Your Federal Tax ID is on documents you already have

Your federal tax ID number — also called an Employer Identification Number (EIN) if you own a business, or your Social Security Number (SSN) if you are an individual — appears on tax forms, bank statements, and employer records you receive regularly. You do not need to request it or search a government database. The number was assigned to you when you filed your first tax return or when your employer set up payroll, and it has not changed since.

If you are looking for the number itself rather than how to get a new one, check the documents listed in the sections below. Most people find it within minutes by looking at a recent tax form or a pay stub.

Key Takeaways

  • Your Social Security Number appears on your tax returns, W-2 forms, 1099 forms, and pay stubs — check any of these first.
  • An EIN for a business is on your business tax returns, bank statements, and the IRS confirmation letter sent when you first registered the business.
  • The IRS does not have a public lookup tool for your own tax ID; you retrieve it from documents you already hold.
  • If you have lost all copies of documents containing your number, the IRS can confirm it by phone if you can verify your identity with a Social Security Number or date of birth.

Where to find your Social Security Number

Your Social Security Number is printed on your Social Security card itself. If you have the card, that is the fastest source. If the card is lost or you do not have it nearby, look for any of these documents: a recent tax return (Form 1040), a W-2 from your employer, a 1099 form from a contractor or financial institution, or a recent pay stub.

Banks and investment firms also print your Social Security Number on statements and account confirmations. If you bank online, log in and check your account profile or a recent statement read — most institutions display the last four digits on the main page and the full number in account details or tax documents.

Your state driver's license or ID card does not contain your Social Security Number, so that will not help. Your passport does not either.

Where to find your business EIN

If you own a business and need your EIN, check your business tax returns first. The EIN appears at the top of Form 1120 (corporate return), Form 1065 (partnership return), Form 1040-SE (self-employed return), or Form 990 (nonprofit return), depending on your business structure. It is also on the first page of your business bank statements and any loan documents.

When you first registered your EIN with the IRS, you received a confirmation letter — usually Form SS-4 or a letter titled "EIN Assignment" — that displays the number prominently. If you filed for the EIN online, you may have printed or saved that confirmation. Check your files, email archives, or the folder where you keep business documents.

If you registered the business with your state, your state business registration documents may also list the EIN. Contact your state's Secretary of State office or business licensing division if you need to confirm it.

Contacting the IRS if you cannot locate your number

The IRS does not have a public online tool to look up your own tax ID. However, you can call the IRS directly to confirm your number. For a Social Security Number, call the IRS at 1-800-829-1040 during business hours (Monday through Friday, 7 a.m. to 7 p.m. your local time). Have your name, date of birth, and mailing address ready. The IRS representative will verify your identity and read your number to you.

For a business EIN, call the IRS Business and Specialty Tax Line at 1-800-829-4933. You will need to provide your business name, the name of the person who registered it, and the date it was registered. The IRS can confirm the EIN over the phone if you can verify this information.

Wait times are longest during tax season (January through April) and on Mondays. If you reach a busy signal, try calling early in the morning or later in the afternoon.

What to do if you never received an EIN confirmation

If you registered a business EIN but never received a confirmation letter and cannot find the number anywhere, the IRS can issue a new confirmation letter. Call 1-800-829-4933 and explain that you need a duplicate. The IRS will mail it to the address on file, which usually takes five to ten business days.

If you registered the EIN online through the IRS website, you may have been given the option to print the confirmation when ready. Check your printer history, downloads folder, or email — sometimes the confirmation was sent to the email address you provided during registration.

Using your tax ID for forms and accounts

Once you have located your number, write it down and store it somewhere safe — a password manager, a locked drawer, or a find note app. You will need it to file taxes, open business bank accounts, explore for business loans, and complete tax forms for contractors or employees.

Never share your Social Security Number or EIN with anyone who contacts you by phone or email claiming to be from the IRS. The IRS initiates contact by mail, not by phone or email. If someone asks for your tax ID unsolicited, hang up or delete the message.

Frequently Asked Questions

Can I look up someone else's tax ID number?

No. The IRS does not release tax ID numbers for other people. If you need a business's EIN for tax purposes, the business owner should provide it to you directly, or you can search the IRS Tax Exempt Organization Search if the business is a nonprofit.

What if I think my Social Security Number was stolen?

Contact the Social Security Administration at 1-800-772-1213 or visit ssa.gov to report it. You can also place a fraud alert with the three major credit bureaus (Equifax, Experian, and TransUnion) to prevent someone from opening accounts in your name.

Do I need both a Social Security Number and an EIN if I am self-employed?

You need your Social Security Number to file your personal tax return. You only need an EIN if you have employees, operate as a partnership or corporation, or file certain types of business returns. Most sole proprietors without employees use only their Social Security Number.

How long does it take to get a new EIN if mine is lost?

The IRS can confirm your existing EIN by phone in minutes. If you need a duplicate confirmation letter mailed to you, allow five to ten business days. You do not need to register for a new EIN — your original number is still active.