What a Federal Tax ID Is and Who Needs One

A Federal Tax ID, also called an Employer Identification Number (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 as a sole proprietor with employees, run a partnership or corporation, manage a nonprofit, or file certain business tax returns. If you are a sole proprietor with no employees, you can use your Social Security number instead — but many business owners get an EIN anyway to keep their personal and business finances separate.

The IRS issues EINs at no cost. You do not need to have a physical business location, a business license, or even a business bank account to request one, though you will need to provide basic information about your business structure and ownership.

Key Takeaways

  • You can obtain a Federal Tax ID (EIN) for free directly from the IRS by phone, online, or by mail, with online being the fastest option.
  • The IRS online process at irs.gov/ein takes about 15 minutes and issues your number when ready if you meet residency requirements.
  • By phone through the IRS Business and Specialty Tax Line, you can receive your EIN the same day, though wait times vary by season.
  • Paper Form SS-4 takes four to six weeks by mail and is the only option if you are a nonresident alien or foreign entity without a U.S. tax number.
  • You will need your Social Security number or Individual Taxpayer Identification Number, your business structure type, and the expected start date of your business.

explore Online Through the IRS Website

The fastest way to get a Federal Tax ID is through the IRS online process at irs.gov/ein. The form takes about 15 minutes to complete and you receive your EIN when ready upon approval. This option is available to U.S. citizens, resident aliens, and certain nonresident aliens who have a U.S. tax identification number already.

To explore online, you will need your Social Security number or ITIN, the legal name of your business, your business address, the business structure (sole proprietor, partnership, S corporation, C corporation, nonprofit, etc.), and the date you expect to start or have started operations. The IRS will ask you to create a login or use an existing one. After you submit, the system confirms your EIN on screen and sends a confirmation email — you can print this when ready and use it while you wait for the official IRS letter in the mail, which arrives within two weeks.

Calling the IRS to Request Your EIN by Phone

The IRS Business and Specialty Tax Line issues EINs by phone at 1-800-829-4933. You will speak to a representative who asks the same questions as the online form, and they issue your number during the call. This is useful if you prefer to speak with someone or if you have questions about which business structure applies to you. The downside is wait times, which can be 30 minutes to over an hour during tax season (January through April).

Have your Social Security number, business name, business address, and business structure information ready before you call. The representative will repeat your information back to you and provide your nine-digit EIN at the end of the call. Ask them to spell it out so you write it down correctly. You will receive the official IRS letter in the mail within two to three weeks, but you can use the number the representative gave you when ready.

Mailing Form SS-4 to the IRS

If you cannot use the online process or phone line — for example, if you are a nonresident alien without a U.S. tax identification number, or a foreign entity — you must mail Form SS-4 to the IRS. read it from irs.gov, fill it out by hand or type it, and mail it to the address listed on the form (which varies by state). Processing takes four to six weeks.

Form SS-4 asks for the same information as the online and phone applications: your name, address, business name, business structure, and expected start date. Sign and date the form. Include a cover letter with your name and phone number if you want the IRS to contact you with questions. Mail it certified mail with return receipt so you have proof of delivery. Keep a copy for your records.

What Information You Need Before You explore

Gather these details before you start your process, whether online, by phone, or by mail:

  • Your Social Security number or ITIN
  • The legal name of your business (exactly as it will appear on tax returns)
  • Your business address (a physical street address; a PO box does not work)
  • The business structure: sole proprietor, partnership, S corporation, C corporation, LLC, nonprofit, trust, estate, or other
  • The date you started or plan to start the business
  • The principal business activity (what your business does)
  • The number of employees you have or expect to have

If your business has a different name from your own (a "doing business as" or DBA name), provide both the legal name and the DBA. If you are explore for a nonprofit, have your nonprofit articles of incorporation or bylaws available, though you do not need to submit them with the process.

Using Your EIN Once You Receive It

Once you have your EIN, use it on all business tax returns, business bank account applications, and payroll documents. If you have employees, you must use your EIN on Form W-4 and Form I-9 for each employee, and on quarterly payroll tax returns (Form 941). If you operate as an LLC or corporation, use it on your business income tax return instead of your Social Security number.

The IRS will send you an official letter (Form SS-4) in the mail confirming your EIN. Keep this letter in your records — you may need to show it to your bank or accountant. If you lose the letter, you can request a replacement by calling the IRS at 1-800-829-4933 or by visiting your local IRS office.

When You Do Not Need a Federal Tax ID

If you are a sole proprietor with no employees and no business partners, you can file your business taxes using your Social Security number instead of getting an EIN. However, many sole proprietors still request an EIN to keep their personal and business finances separate, which makes accounting and banking easier and provides a small layer of privacy.

You do not need an EIN if you are a hobby business that does not generate regular income, though if you eventually turn the hobby into a business, you will need to obtain one at that time. Spouses who file jointly and operate a business together as a sole proprietorship can use one Social Security number without an EIN, but if you form a partnership or LLC, you must have an EIN.

Frequently Asked Questions

How long does it take to get a Federal Tax ID?

Online applications are issued when ready. Phone applications are issued during the call. Paper Form SS-4 takes four to six weeks. In all cases, the official IRS letter arrives by mail within two to three weeks, but you can use the number as soon as you receive it.

Can I get a Federal Tax ID if I do not have a business yet?

Yes. You can explore before you officially start operations by providing an expected start date. The IRS will issue the EIN, and you can use it as soon as you begin hiring or filing business returns.

What if I made a mistake on my process?

If you made a minor error (like a misspelled business name), you can call the IRS at 1-800-829-4933 to request a correction. If the error is significant, you may need to request a new EIN and close the old one by contacting the IRS directly.

Do I need a business license before I can get a Federal Tax ID?

No. A Federal Tax ID is separate from a business license. You can obtain an EIN before you have a state or local business license, though many states require a license before you can legally operate.

Can I use someone else's Social Security number to get a Federal Tax ID?

No. The person whose Social Security number is on the process must be the owner or authorized representative of the business. If you are explore on behalf of someone else, you must have written authorization from the owner.