Your Tax ID is on documents you already have or can request from the IRS
Your Tax ID — 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, W-2s, bank statements, and loan documents you've received. If you need to locate it, the IRS can send you a copy, or you can retrieve it from past tax returns or employer records.
The method depends on whether you're looking for a personal Tax ID (your SSN) or a business Tax ID (an EIN). Most people already have this number; they just need to know where to find it in paperwork they have at home.
Key Takeaways
- Your Social Security Number is your Tax ID as an individual and appears on your Social Security card, tax returns, W-2 forms, and bank statements.
- An Employer Identification Number (EIN) is a nine-digit Tax ID for businesses and is issued by the IRS when you register a business entity.
- You can retrieve a lost Tax ID by contacting the IRS directly at 1-800-829-1040 or by checking past tax returns filed with the IRS.
- The IRS can mail you a copy of your Tax ID verification letter, which takes 5 to 10 business days after you request it.
- If you've never had a Tax ID issued, you must apply through the IRS — individuals use their SSN automatically, and business owners must request an EIN.
Finding Your Social Security Number (Personal Tax ID)
Your Social Security Number is your Tax ID if you file taxes as an individual. It's a nine-digit number that appears on your Social Security card, which you received from the Social Security Administration. If you still have that card, your SSN is printed on the front.
If you can't locate your card, check any of these documents: your most recent tax return (Form 1040), a W-2 form from your employer, a 1099 form from a client or financial institution, your bank statements, your mortgage or loan paperwork, or any correspondence from the IRS. All of these show your full SSN or the last four digits.
If none of these documents are available, you can contact the Social Security Administration at 1-800-772-1213 to request a replacement Social Security card. They will mail it to you within 5 to 10 business days. You'll need to provide proof of identity (a driver's license or passport) and proof of citizenship or legal residency.
Finding Your Employer Identification Number (Business Tax ID)
If you own a business, your Employer Identification Number is a nine-digit Tax ID issued by the IRS. It looks like this: 12-3456789. You received this number when you first registered your business with the IRS, either by filing Form SS-4 or by applying online through the IRS website.
Check these places for your EIN: your business bank account statements, your business tax returns (Form 1120, 1120-S, or 1065), any correspondence from the IRS, your business loan documents, or payroll records if you have employees. The IRS also sends an EIN confirmation letter when you first receive the number — if you kept that letter, your EIN is on it.
If you can't find your EIN and you're not sure whether you ever received one, contact the IRS at 1-800-829-1040. Have your business name, address, and the date you started the business ready. The IRS can tell you whether an EIN was issued to you and can mail you a verification letter with the number on it.
Requesting a Tax ID Verification Letter from the IRS
The IRS issues an IRS Tax ID Verification Letter (also called a "Verification of Tax ID" or "EIN Verification Letter") that proves your Tax ID is valid and registered with the IRS. This letter is useful if you need to show proof of your Tax ID to a bank, lender, or government agency.
To request this letter, call the IRS at 1-800-829-1040 during business hours (Monday through Friday, 7 a.m. to 7 p.m. your local time). Have your Tax ID ready and tell the representative you need a verification letter. The IRS will mail it to the address on file, and it typically arrives within 5 to 10 business days.
You can also request the letter by mail. Send a written request to the IRS office for your state (the address is on the IRS website under "Contact Us"). Include your name, Tax ID, current address, and a statement that you need verification of your Tax ID. Mail it to the address listed for your state, and allow 2 to 3 weeks for delivery.
What to Do If You've Never Had a Tax ID Issued
If you're an individual who has never worked or filed taxes, you already have a Tax ID — your Social Security Number. You received this automatically when you were born or when you became a U.S. resident. You don't need to request one; it's already yours.
If you own a business and have never registered with the IRS, you need to request an Employer Identification Number. You can apply online through the IRS website (irs.gov), by phone at 1-800-829-1040, by fax, or by mail using Form SS-4. Online applications are processed immediately, and you receive your EIN right away. Phone and fax applications are processed within 4 business days. Mail applications take 2 to 3 weeks.
To apply for an EIN, you'll need your business name, business address, the type of business entity (sole proprietorship, LLC, corporation, partnership), the date you started the business, and your personal Social Security Number or Tax ID. The IRS will issue a nine-digit EIN and send you a confirmation letter.
Documents That Show Your Tax ID
| Document Type | Shows Your Tax ID | Where to Find It |
|---|---|---|
| Social Security Card | Social Security Number (personal) | Front of card |
| Form 1040 (Tax Return) | Social Security Number | Top of first page |
| W-2 Form | Social Security Number | Box 1 and top of form |
| 1099 Form | Social Security Number | Box 1 and top of form |
| Business Tax Return (1120, 1120-S, 1065) | Employer Identification Number | Top of first page |
| IRS EIN Confirmation Letter | Employer Identification Number | Body of letter |
| Business Bank Statement | Employer Identification Number | Account information section |
| IRS Correspondence | Social Security Number or EIN | Top of letter or notice |
Frequently Asked Questions
Is my Social Security Number the same as my Tax ID?
Yes, if you're an individual. Your Social Security Number is your Tax ID for tax purposes. If you own a business, you have both a Social Security Number and a separate Employer Identification Number (EIN). The EIN is your business Tax ID.
Can I look up someone else's Tax ID?
No. Tax IDs are private information. The IRS does not release Tax IDs for other people. If you need to verify someone's Tax ID for business purposes, they must provide it to you directly or authorize the IRS to share it.
What if I lost my Social Security card and can't remember my number?
Contact the Social Security Administration at 1-800-772-1213. They can tell you your number over the phone if you provide proof of identity. You can also request a replacement card, which arrives within 5 to 10 business days.
How long does it take to get an EIN if I just started a business?
If you apply online through the IRS website, you receive your EIN immediately. If you apply by phone, it takes 4 business days. If you mail Form SS-4, allow 2 to 3 weeks. Online is the fastest option.
Do I need a Tax ID if I'm self-employed?
You use your Social Security Number as your Tax ID if you're self-employed as a sole proprietor. If you form an LLC, S-corporation, or partnership, you'll need to request an Employer Identification Number from the IRS in addition to your SSN.