Your Tax ID is on documents you already have at home

Your Tax ID number — also called an Employer Identification Number (EIN) or Individual Taxpayer Identification Number (ITIN) — appears on multiple documents you receive from the IRS or your employer. You do not need to request it or contact anyone. The number was assigned to you when you filed your first tax return or when your employer registered with the IRS, and it stays the same unless you apply for a new one.

The fastest way to find it is to look at documents already in your files. If you cannot locate it that way, the IRS has a phone line and an online tool that can tell you what it is.

Key Takeaways

  • Your Tax ID appears on your most recent tax return, W-2 form, 1099 form, or IRS notice — check these documents first.
  • If you are self-employed or own a business, your EIN is on your business tax returns and any IRS correspondence about your business.
  • The IRS can confirm your Tax ID by phone at 1-800-829-1040 if you have your Social Security Number and other identifying information ready.
  • An ITIN (for non-citizens) appears on your ITIN assignment notice and any tax returns you filed using that number.

Check your tax returns and W-2 forms first

Your most recent tax return is the easiest place to find your Tax ID. If you filed a federal return in the past three years, look at the top of Form 1040 (the main individual tax return form). Your Social Security Number appears there, and that is your Tax ID for personal tax purposes.

If you are an employee, your W-2 form (Wage and Tax Statement) also shows your Social Security Number in the same location. Your employer sends this to you by January 31 each year if you worked there during the previous year. Check your files for the most recent W-2 you received.

If you are self-employed or received income from sources other than an employer, look for Form 1099 (various types exist — 1099-NEC, 1099-MISC, 1099-INT, and others). These forms show your Social Security Number and are sent by the person or business that paid you.

Find your EIN if you own a business

If you own a business or are a sole proprietor, you may have an Employer Identification Number (EIN) separate from your Social Security Number. An EIN is a nine-digit number formatted as XX-XXXXXXX. You received an EIN assignment notice (Form SS-4) from the IRS when you first registered your business.

Look for this notice in your business files or tax records. It typically arrived by mail within two weeks of your application. If you filed business tax returns (Form 1120, 1120-S, 1065, or 1040-C), your EIN appears at the top of those forms.

Any letter or notice from the IRS about your business also shows your EIN. Check your files for correspondence from the IRS dated after you started your business.

Locate your ITIN if you are not a U.S. citizen

If you are not a U.S. citizen and do not have a Social Security Number, you may have an Individual Taxpayer Identification Number (ITIN). An ITIN is a nine-digit number formatted as 9XX-XX-XXXX. You received an ITIN assignment notice (Form W-7) from the IRS when your ITIN was created.

Look for this notice in your records. It shows your ITIN clearly and was sent to you by mail. If you have filed tax returns using your ITIN, that number appears on those returns as well. Any IRS notice or letter sent to you about your tax account will also display your ITIN.

Contact the IRS if you cannot find your number

If you have searched your documents and cannot locate your Tax ID, you can call the IRS directly. The main IRS phone line is 1-800-829-1040. Have your Social Security Number, date of birth, and filing status ready when you call. Wait times are often long, especially during tax season (January through April).

You can also use the IRS online tool called Get Transcript at irs.gov. This tool lets you view your tax account information, including your Tax ID, without calling. You will need to verify your identity using a phone number, email address, or by answering security questions based on your credit history.

If you are looking for a business EIN, you can search the IRS Business Services Online at irs.gov/ein. This tool shows you whether an EIN has been issued and when.

What to do if your Tax ID was lost or compromised

If you believe your Social Security Number or ITIN has been used fraudulently or compromised, contact the IRS Identity Theft Hotline at 1-800-908-4490. You can also file Form 14039 (Identity Theft Affidavit) with the IRS by mail or through your online account.

For a business EIN that may have been compromised, contact the IRS at 1-800-829-1040 and explain the situation. The IRS can issue you a new EIN if necessary, though this is uncommon and usually only done in cases of identity theft.

If your Tax ID documents were destroyed in a fire, flood, or other disaster, the IRS can issue replacement documents. Call 1-800-829-1040 to request copies of your IRS notices or transcripts.

Frequently Asked Questions

Is my Social Security Number the same as my Tax ID?

For most individuals, yes. Your Social Security Number is your Tax ID for personal tax purposes. However, if you own a business, you may also have a separate EIN. If you are not a U.S. citizen, your ITIN is your Tax ID instead of a Social Security Number.

How long does it take to get a Tax ID if I do not have one?

If you need an EIN for a new business, you can receive one immediately by applying online at irs.gov. If you apply by phone or mail, it takes about two weeks. An ITIN typically takes four to six weeks after you submit Form W-7 with your tax return.

Can I have more than one Tax ID?

You can have one Social Security Number and one ITIN, but not both. You can have multiple EINs if you own multiple businesses or if you change your business structure. Each business entity gets its own EIN.

What if I lost my IRS assignment notice?

You do not need the original notice. Your Tax ID appears on any tax return you filed, any W-2 or 1099 form you received, or any IRS letter sent to you. You can also request a transcript from the IRS that shows your Tax ID.