Your Tax ID is on documents you already have
Your tax ID number — also called an Employer Identification Number (EIN) if you run a business, or your Social Security Number (SSN) if you're an individual — appears on paperwork the IRS has already sent you. You don't need to request it again. The fastest way to find it is to check documents from your last tax return, your employer, or your bank.
If you've never filed taxes and don't have those documents, you can request a new one from the IRS. The process depends on whether you need an SSN (which comes from Social Security, not the IRS) or an EIN (which the IRS issues).
Key Takeaways
- Your SSN appears on your Social Security card, tax returns, W-2 forms, and bank statements — check these first before requesting a new one.
- An EIN for your business is on IRS correspondence, your business bank account paperwork, and any tax documents you've filed.
- If you've lost your SSN, Social Security Administration (not the IRS) issues replacements by mail or in person at a local office.
- If you need an EIN and have never received one, you can request it from the IRS by phone, mail, or online through their Business Services Online portal.
- The IRS will not call, email, or text you asking for your tax ID — any contact claiming to be the IRS asking for this information is a scam.
Where to look for your Social Security Number
Your SSN is printed on your Social Security card itself. If you have that card, the nine-digit number is right there. If the card is lost or damaged, check other documents: your most recent tax return (Form 1040), any W-2 form from an employer, your driver's license or state ID, bank statements, or mortgage paperwork.
Many people find their SSN fastest by logging into their bank's website or app — it often appears on account statements or in the account details section. If you filed taxes last year, you can also view your return through the IRS website using their transcript tool, which shows your SSN.
Where to look for your Employer Identification Number
If you own a business and have an EIN, it appears on IRS letters sent to your business address — usually the letter you received when you first got the number. Check your business bank account paperwork; the EIN is often listed there. If you filed business tax returns (Form 1120, 1120-S, 1065, or 990), the EIN is on the first page.
You can also look at your business license, payroll records, or any correspondence from the IRS addressed to your business. If you've set up a business but never received an EIN, you'll need to request one.
How to request a new Social Security Number
The Social Security Administration, not the IRS, issues SSNs. If you've never had one or need a replacement, you can visit your local Social Security office in person or request one by mail. To find your nearest office, go to ssa.gov and use their office locator tool.
To request an SSN by mail, you'll need to send the Social Security Administration original or certified copies of documents proving your age, identity, and citizenship or immigration status. The list of acceptable documents is on their website. Processing by mail takes two to four weeks. In-person appointments are usually faster — many offices can issue a replacement card the same day or within a few days.
How to request a new Employer Identification Number
If you own a business and need an EIN, the IRS offers three ways to request one. The fastest is by phone: call the IRS Business and Specialty Tax Line at 1-800-829-4933. You'll answer questions about your business, and they'll issue the number immediately over the phone. You can then use it right away.
You can also request an EIN online through the IRS Business Services Online portal at irs.gov. This takes about 15 minutes and you receive your number immediately. If you prefer to mail a request, you can send Form SS-4 to the IRS address listed on the form itself; processing takes about four weeks.
What documents you'll need to request a tax ID
| Type of Request | Where to Request | Documents Needed | Processing Time |
|---|---|---|---|
| Social Security Number (new or replacement) | Social Security Administration office or by mail | Proof of age, identity, and citizenship or immigration status (original or certified copies) | Same day (in person) or 2–4 weeks (by mail) |
| Employer Identification Number | IRS by phone, online, or by mail | Form SS-4 (by mail only); by phone or online, answer questions about your business | Immediate (phone or online) or 4 weeks (by mail) |
Protecting your tax ID from scams
The IRS will never call, email, or text you asking for your SSN or EIN. If someone contacts you claiming to be from the IRS and asks for your tax ID, it is a scam. Hang up or delete the message. The real IRS contacts people by mail first, and only after you've had a chance to respond in writing.
Do not share your tax ID with anyone who calls you unsolicited, even if they claim to be from a government agency, your bank, or your employer. Legitimate organizations already have your tax ID on file. If you're unsure whether a call is real, hang up and call the organization directly using a phone number from their official website or your account statement.
Frequently Asked Questions
Can I use my tax ID number before I receive official documentation?
Yes. If you received your SSN or EIN over the phone from the IRS or Social Security Administration, you can use that number immediately for tax purposes, employment, or opening a bank account. You don't have to wait for a card or letter to arrive in the mail.
What if I have multiple tax ID numbers?
If you're an individual, you should have only one SSN. If you've been issued more than one, contact the Social Security Administration to report it. If you own multiple businesses, each business can have its own EIN. This is normal and expected.
Do I need to pay to get a replacement tax ID?
No. The Social Security Administration and the IRS do not charge for issuing or replacing an SSN or EIN. If someone asks you to pay for this service, it is a scam.
How long does it take to receive a replacement Social Security card in the mail?
The Social Security Administration typically mails replacement cards within 7 to 10 business days after you submit your request in person. If you request by mail, add time for your documents to reach them first — usually 2 to 4 weeks total.
Can I look up someone else's tax ID number?
No. Tax ID numbers are private. You cannot look up another person's SSN or a business's EIN through a public database. If you need a business's EIN for legitimate reasons (like paying them), ask them directly.