Your Tax ID is on documents you already have or can request for free

Your Tax ID number — also called an Employer Identification Number (EIN) if you own a business, or your Social Security Number (SSN) if you're an individual — appears on tax forms you've already filed or received. You don't need to search for it in a database. The IRS doesn't issue new numbers to people who already have one; they issue replacements only when you request them, and that takes weeks.

The fastest way to find your Tax ID is to look at a document you already have. If that document is gone, you can request a replacement from the IRS by mail or phone, but you'll need to prove who you are and wait for it to arrive.

Key Takeaways

  • Your Tax ID appears on your most recent tax return, W-2, 1099, or bank statements — check these first before contacting the IRS.
  • If you're self-employed or own a business, your EIN is on your business tax returns, business bank statements, or the IRS confirmation letter you received when you first registered.
  • The IRS will mail you a replacement Tax ID verification letter if you request one by phone at 1-800-829-1040 or by mail using Form SS-5 (for SSN) or Form 147-C (for EIN).
  • Requesting a replacement by mail takes four to six weeks; phone requests are faster but require you to answer security questions about your tax history.
  • You do not need to pay anyone to help you find your Tax ID — the IRS provides this service free.

Check documents you already have at home

Start by looking through papers you have on hand. Your Tax ID appears on multiple documents, and you likely have at least one:

  • Your most recent tax return (Form 1040, 1040-SR, or 1040-NR): Your SSN is printed at the top of the first page.
  • W-2 forms from your employer: Your SSN appears in box a (the employee's SSN box) on the left side of the form.
  • 1099 forms (1099-NEC, 1099-MISC, 1099-INT, etc.): Your SSN or EIN appears in box 5 on the left side.
  • Bank or investment account statements: Banks sometimes print your SSN on statements, usually at the bottom or in the account details section.
  • Mortgage or loan documents: Lenders print your SSN on promissory notes and closing statements.
  • IRS correspondence: Any letter from the IRS — including notices, refund letters, or payment plans — has your SSN or EIN printed on it.

If you own a business or are self-employed, your EIN also appears on your business tax returns (Form 1120, 1120-S, 1065, or 1040 Schedule C), business bank statements, and the IRS confirmation letter you received when you first registered your business.

Request a replacement from the IRS by phone

If you cannot find your Tax ID in any document, you can call the IRS directly. The phone line is free and available year-round, though wait times are longer during tax season (January through April).

Call 1-800-829-1040 and tell the representative you need to verify your Tax ID. Have your name, date of birth, and current address ready. The IRS will ask you security questions about your tax history — such as the amount of your last refund, the year you filed a particular return, or information from a W-2 — to confirm you are who you say you are. If you answer correctly, the representative will read your Tax ID to you over the phone. You can write it down immediately.

This call is free, but you may wait 30 minutes to two hours during busy periods. The IRS does not offer callback options, so you'll need to stay on the line.

Request a replacement by mail using IRS forms

If you prefer not to call or cannot reach the IRS by phone, you can request a Tax ID verification letter by mail. The letter will contain your Tax ID and can be used as proof of your number.

For a Social Security Number (SSN), use Form SS-5 (Application for a Social Security Card). You can download it from ssa.gov or request it by phone at 1-800-772-1213. Fill out the form, include a copy of your birth certificate or passport, and mail it to your local Social Security Administration office. Processing takes four to six weeks.

For an Employer Identification Number (EIN), use Form 147-C (Application for IRS Individual Identification Number). Download it from irs.gov, fill it out, and mail it to the IRS address listed on the form. Include a copy of your business registration documents or articles of incorporation if you have them. Processing also takes four to six weeks.

What to do if you've lost documents and can't remember your number

If you don't have any documents and can't reach the IRS by phone, your next step is to visit an IRS office in person. You can find the nearest office at irs.gov/localoffices. Bring a government-issued photo ID (driver's license or passport) and proof of your current address (a utility bill or lease dated within the last 60 days). An IRS representative can look up your Tax ID on the spot and print a verification letter for you.

Walk-in hours vary by location, and some offices require appointments. Call ahead before you go. This option is faster than mail but may require travel to your nearest IRS office.

Understand the difference between SSN and EIN

If you work as an employee, your Tax ID is your Social Security Number (SSN) — a nine-digit number issued by the Social Security Administration. You received it when you were born or when you first moved to the United States. You use the same SSN for all tax purposes throughout your life.

If you own a business, operate as a sole proprietor, or are self-employed, you may also have an Employer Identification Number (EIN) — a nine-digit number issued by the IRS. An EIN is separate from your SSN and is used only for business tax purposes. You register for an EIN when you start a business, and the IRS assigns it to you immediately. Many sole proprietors use their SSN instead of an EIN, but some choose to register for an EIN to keep their business finances separate.

If you're unsure which number you need, check the form or document that asked for it. Most personal tax forms ask for your SSN. Business tax forms ask for an EIN, though they may accept an SSN if you don't have an EIN.

Frequently Asked Questions

Can I look up my Tax ID online without calling the IRS?

The IRS does not have a public online lookup tool for Tax IDs. You must call 1-800-829-1040, visit an IRS office in person, or request a replacement by mail. Some third-party websites claim to offer this service, but they cannot access IRS records and should not be trusted with your personal information.

What if I'm not a U.S. citizen or don't have a Social Security Number?

If you work in the United States but don't have an SSN, you can apply for an Individual Taxpayer Identification Number (ITIN) using Form W-7. An ITIN is a nine-digit number issued by the IRS for tax purposes only. You can download Form W-7 from irs.gov or request it by calling 1-800-829-1040. Processing takes two to three weeks.

Do I need to pay someone to help me find my Tax ID?

No. The IRS provides Tax ID verification for free by phone, mail, and in person. You do not need to pay a tax preparer, identity verification service, or any other company to find your Tax ID. If someone charges you for this service, they are taking advantage of you.

What if I think someone else is using my Tax ID?

If you suspect identity theft or that someone has used your Tax ID without permission, contact the IRS immediately at 1-800-829-1040 and file a report with the Federal Trade Commission at identitytheft.gov. You may also want to place a fraud alert with the three major credit bureaus (Equifax, Experian, and TransUnion).

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

Replacement Tax ID verification letters take four to six weeks to arrive by mail. If you need your Tax ID sooner, call the IRS at 1-800-829-1040 or visit an IRS office in person. Both options are faster than mail.