Where to find your Federal Tax ID Number

Your Federal Tax ID Number — also called an Employer Identification Number (EIN) or Individual Taxpayer Identification Number (ITIN) — appears on documents the IRS has already sent you. The fastest way to locate it is to check paperwork you have at home rather than contact the IRS.

If you have a Social Security Number and file taxes as an individual, your SSN is your Federal Tax ID. If you operate a business, nonprofit, or partnership, you have a separate nine-digit EIN. If you are not a U.S. citizen and file taxes, you have an ITIN. Each type appears in different places depending on what you filed and when.

Key Takeaways

  • Your Federal Tax ID is on your most recent tax return, W-2, 1099, or IRS letter — check these documents first before contacting anyone.
  • If you filed taxes as an individual, your Social Security Number is your Federal Tax ID; businesses and nonprofits have a separate nine-digit EIN.
  • The IRS can confirm your number by phone at 1-800-829-1040 if you have your SSN, EIN paperwork, or recent tax documents ready.
  • If you lost an EIN or ITIN, the IRS can issue a replacement, but the process takes several weeks and requires proof of what you originally filed.

Documents that show your Federal Tax ID

Start by gathering tax paperwork from your home. Your Federal Tax ID appears on the first page of any tax return you filed — look at the top left corner of Form 1040 (individual return), Form 1120 (business return), or Form 990 (nonprofit return). If you filed in the last three years, the IRS website lets you view a transcript of your return, which also displays your number.

If you received a W-2 from an employer, your SSN appears in box a on the left side. If you received a 1099 (for freelance or contract work), your SSN or EIN is in box 1. Any letter from the IRS — including notices about taxes owed, refunds, or account changes — displays your Federal Tax ID at the top or in the body of the letter. If you applied for an EIN for a business, the IRS sent you a confirmation letter (Form SS-4) with the number in the upper right corner.

How to view your tax return online

The IRS allows you to view your tax return transcript without mailing anything or calling. Go to irs.gov and select "Get Your Tax Record" under the Tools section. You will need to verify your identity by providing your SSN, date of birth, filing status, and the mailing address on your most recent return.

The IRS offers two types of transcripts: a Tax Return Transcript (which shows what you reported on your return) and an Account Transcript (which shows payments and adjustments the IRS made). Both display your Federal Tax ID. The transcript appears on screen immediately after you verify your identity, and you can print or download it as a PDF. This method works for returns filed in the last three years.

Contacting the IRS by phone

If you cannot locate your Federal Tax ID in your documents and cannot access the online transcript, call the IRS at 1-800-829-1040. Have your SSN, date of birth, and filing status ready. The IRS can confirm your number over the phone if you can answer security questions about your account.

Wait times are longest during tax season (January through April). If you call outside those months, you may reach someone more quickly. The IRS also offers a callback option — you can request a call at a specific time rather than wait on hold. Tell the representative you need to confirm your Federal Tax ID, and they will verify your identity before providing the number.

Replacing a lost EIN or ITIN

If you operated a business or nonprofit and lost your EIN, the IRS can issue a replacement. You do not need to apply for a new one — the same number stays with your business for life. Call 1-800-829-4933 (the business line) with your business name, address, and the year you first received the EIN. The representative will confirm the number and can mail you a new copy of your original Form SS-4 confirmation letter.

If you have an ITIN and need to confirm or replace it, call 1-800-829-1040 with your ITIN, date of birth, and country of citizenship ready. The IRS can reissue an ITIN if it has expired or if you lost the documentation. The process takes four to six weeks by mail. You will need to file Form W-7 (Application for IRS Individual Taxpayer Identification Number) and provide proof of identity and foreign status.

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

If you call the IRS and they cannot find a Federal Tax ID under your name, it means either you never filed taxes, never applied for an EIN, or the information you provided did not match their records. Ask the representative to search using different variations of your name (maiden name, nickname, legal name) or different addresses where you may have lived when you filed.

If you filed taxes years ago and the IRS still has no record, request a copy of your return from the IRS by mail. Fill out Form 4506-C (Request for Copy of Tax Return) and mail it to the address listed on the form for your state. Include a check for the copying fee (usually $50 to $75 per return). The IRS will mail you a certified copy of your return, which displays your Federal Tax ID. This process takes 30 to 60 days.

Frequently Asked Questions

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

If you file taxes as an individual and do not own a business, yes — your SSN is your Federal Tax ID. If you own a business, partnership, or nonprofit, you have a separate nine-digit EIN in addition to your SSN. The EIN is used only for business tax purposes.

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

No. The IRS does not release Federal Tax IDs for other people. If you need a business's EIN (for example, to report income you paid them), you can request it directly from the business, or search the IRS Tax Exempt Organization Search if it is a nonprofit.

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

If you call the IRS, they can confirm your existing number immediately and mail you a replacement confirmation letter within two weeks. If you need a new EIN or ITIN (not a replacement), the process takes four to six weeks by mail or one business day if you apply by phone.

What if I never received my EIN confirmation letter?

Call the IRS business line at 1-800-829-4933 with your business name and address. They can confirm your EIN and mail you a new copy of Form SS-4. If you applied for an EIN online, you received the number immediately on screen — check your email for any confirmation you may have saved.