Where and how to report suspected tax fraud

The IRS has a dedicated channel for reporting tax fraud: the Form 13909, also called the Fraud Referral Form. You file it with the IRS Criminal Investigation division, which is separate from the regular tax examination process. You can submit the form by mail, fax, or through an online portal on the IRS website.

The form itself is straightforward — it asks for details about the person or business you suspect, what fraud you believe occurred, and any documents you have. You do not need a lawyer, and you do not need to be certain; the IRS investigates based on suspicion. The agency receives thousands of these reports each year and prioritizes based on the amount of money involved and the type of fraud.

If you are reporting fraud by your employer, a business partner, or someone else you know, you can file anonymously. The IRS will not contact you to ask follow-up questions if you do not include your name. If you do include contact information, the IRS may reach out, but it will not disclose your identity to the person you reported.

Key Takeaways

  • File Form 13909 with IRS Criminal Investigation to report suspected tax fraud; you can submit it by mail, fax, or online.
  • You can report anonymously and do not need proof — suspicion and any supporting documents you have are enough to start an investigation.
  • The IRS prioritizes cases involving large amounts of money or organized schemes over small discrepancies.
  • If you are a whistleblower with inside knowledge of fraud and the IRS recovers money, you may be may have access to to a reward under the IRS Whistleblower Program.

What information to include on Form 13909

The form asks for the name, address, and identifying details of the person or business suspected of fraud. If you do not know the exact address, the city and state are enough to start. Include their Social Security number or Employer Identification Number if you have it; if not, describe what you know about them — their job, where they work, or how you know them.

Next, describe what you believe happened. Be specific: Did they underreport income? Claim false deductions? Hide money in offshore accounts? Operate a cash business and report no income? The more concrete your description, the easier it is for the IRS to investigate. If you have dates, amounts, or the names of other people involved, include those.

Attach copies of any documents that support your report — bank statements, emails, receipts, business records, or tax returns you have seen. Do not send originals; the IRS keeps what you submit. If you have a lot of material, include a cover letter that summarizes the main points and explains how you obtained the documents.

Submitting your report to the IRS

You can file Form 13909 three ways. The first is by mail: send it to the IRS Criminal Investigation office in your region. The IRS website lists the mailing address for each state. The second is by fax; again, the fax number is on the IRS website by state. The third is online through the IRS's secure form submission portal, which is the fastest route if you have scanned documents ready.

There is no filing fee, and you do not need to notify the person you are reporting. After you submit, you will not receive a confirmation letter or case number. The IRS does not update you on the status of your report or tell you whether an investigation was opened. This is intentional — it protects your identity and prevents the person under investigation from learning who reported them.

If you want a record that you filed, keep a copy of the form and any cover letter you sent, along with the date and method of submission. If you mailed it, consider sending it certified mail so you have proof of delivery.

The IRS Whistleblower Program and potential rewards

If you have inside knowledge of tax fraud — you worked for the company, you are a family member with access to records, or you are a former business partner — you may be may be able to access for the IRS Whistleblower Program. Under this program, if the IRS investigates your report and recovers more than $2 million in taxes, penalties, and interest, you can receive a reward of 15 to 30 percent of the amount recovered.

To pursue a whistleblower claim, file Form 211 (Application for Award for Original Information) instead of or in addition to Form 13909. Form 211 requires more detail and your contact information, because the IRS needs to be able to reach you and verify your role in uncovering the fraud. You must have original information — meaning you discovered it yourself, not from news reports or public records — and you must have a reasonable expectation that the IRS will recover money.

Whistleblower cases move slowly. The IRS may take years to investigate and recover funds. If money is recovered, you file a claim for your reward, and the IRS reviews it. Rewards are taxable income, so you will receive a Form 1099 and owe tax on the amount. Despite the timeline, whistleblower cases have paid out hundreds of millions of dollars to people who reported fraud.

What happens after you report

Once the IRS receives your report, it goes to Criminal Investigation, a specialized unit within the IRS. Criminal Investigation decides whether to open a case based on the seriousness of the suspected fraud, the amount of money involved, and the likelihood of recovery. Not every report results in an investigation — the IRS has limited resources and prioritizes cases with the highest impact.

If an investigation is opened, IRS agents will gather records, interview witnesses, and build a case. This can take months or years. If they find evidence of fraud, they may refer the case to the Department of Justice for criminal prosecution, or they may pursue civil penalties through the IRS examination process. You will not be told which path was taken or what the outcome was.

Criminal prosecution for tax fraud can result in fines and prison time. Civil penalties include back taxes, interest, and accuracy-related penalties of 20 to 75 percent of the underpaid tax, depending on the type of fraud. The person or business under investigation has the right to defend themselves in court.

Reporting fraud by a tax professional or preparer

If you suspect a tax preparer, accountant, or attorney of fraud — for example, they encouraged you to claim false deductions or helped you hide income — you can report them to the IRS using Form 13909. You can also file a complaint with the Treasury Inspector General for Tax Administration (TIGTA), which oversees IRS employees and contractors.

If the preparer is a Certified Public Accountant (CPA) or enrolled agent, you can also report them to their state licensing board. Each state has a board that disciplines CPAs and enrolled agents for misconduct. The IRS website lists contact information for state boards by state.

If you paid the preparer to prepare a fraudulent return, you may have a civil claim against them for damages. Consider consulting a lawyer about your options, especially if you have already been audited or assessed penalties because of the fraudulent return.

Frequently Asked Questions

Do I need to report fraud if I am the victim?

If someone filed a fraudulent tax return using your name or Social Security number, report it to the IRS and file Form 14039 (Identity Theft Affidavit) instead of Form 13909. This alerts the IRS that you are a victim and protects your account. You should also file a report with the Federal Trade Commission and consider placing a fraud alert on your credit report.

What if I suspect fraud but do not have documents?

You can still file Form 13909. Include what you know — dates, amounts, names of people involved, and how you learned about the suspected fraud. The IRS will investigate based on your report alone. Documents strengthen your report, but they are not required to file.

Can my employer retaliate against me for reporting tax fraud?

Federal law prohibits retaliation against employees who report tax fraud or other illegal activity. If you are fired, demoted, or harassed after reporting, you may have a legal claim. Document what happened and consider consulting an employment lawyer or contacting the Occupational Safety and Health Administration (OSHA), which handles whistleblower complaints.

How long does it take for the IRS to investigate?

There is no set timeline. Some investigations take months; others take years. The IRS does not update you on progress. If you filed under the Whistleblower Program and expect a reward, the process is typically longer because the IRS must verify your information and calculate the recovery amount before paying you.

Will the person I report know it was me?

Not if you file anonymously. If you include your name and contact information, the IRS will not disclose your identity to the person under investigation, but they may learn who reported them through the discovery process if the case goes to court. If you are concerned about retaliation, file anonymously or consult a lawyer about your options.