Form 3949-A, the IRS “Information Referral,” is the form you use to report a person or business you suspect of cheating on federal taxes. You fill in what you know about the suspected violator and the conduct, then send it to the IRS, which uses the tip as a lead when deciding whether to open an audit or investigation.1Internal Revenue Service. About Form 3949-A, Information Referral You can file it under your own name or anonymously, and filing it does not, by itself, entitle you to any reward.
What You Can Report
The form covers a broad range of federal tax violations. Typical uses include:
- Unreported income, including cash paid off the books, undisclosed offshore accounts, and unreported digital asset gains.2IRS.gov. Form 3949-A – Information Referral
- False exemptions or deductions, such as claiming dependents the filer isn’t entitled to or inventing deductions to shrink a tax bill.1Internal Revenue Service. About Form 3949-A, Information Referral
- Failure to withhold employment taxes, including paying workers under the table, skipping Social Security or Medicare withholding, or misclassifying employees as independent contractors to avoid payroll tax.2IRS.gov. Form 3949-A – Information Referral
- Kickbacks or bribes disguised as legitimate business expenses.
- Unreported profits from organized crime or gambling.
When a Different Form Is the Right One
Form 3949-A is for general tax fraud tips. Three common situations call for something else, and using 3949-A instead will slow you down:
- If someone used your personal information to file a fraudulent return, use Form 14039, the Identity Theft Affidavit.3Internal Revenue Service. When to File an Identity Theft Affidavit
- If a paid tax preparer committed fraud or misconduct on your return, use Form 14157 with Form 14157-A.4Internal Revenue Service. Make a Complaint About a Tax Return Preparer
- If you suspect a nonprofit or other tax-exempt organization is violating the terms of its exemption, use Form 13909.5Internal Revenue Service. IRS Complaint Process – Tax-Exempt Organizations
What to Put on the Form
The more concrete detail you give, the more useful the referral is. The form asks for information about the person or business you’re reporting:
- Legal name and street address of the individual or business.
- A taxpayer identification number, meaning a Social Security Number for an individual or an Employer Identification Number for a business. Including this significantly raises the chance the IRS can match the referral to actual tax records.2IRS.gov. Form 3949-A – Information Referral
- The specific tax years involved, and dollar amounts if you know them.2IRS.gov. Form 3949-A – Information Referral
The form also has a comments section. Use it to describe what the person did, how you learned about it, and any specific transactions or documents that back up your account. If you have copies of relevant records, correspondence, or financial documents, attach them. Fields left blank make it easier for a reviewer to set the referral aside.
How to Submit It
The IRS offers an online filing option through the Form 3949-A Information Referral tool on irs.gov.1Internal Revenue Service. About Form 3949-A, Information Referral If you’d rather mail it, print the completed form and any supporting documents and send the package to:
Internal Revenue Service
PO Box 3801
Ogden, UT 844092IRS.gov. Form 3949-A – Information Referral
Filing Anonymously
You do not have to identify yourself. Section C, which asks for the reporter’s name and contact information, says on the form itself that this information is not required for the IRS to process the report. Giving your details makes it easier for the IRS to follow up with questions, but that call is yours.2IRS.gov. Form 3949-A – Information Referral
Confidentiality If You Do Sign
If you provide your name, federal law shields it. Under 26 U.S.C. § 6103, tax return information, including whether a particular taxpayer is under investigation, is confidential, and IRS employees are barred from disclosing it to third parties.6Office of the Law Revision Counsel. 26 USC 6103 – Confidentiality and Disclosure of Returns and Return Information The IRS protects the identity of the person who filed the referral to the full extent the law allows.
What Happens After You File
Once the IRS receives your form, it evaluates the tip and decides whether to open an audit or an investigation. Don’t expect a status update. The confidentiality rules under 26 U.S.C. § 6103 mean the IRS cannot tell you whether it audited the person you reported, what it found, or whether any tax or penalty was assessed.6Office of the Law Revision Counsel. 26 USC 6103 – Confidentiality and Disclosure of Returns and Return Information
Filing Form 3949-A also does not, on its own, put you in line for a whistleblower award. It is a referral, not an award application.
If You Want a Whistleblower Award, File Form 211
To be considered for a financial reward when your information leads the IRS to collect taxes, penalties, or interest, you have to file Form 211, Application for Award for Original Information, with the IRS Whistleblower Office.7Internal Revenue Service. Submit a Whistleblower Claim for Award The amount, and whether an award is mandatory or discretionary, depends on the size of the case and other statutory conditions set out in 26 U.S.C. § 7623.8Office of the Law Revision Counsel. 26 USC 7623 – Expenses of Detection of Underpayments and Fraud Certain Treasury and other federal employees who learned the information through their official work are not eligible.
The Risk of a False Report
Only file what you actually believe to be true. Under 18 U.S.C. § 1001, knowingly submitting a materially false statement to a federal agency is a felony punishable by up to five years in prison.9Office of the Law Revision Counsel. 18 USC 1001 – Statements or Entries Generally That covers fabricated allegations on the form itself and forged supporting documents. The IRS treats these referrals as serious government filings, not casual tips.