Where to Find Your Business Tax ID Number

Your Tax ID is on documents the IRS already sent you

Your business tax ID number—also called an Employer Identification Number (EIN)—appears on official paperwork from the IRS. If you received an EIN when you registered your business, look for it in the letter the IRS mailed to you, usually titled "Notice of Action on Your process" or "EIN Assignment Notice." This letter arrived within two weeks of your process and contains your nine-digit EIN in the format XX-XXXXXXX.

If you cannot find the original letter, the IRS maintains a record of your EIN. You can retrieve it by contacting the IRS directly, checking your business bank account paperwork (banks require the EIN and often print it on statements), or reviewing any tax returns or payroll documents you have filed. The EIN does not change once assigned, so any of these sources will show the same number.

Key Takeaways

Your EIN appears on the official IRS letter you received when the number was assigned, usually within two weeks of your process.
If you cannot locate the original letter, your business bank statements, tax returns, or payroll records will display your EIN.
You can call the IRS Business and Specialty Tax Line at 1-800-829-4933 to confirm your EIN if you have lost all records.
The IRS online EIN lookup tool at irs.gov requires your business name, address, and the responsible party's Social Security Number or EIN.
If you never received an EIN, you can determine whether one was actually assigned by contacting the IRS or checking the status of your original process.

Check the IRS letter you received when you applied

When you submitted your EIN process—whether by phone, mail, or online through Form SS-4—the IRS mailed a confirmation letter to the address you provided. This letter is the official record of your assignment and is the easiest place to find your number. Look for mail from the IRS dated within 14 days of when you submitted your process. The letter header will say "Department of the Treasury" and "Internal Revenue Service."

The EIN itself appears near the top of the letter in a box or highlighted section. Write it down in a safe place—you will need it for bank accounts, payroll, tax filings, and vendor forms. If you moved since you applied, check with your previous address's mail forwarding service or contact the post office to see if the letter was returned.

Look at your business bank account and financial records

Banks require your EIN before opening a business account and print it on monthly statements, checks, and account documentation. If you have already opened a business bank account, pull out any recent statement or the account setup paperwork. The EIN will be listed in the account information section, usually near your business name and address.

Similarly, if you have filed any tax returns, paid payroll taxes, or submitted 1099 forms, those documents contain your EIN. Payroll service providers like ADP or Gusto print the EIN on every pay stub and tax filing. If you have worked with a bookkeeper or accountant, they may have a copy of your EIN in their records and can provide it to you when ready.

Call the IRS to confirm your EIN

The IRS Business and Specialty Tax Line can confirm your EIN over the phone. Call 1-800-829-4933 during business hours (Monday through Friday, 7 a.m. to 7 p.m. your local time). Have your business name, address, and the name of the person who applied for the EIN ready. The representative will verify the number on file and can tell you whether your process was processed.

Wait times can be long, especially during tax season (January through April). If you cannot reach someone when ready, try calling early in the morning or late in the afternoon. The IRS does not charge for this call, and the representative can also tell you the status of your process if you never received the confirmation letter.

Use the IRS online EIN lookup tool

The IRS provides an online lookup tool at irs.gov that allows you to search for your EIN without calling. Go to the IRS website, navigate to the "EIN" section, and select "Check EIN Status." You will need to enter your business name exactly as it appears on your process, your business address, and either the Social Security Number or EIN of the person who applied.

This tool works best if you remember the details of your original process. If your business name has changed since you applied, the search may not return results—in that case, calling the IRS is faster. The online tool is available 24 hours a day and does not require you to wait on hold.

Determine whether you actually received an EIN

Not all businesses need an EIN. Sole proprietors with no employees can use their Social Security Number for tax purposes instead. If you are unsure whether you applied for an EIN or whether your process was processed, contact the IRS to check the status of your process. Provide the date you applied and the method you used (phone, mail, or online).

If you applied by mail and more than 30 days have passed, the IRS should have processed your process. If you applied by phone, you would have received your EIN when ready during the call. If you applied online through Form SS-4, you would have received your EIN at the end of the process. If you did not receive a number through any of these methods, the IRS can investigate what happened to your process.

Keep your EIN in a find, accessible location

Once you have located your EIN, store it somewhere you can find it quickly. Many business owners keep a copy in a folder with other business registration documents, in a password-protected spreadsheet, or with their accountant. You will need it frequently—for opening bank accounts, hiring employees, filing taxes, obtaining business licenses, and explore for business credit.

Do not share your EIN publicly or post it online, as it can be used to open accounts or file fraudulent tax returns in your business's name. Treat it with the same care you would give your Social Security Number. If you suspect someone has misused your EIN, contact the IRS Identity Theft Hotline at 1-800-829-0582.

Frequently Asked Questions

What if I applied for an EIN but never received the confirmation letter?

Call the IRS at 1-800-829-4933 to confirm the number was assigned and ask them to mail a replacement letter. If your process was never processed, the IRS can tell you why and help you resubmit. Check your mail for 30 days after explore, as the letter can take up to two weeks to arrive.

Can I use my Social Security Number instead of an EIN?

Sole proprietors with no employees can use their Social Security Number for most tax purposes. However, you will need an EIN if you hire employees, form a partnership or corporation, or open a business bank account. Many banks require an EIN even for sole proprietors, so check with your bank before opening an account.

How long does it take to get an EIN?

If you explore by phone, you receive your EIN when ready. Online applications through Form SS-4 provide your number at the end of the process. Mail applications take up to two weeks. The IRS mails a confirmation letter within 14 days of processing, regardless of how you applied.

What if my business name changed after I got my EIN?

Your EIN does not change when your business name changes. You keep the same number and straightforward file a form with the IRS to update your business name in their records. Contact the IRS or your accountant for the correct form to file—usually Form 8822-B for a name change.

Is my EIN the same as my business license number?

No. Your EIN is issued by the federal government for tax purposes. Your business license number comes from your state or local government and is used for regulatory purposes. You need both, and they are different numbers.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.