Yes, in most business situations you have to give out your EIN. Federal law requires you to include your Employer Identification Number on tax returns, provide it to clients who need to file information returns on payments to you, print it on every W-2 you issue, and share it with banks opening a business account. You can refuse requests from parties who have no tax-reporting or regulatory reason to ask, but those situations are the exception.
An EIN Is Not a Secret Number
This is where most business owners start from the wrong assumption. An EIN is a public-facing business identifier, not a confidential number like a Social Security Number. The Department of Health and Human Services has stated directly that “EINs are not considered private and they may be freely exchanged by employers and others.”1U.S. Department of Health and Human Services. Frequently Asked Questions About the National Standard Employer Identifier (EIN) Tax-exempt organizations already have their EINs searchable through the IRS Tax Exempt Organization Search tool alongside copies of their annual returns.2Internal Revenue Service. Tax Exempt Organization Search
That doesn’t mean you should hand it out to anyone who asks. It means the legal framework treats EIN requests very differently from SSN requests. There is no federal privacy statute shielding the number from disclosure, and the situations where you have to share it far outnumber the situations where you can decline.
When You Have to Share It
Tax Filings
Federal law requires every person filing a return, statement, or other document to include their identifying number, which for a business is the EIN.3Office of the Law Revision Counsel. 26 USC 6109 Identifying Numbers That covers every IRS filing your business touches — income tax, employment tax, excise tax, and correspondence with the agency. State revenue departments need it for income tax, sales tax, and payroll filings. Failing to include your EIN can trigger a penalty of $50 per omission, up to $100,000 in a calendar year.4Office of the Law Revision Counsel. 26 USC 6723 Failure to Comply With Other Information Reporting Requirements
If your business imports goods, U.S. Customs and Border Protection uses your EIN as your importer of record number for entry paperwork, duty calculations, and compliance tracking.5U.S. Customs and Border Protection. Importer Numbers
Banks and Lenders
You cannot open a business bank account without an EIN. Federal anti-money laundering rules require banks to run a Customer Identification Program before opening any account, collecting at minimum the entity’s name, address, and taxpayer identification number.6FDIC. FFIEC BSA/AML Examination Manual – Customer Identification Program The bank then verifies that information against documents like articles of incorporation or a government-issued business license. Lenders use the same number to pull your business credit profile when you apply for a loan or line of credit.
Clients Who Send You a W-9
When a client pays you $600 or more during the year for services, they generally need to file Form 1099-NEC reporting that payment to the IRS.7Internal Revenue Service. Instructions for Forms 1099-MISC and 1099-NEC To prepare that form, they send you a W-9 asking for your business name, address, and taxpayer identification number. This is the most common EIN request freelancers and contractors get, and refusing has real cost.
If you don’t provide your TIN on the W-9, the payer must begin backup withholding at 24% on all future payments to you.8Internal Revenue Service. Publication 15 (2026), (Circular E), Employer’s Tax Guide That 24% goes to the IRS and only comes back to you when you file your return and claim it as a credit. You also face your own penalty for failing to furnish a TIN.4Office of the Law Revision Counsel. 26 USC 6723 Failure to Comply With Other Information Reporting Requirements A client asking for a W-9 isn’t being nosy; they’re complying with the same tax code you are.
Employees on Their W-2
Every employer must print their EIN in Box b of every W-2 they issue. The IRS instructions are explicit: show the EIN assigned to you, do not truncate it, and do not substitute a prior owner’s number.9Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026) Your employees need it to file their personal returns. Without it, their filings can stall and refunds get delayed.
When You Can Say No
The situations where you can decline all share one trait: the requester has no tax-reporting or regulatory reason to need the number. Common examples:
- Marketing or lead-generation companies building business databases.
- Sellers of goods when no 1099 or other information return will be filed on the transaction.
- Unsolicited calls or emails claiming to be from the IRS. The IRS does not cold-call businesses to demand an EIN.
- Individuals or companies with no financial or contractual relationship with your business.
When someone persists, ask them to identify the specific tax form or legal requirement driving the request. A legitimate requester — a client, bank, or agency — can always point to the form or regulation. If they can’t, that’s your answer. For basic verification that your business legally exists, many states maintain public business registries that confirm entity status without exposing a tax ID.
Sole Proprietors: Trade Your SSN for an EIN
Sole proprietors face a privacy problem the others don’t. Without an EIN, every W-9 you hand a client exposes your Social Security Number. That SSN then sits in the client’s files, their accountant’s files, and their cloud storage indefinitely. A breach at any point compromises your personal identity.
Applying for an EIN through the IRS is free and takes minutes online. Once you have one, you can use it on W-9s, 1099 filings, and business credit applications in place of your SSN. The IRS lets sole proprietors use either number, so the switch creates no compliance issues. If you send W-9s to multiple clients each year, it’s one of the simplest privacy moves available.
If Someone Misuses Your EIN
EIN fraud usually shows up in one of two ways: someone files a fraudulent tax return using your business’s EIN, or someone files fake W-2s under your number to claim refunds. Warning signs the IRS flags include being unable to e-file because a return with your EIN is already on file, or a rejected extension request because a duplicate return exists.10Internal Revenue Service. Identity Theft Information for Businesses
If you suspect misuse, the IRS directs you to complete and submit Form 14039-B, the Business Identity Theft Affidavit, with all requested supporting documents and a signature to avoid processing delays.11Internal Revenue Service. Report Identity Theft for a Business Move quickly. Fraudulent filings under your EIN trigger IRS notices, disrupt processing of your real return, and create a paper trail that can take months to untangle.
The EIN itself isn’t confidential, but it can still be used against you. Share it when the law or a legitimate business relationship requires it, decline when neither applies, and that balance is really all the protection available.