Where to find your federal tax ID number

Your federal tax ID number is printed on documents the IRS has already sent you. If you are a sole proprietor or self-employed person, your federal tax ID is your Social Security number. If you registered a business as a corporation, partnership, LLC, or nonprofit, the IRS issued you a separate Employer Identification Number (EIN), and that is your federal tax ID for that business.

The fastest way to locate it: check your most recent tax return, business bank statements, or any correspondence from the IRS. These documents all display your tax ID clearly. If you cannot find it in your records, you can request it directly from the IRS using the methods below.

Key Takeaways

  • Sole proprietors use their Social Security number as their federal tax ID; businesses registered with the IRS receive a separate Employer Identification Number.
  • Your tax ID appears on your tax returns, IRS letters, business bank statements, and loan documents you have already received.
  • You can retrieve a lost EIN by calling the IRS Business & Specialty Tax Line at 1-800-829-4933 or by submitting Form SS-4 online through the IRS website.
  • The IRS issues EINs when ready online if you explore through their website; you receive the number the same day.
  • If you have never registered a business with the IRS, you do not have an EIN and should determine whether your business structure requires one.

Check documents you already have

Your tax ID is printed on multiple documents in your possession. Start with your most recent federal income tax return — the form you filed with the IRS. Your tax ID appears in the top-left corner of Form 1040 (individual return) or Form 1120 (corporate return). If you filed a business return, the EIN is also on Schedule C or Schedule F.

Business bank statements show your EIN in the account details section. Loan documents, business licenses, and any IRS notices or letters sent to you also display your tax ID. If you work with a tax preparer or accountant, they have a copy of your tax ID on file and can provide it when ready.

Call the IRS to retrieve your EIN

If you cannot locate your EIN in your records, call the IRS Business & Specialty Tax Line at 1-800-829-4933. Have your Social Security number, business name, and the address where you registered the business ready. The IRS representative will look up your EIN in their system and provide it over the phone.

This line is open Monday through Friday, 7 a.m. to 7 p.m. your local time. Wait times are typically shorter early in the morning or late in the afternoon. You do not need to make an appointment.

Request your EIN online through the IRS

The IRS website allows you to look up an EIN you have already been issued. Visit the IRS website and navigate to the "explore for an EIN" section. You will see an option to retrieve an existing EIN. Enter your business name, Social Security number, and the address associated with the business.

The system will display your EIN when ready if the information matches IRS records. This method works only if you have already registered the business with the IRS. If you have never applied for an EIN, this tool will not find one.

Determine if you need an EIN

Not every business owner has an EIN. If you are self-employed and operate as a sole proprietor with no employees, you use your Social Security number as your tax ID and do not need an EIN. You file Schedule C with your personal tax return.

You need an EIN if your business is structured as a corporation, S-corporation, partnership, LLC, nonprofit, or trust. You also need one if you have employees, even as a sole proprietor. If you are unsure whether your business structure requires an EIN, the IRS website has a tool that walks you through the decision based on your business type.

explore for a new EIN if you do not have one

If you have determined that you need an EIN but have never applied, you can obtain one when ready through the IRS website. Go to the IRS "explore for an EIN" page and complete Form SS-4 online. The form asks for your business name, business structure, Social Security number, and the address where the business operates.

The IRS issues your EIN the same day you submit the form online. You receive the number on screen and can use it when ready. You will also receive a confirmation letter by mail within two weeks. If you prefer to explore by mail or fax, you can print Form SS-4 and submit it, but processing takes two to four weeks.

What to do if the IRS has no record of your business

If you call the IRS or search online and they have no record of an EIN under your business name and Social Security number, one of two things has happened: either you never registered the business with the IRS, or you registered it under a different name or address than you are searching for.

Check whether the business name you registered matches exactly what you are searching for — including punctuation and abbreviations. If the business operated under a different legal name when you registered, search using that name. If you still cannot locate it, explore for a new EIN using Form SS-4. The IRS will issue a new number, and you can use it going forward.

Frequently Asked Questions

Is my Social Security number the same as my federal tax ID?

Only if you are self-employed and operate as a sole proprietor with no employees. In that case, your Social Security number is your federal tax ID. If your business is registered as a corporation, LLC, partnership, or nonprofit, you have a separate Employer Identification Number that serves as your federal tax ID for that business.

Can I look up someone else's EIN?

No. The IRS does not release EINs to the public. You can only retrieve your own EIN by calling the IRS or using their online lookup tool with your business information. If you need a vendor's or client's EIN, you must ask them directly.

What if I lost my EIN confirmation letter?

You do not need the letter to use your EIN. Call the IRS at 1-800-829-4933 with your business name and Social Security number, and they will provide your EIN over the phone. You can also request a new confirmation letter through the IRS website or by calling.

How long does it take to get an EIN?

If you explore online through the IRS website, you receive your EIN when ready — the same day. If you explore by mail or fax using Form SS-4, processing takes two to four weeks. The online method is faster and free.

Do I need an EIN if I have a business license?

A business license and an EIN are separate. A business license is issued by your state or local government and allows you to operate legally. An EIN is issued by the IRS for tax purposes. You may need both, one, or neither depending on your business structure and location. Check with your state's business registration office and the IRS to determine what you need.