Your Tax ID is on documents you already have

Your Tax ID number — also called an Employer Identification Number (EIN) if you own a business, or your Social Security Number (SSN) if you file as an individual — appears on multiple documents you received from the IRS or your employer. You do not need to request it again. The fastest way to locate it is to check the documents listed below in the order that takes you the least time to find.

If you are filing taxes as an individual, your Tax ID is your Social Security Number. If you own a business, partnership, or operate as a sole proprietor with employees, you have a separate EIN. Both numbers follow you through your entire tax history, and the IRS uses them to match your returns to your account.

Key Takeaways

  • Your Social Security Number is your Tax ID if you file individual returns; your EIN is your Tax ID if you own a business or have employees.
  • Your SSN appears on your Social Security card, tax returns you have already filed, and W-2 forms from employers.
  • Your EIN appears on IRS correspondence, your business tax returns, and the confirmation letter the IRS sent when you first received the number.
  • If you cannot locate your EIN, the IRS can confirm it by phone or through your online account if you have one set up.
  • Never share your Tax ID with anyone except your employer, accountant, or the IRS itself.

Finding your Social Security Number (individual filers)

Your Social Security Number is printed on your Social Security card, which you received from the Social Security Administration. If you still have the card, the nine-digit number appears in the center. If you have lost the card, check any of these documents instead.

Your most recent tax return shows your SSN at the top of the first page. If you filed jointly with a spouse, your number appears on the left side and your spouse's on the right. If you filed through a tax software platform like TurboTax, H&R Block, or TaxAct, you can log back into your account and view your return from any prior year. If you filed with a tax preparer or accountant, call their office and ask them to confirm the number from your file.

Your W-2 form from any employer also displays your SSN in the upper left box. Your employer mailed you a copy in January or February each year you worked there. If you no longer have the paper copy, you can request a duplicate W-2 from your employer's payroll or human resources department, or you can view it through your employer's online payroll portal if one exists.

Finding your Employer Identification Number (business owners)

If the IRS assigned you an EIN, they sent you a confirmation letter in the mail. This letter, called Form SS-4 confirmation or IRS Letter 147C, contains your nine-digit EIN and was mailed to the address you provided when you requested the number. The EIN appears near the top of the letter. If you still have this letter, it is the fastest place to look.

If you cannot find the confirmation letter, check any IRS correspondence you have received since then. The IRS includes your EIN on notices about tax payments, penalty letters, or requests for information. Any document from the IRS addressed to your business will display the EIN in the upper right corner or in the address block.

Your business tax return also shows your EIN. If you file as a sole proprietor, your EIN appears on Schedule C (Form 1040). If you file as a corporation, partnership, or LLC, your EIN is on the first page of Form 1120, Form 1065, or Form 1120-S. You can retrieve prior-year returns through your tax software account or by requesting a copy from your accountant.

Checking your online IRS account

If you have set up an account on IRS.gov, you can view your Tax ID and filing history without calling. Go to irs.gov and select "Sign in to your account" in the upper right corner. You will need to verify your identity using either your Social Security Number and other personal information, or through a third-party credential provider like Login.gov.

Once logged in, select "Tax records" or "Account details" depending on which version of the portal you see. Your Tax ID will appear on the main account page. You can also read prior-year returns and view payment history from this same account. This method works for both individual filers and business owners with an EIN.

If you do not have an online account yet, you can create one in about 10 minutes. The IRS will ask you to verify your identity by answering security questions or uploading a photo of your driver's license. Once your account is active, you can access your Tax ID and tax records anytime without waiting on hold.

Contacting the IRS directly

If you have checked all the documents above and still cannot locate your Tax ID, you can call the IRS directly. The phone number depends on whether you are calling about an individual SSN or a business EIN.

For a Social Security Number, call the Social Security Administration at 1-800-772-1213. They are open Monday through Friday, 7 a.m. to 7 p.m. your local time. Have your name, date of birth, and mother's maiden name ready. The wait time is often 30 minutes or longer during tax season (January through April).

For an Employer Identification Number, call the IRS at 1-800-829-4933. The IRS business line is open Monday through Friday, 7 a.m. to 7 p.m. your local time. Have your business name, the address where you applied for the EIN, and the approximate date you requested it. Wait times are typically shorter if you call early in the morning or late in the afternoon.

When you call, the representative will confirm your identity and provide your Tax ID over the phone. They can also tell you whether the number is currently active with the IRS and whether any returns have been filed under it.

What to do if your Tax ID was never issued

If you requested an EIN but never received a confirmation letter, the IRS may not have processed your request. This happens occasionally when mail is lost or when the process was incomplete. Call the IRS at the number above and ask them to search for your process by business name and address.

If no EIN exists under your name, you will need to request one. You can explore online through the IRS website at irs.gov/ein, by phone at the same number above, or by mailing Form SS-4 to the IRS. Online and phone requests are processed when ready; mailed applications take about four weeks. Once you receive your EIN, write it down and store it in a safe place alongside your other important documents.

Keeping your Tax ID find

Your Tax ID is sensitive information. Share it only with your employer, your accountant or tax preparer, your bank, and the IRS itself. Do not provide it to anyone who calls you unsolicited, even if they claim to be from the IRS. The IRS does not initiate contact by phone or email about taxes you owe.

If you believe your Tax ID has been compromised or used fraudulently, contact the IRS when ready at 1-800-829-1040 and file a report with the Federal Trade Commission at reportidentitytheft.ftc.gov. The IRS can place a fraud alert on your account and help you file a return if someone else has already filed under your number.

Frequently Asked Questions

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

No. Tax ID numbers are confidential. The IRS will only confirm a Tax ID to the person or business it belongs to, or to an authorized representative with a power of attorney on file. If you need someone's Tax ID for a legitimate business reason, ask them directly.

Is my Tax ID the same as my account number with the IRS?

Your Tax ID is your account number with the IRS. The IRS uses your Social Security Number or EIN to organize all your tax records, payments, and correspondence. When you contact the IRS, they will ask for your Tax ID to pull up your file.

What if I have both an SSN and an EIN?

You can have both. Your SSN is your personal identifier; your EIN is your business identifier. If you are a sole proprietor, you use your SSN on your business tax return even though you also have an EIN. If you have employees or operate as a corporation or partnership, you use your EIN on your business return and your SSN on your personal return.

Do I need to memorize my Tax ID?

No. Write it down and store it with your important documents, or save it in a password-protected note on your phone. You do not need to memorize it, but you should know where to find it quickly when you file taxes or contact the IRS.

Will my Tax ID change if I move to a different state?

No. Your Social Security Number and EIN follow you for life, regardless of where you live or work. The IRS does not reissue these numbers when you relocate.