payroll tax deposits, Form 941 and W-2s |
| Single-member LLC, no employees, no excise tax | Optional | Disregarded for income tax, so your SSN can be used |
| Single-member LLC with employees | Yes | The LLC needs its own EIN for employment taxes |
| Multi-member LLC or partnership | Yes | Files its own Form 1065 return |
| Corporation, or LLC taxed as a C or S corporation | Yes | Files its own corporate return |
| Any business filing excise returns, such as Form 720 | Yes | Excise returns require an EIN |
Why a sole proprietor or single-member LLC may want one anyway
If federal rules do not require an EIN, it is still worth the ten minutes for most people who do client work. Every client who pays you $2,000 or more in 2026 should ask for a Form W-9 so it can send you a 1099-NEC. If you give an SSN, it sits in each client’s files and email inbox. A freelancer with a dozen clients hands out their SSN a dozen times a year. An EIN goes on those forms instead, so your SSN stays out of their files.
Banks are the other common reason. Most banks ask for an EIN to open a business account in the business’s name, and keeping business money separate from personal money makes bookkeeping and tax time much easier. Some state agencies ask for one too.
An EIN does not replace your SSN on your own return. You still report the income on Schedule C and pay self-employment tax on the profit.
Free toolSelf-employment tax calculatorHow to apply for an EIN on IRS.gov
The online application is free and gives you the number at the end of the session. You can use it if your principal place of business is in the United States or a U.S. territory. Before you start, form your LLC or corporation with your state if you are creating one. The IRS says applying first can delay the application.
The applicant must be the responsible party, meaning the person who ultimately owns or controls the business, or someone they have authorized. You need the responsible party’s SSN or ITIN. The IRS issues only one EIN per responsible party per day, whichever method you use.
The session cannot be saved and times out after 15 minutes of inactivity, so have the legal name, address, start date, entity type and expected number of employees ready. As of November 2026 the online system is open at these times (Eastern time):
- Monday to Friday: 6 a.m. to 1 a.m. the next day.
- Saturday: 6 a.m. to 9 p.m.
- Sunday: 6 p.m. to midnight.
- Hours and rules change, so check the IRS “Get an employer identification number” page before you apply.
Other ways to apply, and how long each takes
If you cannot use the online application, fill in Form SS-4 and fax or mail it. Include your fax number so the IRS can fax the EIN back. Phone applications are only for international applicants, meaning those with no principal place of business in the United States. The IRS no longer issues EINs by phone to domestic businesses.
| Method | Who can use it | Where | Time to receive the EIN |
|---|---|---|---|
| Online | Principal business in the U.S. or a U.S. territory | IRS.gov EIN online application | At the end of the session |
| Fax (Form SS-4) | Anyone | 855-641-6935 for U.S. applicants | Generally within 4 business days |
| Mail (Form SS-4) | Anyone | Internal Revenue Service, Attn: EIN Operation, Cincinnati, OH 45999 | About 4 weeks |
| Phone | International applicants only | 267-941-1099, Mon to Fri, 6 a.m. to 11 p.m. Eastern (not toll-free) | During the call |
Worked example: a new two-member LLC
Two partners form a cleaning business as an LLC. The state approves the LLC on Monday, November 9, 2026, and they plan to hire their first employee before December. Because the LLC has two members, it must have an EIN. Here is how the method they choose changes the timeline.
- Online, they can open the business bank account the same day and set up payroll in good time for a December hire.
- The IRS says a new EIN can be used straight away for a bank account, business licenses or a paper return, but it can take up to 2 weeks before it works for e-filing, electronic payments and TIN matching.
- By mail, the number would arrive about when their first payroll is due. Applying online avoids that squeeze.
| Method | EIN received | Can open a bank account | Can e-file and make electronic tax deposits |
|---|---|---|---|
| Online | Mon, Nov 9 | Mon, Nov 9 | Up to 2 weeks later, by about Mon, Nov 23 |
| Fax | About Mon, Nov 16 (4 business days; Nov 11 is a federal holiday) | About Mon, Nov 16 | Up to 2 weeks after the EIN is issued |
| About Mon, Dec 7 (about 4 weeks) | About Mon, Dec 7 | Up to 2 weeks after the EIN is issued |
After you get it, and when you need a new one
At the end of an online application the IRS gives you a confirmation notice, the CP 575. Save it as a PDF and print a copy. Banks and some agencies ask to see it, and the IRS will not send a duplicate. If you lose it, check old tax returns, your bank or your state license records first. Then call the Business and Specialty Tax Line on 800-829-4933, Monday to Friday, 7 a.m. to 7 p.m. local time, and ask for Letter 147C, “EIN Previously Assigned”, which confirms the number. Eligible users can also download a digital CP 575 from an IRS Business Tax Account.
Put the EIN on your W-9s, invoices where clients ask for it, payroll filings and business tax returns. You generally need a new EIN only when ownership or structure changes, not for a new name or address.
- New EIN needed: a sole proprietor incorporates or takes on a partner; a partnership incorporates or ends and a new one starts; an LLC is ended to form a new corporation or partnership; a corporation gets a new state charter or becomes a subsidiary.
- No new EIN: changing the business name or location, a corporation electing S corporation status, an LLC changing its tax election, or a sole proprietor running several businesses.
