Where to report suspected tax fraud

The IRS has a dedicated unit for fraud reports called the Criminal Investigation Division. You can report suspected tax fraud through the IRS Form 3949-A (Information Referral), which goes to the IRS Criminal Investigation office, or through the online whistleblower portal at www.irs.gov/fraud. The online portal is faster and requires no paperwork.

You can also call the IRS Criminal Investigation tip line at 1-800-366-4484. This line accepts reports about tax evasion, identity theft, money laundering, and other financial crimes. If you have documents or evidence, you can mail them to the IRS Criminal Investigation Division at the address listed on Form 3949-A, but the online portal usually processes reports more quickly.

If the fraud involves identity theft — someone filing a tax return using your Social Security number — report it to the IRS Identity Theft Hotline at 1-800-908-4490 in addition to the Criminal Investigation Division. Identity theft cases move through a separate system and require different documentation.

Key Takeaways

  • The IRS Criminal Investigation Division accepts fraud reports through an online portal at www.irs.gov/fraud, by phone at 1-800-366-4484, or by mailing Form 3949-A.
  • Reports involving identity theft should also go to the IRS Identity Theft Hotline at 1-800-908-4490, which handles cases where someone filed a return using your Social Security number.
  • The online portal is the fastest route and requires no forms; you describe the suspected fraud and upload documents if you have them.
  • You do not need to be a tax professional or have complete proof to file a report — the IRS investigates based on the information you provide.
  • If you are a whistleblower with inside knowledge of significant tax fraud, the IRS Whistleblower Program may award you a percentage of taxes recovered above $2 million.

What information the IRS needs from you

The IRS asks for the name, address, and Social Security number or employer identification number of the person or business you suspect of fraud. If you do not have all of this, provide what you can — the IRS can often locate someone with partial information. Include the type of fraud you suspect: unreported income, false deductions, payroll tax evasion, or something else.

Describe what you observed or learned about the fraud. If you have documents — bank statements, emails, receipts, business records, or a copy of a suspicious tax return — upload them to the online portal or include them with a mailed report. The more specific your information, the more likely the IRS can investigate. For example, "I know they have unreported cash income" is less useful than "They told me they made $50,000 in cash sales last year but reported only $10,000."

You do not need to provide your own name or contact information when you report through the online portal, though you can if you want the IRS to contact you with updates. Anonymous reports are accepted and investigated.

The difference between the Criminal Investigation Division and the Whistleblower Program

The Criminal Investigation Division investigates all types of tax fraud and can result in criminal charges, civil penalties, or both. Reports go into a queue and are prioritized based on the amount of money involved and the type of fraud. Most reports do not result in prosecution — the IRS may simply assess back taxes and penalties — but serious cases can lead to felony charges.

The IRS Whistleblower Program is separate and applies only to cases involving substantial tax underpayment. To may have access to, the tax underpayment must exceed $2 million, or if the person earns over $200,000 per year, the underpayment must exceed $2 million. If the IRS recovers taxes based on your report, you receive between 15 and 30 percent of the amount collected. This program is designed for people with inside knowledge — employees, accountants, or business partners who have direct evidence of fraud.

If you think you may may have access to for the Whistleblower Program, file Form 211 (Application for Award for Original Information) with the IRS Whistleblower Office. You will need detailed documentation and may want to consult a tax attorney, because the process is more formal than a standard fraud report.

What happens after you report

When you submit a report through the online portal or by phone, you receive a confirmation number. The IRS does not typically send updates on individual cases unless you are part of the Whistleblower Program. Criminal Investigation cases can take months or years to complete, and the IRS does not announce outcomes to the person who reported.

If you provided your contact information and the IRS needs clarification, they will reach out. Otherwise, assume your report has been filed and is under review. The IRS receives thousands of fraud reports each year and prioritizes cases based on the dollar amount and complexity.

If the fraud involves your own tax account — for example, someone filed a return using your identity — the IRS will contact you directly about next steps. You may need to file an amended return or provide additional documentation to resolve the issue.

Reporting fraud committed by a tax professional

If you suspect a tax preparer, CPA, or enrolled agent has committed fraud or misconduct, you can report them to the IRS Office of Professional Responsibility. File Form 13909 (Complaint Regarding Tax Return Preparer) with the IRS. This is different from reporting a client's fraud — it addresses whether the tax professional themselves violated the law or ethical rules.

You can also report a tax preparer to your state's licensing board. CPAs are regulated by state boards, and enrolled agents are regulated by the IRS. State boards can suspend or revoke licenses, which is often faster than a criminal investigation.

Reporting fraud to other agencies

Depending on the type of fraud, you may also report to other agencies. If the fraud involves identity theft, report it to the Federal Trade Commission at www.identitytheft.gov. If it involves a financial institution, report to the Consumer Financial Protection Bureau or the bank's regulator. If it involves a business that is defrauding customers or employees, you may report to your state's attorney general or the FBI.

You can report to multiple agencies at once — there is no requirement to go to the IRS first. Each agency investigates within its own jurisdiction, and information sometimes flows between them.

Frequently Asked Questions

Do I have to give my name when I report tax fraud?

No. The IRS online portal and tip line both accept anonymous reports. You can provide your name and contact information if you want updates, but it is not required. Anonymous reports are investigated the same way as named reports.

What if I am not sure whether something is actually fraud?

Report it anyway. The IRS investigates and determines whether fraud occurred. You do not need to be certain — describe what you observed and let the IRS decide. False reports are rare and the IRS does not penalize people for reporting in good faith.

Can I report my employer for not paying payroll taxes?

Yes. Payroll tax evasion is a serious federal crime. Report through the Criminal Investigation Division using the online portal or Form 3949-A. If you are an employee and your employer is not paying taxes withheld from your paycheck, you can also file a complaint with the Department of Labor Wage and Hour Division.

How long does it take the IRS to investigate a fraud report?

There is no set timeline. Some cases are resolved in months; others take years. The IRS prioritizes based on the amount of money involved and the complexity of the case. You will not receive regular updates unless you are part of the Whistleblower Program.

What if the person I reported is my spouse or family member?

You can still report. The IRS investigates regardless of the relationship between the reporter and the person reported. If you are concerned about consequences, remember that reports can be anonymous.