What a Tax ID Is and Who Needs One
A Tax ID (also called an Employer Identification Number or EIN) is a nine-digit number the IRS assigns to identify your business, nonprofit, or other entity for tax purposes. You need one if you operate a business as anything other than a sole proprietor using your Social Security number, run a partnership, operate an LLC or corporation, or manage a nonprofit organization.
If you are a sole proprietor with no employees and no separate business structure, you can use your Social Security number instead. But most business structures — even single-owner LLCs — require a separate Tax ID. The IRS does not charge for one, and you do not need to have filed taxes yet to obtain it.
Key Takeaways
- You can obtain a Tax ID for free directly from the IRS by phone, mail, or online through their website.
- The online application (Form SS-4) takes about 15 minutes and gives you your number immediately if you apply during business hours.
- By phone, you call the IRS Business and Specialty Tax Line and receive your number the same day, but you must call during specific hours.
- By mail, you send Form SS-4 to the IRS address for your region and wait two to four weeks for a response.
- You will need your Social Security number, business address, and a description of what your business does.
Applying Online Through the IRS Website
The fastest way to obtain a Tax ID is through the IRS website at irs.gov. Go to the "Apply for an EIN" page and complete Form SS-4 online. The form asks for your name, Social Security number, business address, business structure type (sole proprietor, partnership, LLC, corporation, nonprofit, etc.), and a brief description of what your business does.
If you apply online during business hours (Monday through Friday, 7 a.m. to 10 p.m. Eastern time), the IRS will issue your Tax ID immediately on screen. You can print or save the confirmation page, which contains your new number. If you apply outside business hours, the system will assign your number and email it to you within one business day.
You do not need to have a business license, bank account, or employees yet. The IRS only needs to know that you intend to operate a business or organization. Keep your confirmation page in a safe place — you will need the Tax ID to open a business bank account, hire employees, and file taxes.
Applying by Phone
You can call the IRS Business and Specialty Tax Line at 1-800-829-4933 to obtain a Tax ID over the phone. Have your Social Security number, business address, and business description ready before you call. The representative will ask you the same questions as the online form and issue your number during the call.
Phone lines are open Monday through Friday, 7 a.m. to 10 p.m. Eastern time. Wait times are often shorter early in the morning or late in the afternoon. The IRS will mail you a formal confirmation letter within two weeks, but you can begin using your Tax ID immediately after the phone call.
Applying by Mail
If you prefer to apply by mail, download Form SS-4 from irs.gov, fill it out by hand or type it, and mail it to the IRS service center for your state. The IRS website lists the correct mailing address for each state. Include only the form itself — do not send supporting documents unless the IRS specifically requests them.
Processing by mail takes two to four weeks. The IRS will send you a letter with your Tax ID and a copy of your completed form. This method works if you are not in a hurry, but most people choose online or phone because they receive their number faster.
What Information You Will Need
Before you apply, gather these details. You will need them whether you apply online, by phone, or by mail. Having everything ready before you start speeds up the process and reduces errors that could delay your Tax ID.
| Information | Why the IRS Needs It |
|---|---|
| Your name and Social Security number | To identify you as the owner or responsible party |
| Business name (if different from your personal name) | To register the business entity with the IRS |
| Business address (physical location, not a PO box) | To locate the business for tax purposes |
| Business structure type | To determine tax filing requirements and rules |
| Description of what the business does | To classify the business for industry and tax purposes |
| Date you began or will begin business | To set the tax year and filing deadlines |
The IRS does not require you to have a business license, lease, or bank account before you apply. If you have not yet chosen a business address, you can use your home address or the address where you will conduct business.
After You Receive Your Tax ID
Once you have your Tax ID, use it on all business documents, tax forms, and correspondence with the IRS. Open a business bank account in the name of your business using your Tax ID — banks will not open a business account under a personal Social Security number. If you hire employees, you must use your Tax ID to report their wages and payroll taxes.
Keep your Tax ID number and confirmation letter in a secure place. You will need them to file annual tax returns, apply for business licenses, obtain business insurance, and handle any IRS correspondence. The Tax ID does not expire and remains valid as long as your business exists, even if you do not actively operate it.
Frequently Asked Questions
How long does it take to get a Tax ID?
Online applications issued during business hours (7 a.m. to 10 p.m. Eastern, Monday through Friday) give you your number immediately. Phone applications give you the number during the call. Mail applications take two to four weeks. Outside business hours, online applications receive their number by email within one business day.
Can I use my Social Security number instead of getting a Tax ID?
Only if you are a sole proprietor with no employees and no separate business structure. Most business types — LLCs, partnerships, corporations, and nonprofits — require a Tax ID. Even a single-owner LLC typically needs one to keep business and personal finances separate.
Do I need a business license before I can get a Tax ID?
No. The Tax ID is separate from a business license. You can obtain your Tax ID before you have a license, lease, or bank account. The IRS only needs to know that you intend to operate a business or organization.
What if I lose my Tax ID number?
Call the IRS at 1-800-829-4933 with your Social Security number and business name, and they will look up your number. You can also check your old tax returns or bank statements — your Tax ID appears on both. The IRS does not reissue confirmation letters, but you can request a transcript that includes your Tax ID.
Can I change my Tax ID if I change my business structure?
If you change from a sole proprietorship to an LLC or corporation, you need a new Tax ID. The IRS treats each business structure as a separate entity. File Form SS-4 again with your new structure type, and the IRS will assign a new number. Your old Tax ID becomes inactive but does not disappear from IRS records.