You can report suspected tax fraud or unreported income through the IRS Form 211, by mail, or through an online portal

The IRS has three main channels for reporting tax violations: the Form 211 (Application for Award for Original Information), a written letter to a specific IRS office, or the online whistleblower portal at www.irs.gov/whistleblower. Form 211 is the formal route and can result in a financial award if the IRS recovers more than $2 million from the case. A letter works if you want to report without pursuing an award. The online portal is fastest for initial submission but does not lead to awards.

You do not need to be a tax professional or have documentation ready before you contact the IRS. You can report with only what you know — a person's name, business name, approximate income, or specific transactions you witnessed. The IRS will investigate from there. Your report remains confidential; the IRS does not disclose your identity to the person you report.

Key Takeaways

  • Form 211 is the official way to report tax fraud if you want the IRS to consider you for a financial award, which ranges from 15 to 30 percent of money recovered above $2 million.
  • You can report anonymously by mail or through the online whistleblower portal without filing Form 211, though you will not be may be able to access for an award.
  • The IRS keeps your identity confidential and does not tell the person you report who made the report.
  • You do not need proof, receipts, or a complete case — the IRS investigates based on the information you provide.
  • Reporting takes weeks to submit but IRS investigation can take months or years, and you should not expect updates on the outcome.

Reporting with Form 211 and pursuing a financial award

Form 211 is a formal claim for an award. You file it with the IRS Criminal Investigation division or the office that handles the type of violation you are reporting. The form asks for your name, contact information, and a detailed description of what you know: the person or business involved, the nature of the violation, the approximate income or tax owed, and how you came to know this information.

If the IRS pursues the case and recovers more than $2 million in taxes, penalties, and interest, you may receive an award of 15 to 30 percent of what was recovered. Awards have ranged from a few thousand dollars to millions. However, the IRS does not may provide an award, and most reports do not result in one. The process is slow — investigations can take years, and the IRS does not notify you of progress or outcomes unless you are selected for an award.

You can obtain Form 211 from the IRS website or by calling 1-800-829-1040. Mail the completed form to the IRS Criminal Investigation office in your region. You can find the correct address on the IRS Criminal Investigation website or by calling the main IRS line. Include a cover letter with your name, phone number, and email address so the IRS can contact you if they need clarification.

Reporting by mail without pursuing an award

If you do not want to file Form 211 or pursue an award, you can send a letter directly to the IRS describing what you know. Address it to the IRS Criminal Investigation office in your region or to the IRS office that handles the type of violation — for example, the Employment Tax section if you are reporting unreported employee wages.

Your letter should include the person's or business's name, location, the nature of the violation, and any specific details you can provide: dates, amounts, account numbers, or how you learned the information. You can sign the letter with your real name or remain anonymous. If you sign it, include your phone number and email so the IRS can follow up. If you remain anonymous, the IRS will still investigate, but they cannot contact you for more information.

Mail the letter to the appropriate IRS office. You can find addresses on the IRS website under Criminal Investigation or by calling 1-800-829-1040. There is no deadline for reporting, and the IRS accepts reports about violations from any year.

Using the online whistleblower portal

The IRS whistleblower portal at www.irs.gov/whistleblower allows you to submit a report online. This route is faster than mail and keeps your submission in a digital record. You create an account, describe the violation, and upload any documents you have — though documents are not required.

The online portal does not lead to financial awards. It is designed for people who want to report a violation but do not want to pursue a claim or do not meet the Form 211 requirements (such as reporting violations under $2 million). The IRS still investigates reports submitted through the portal, but you should not expect notification of the outcome.

What information to include in any report

The more specific your report, the easier it is for the IRS to investigate. Include the person's or business's full name, address, phone number, and any business license or tax ID number you know. Describe what you believe is happening: unreported income, inflated deductions, cash-only transactions, offshore accounts, or employee wages paid under the table.

Provide dates, amounts, and specific examples if you can. For instance, instead of "they do not report all their income," say "they operate a cash business and I saw them deposit $50,000 in personal checks in March 2023 but report only $20,000 in quarterly income." If you have documents — bank statements, emails, receipts, or photographs — include copies. Do not send originals. If you do not have documents, report anyway; the IRS will investigate based on what you tell them.

Explain how you know this information. Are you a current or former employee? A customer? A family member? Someone who worked with the business? The IRS uses this to assess the reliability of your report and to decide whether to investigate.

What happens after you report

After you submit a report, the IRS Criminal Investigation division reviews it to decide whether to open an investigation. This review can take weeks or months. If they decide to investigate, they will gather financial records, conduct interviews, and build a case. This process typically takes one to three years, though complex cases take longer.

You will not receive updates on the investigation unless you filed Form 211 and the IRS recovers money. In that case, the IRS will contact you about the award after the case closes. If you reported anonymously or by letter, you should not expect to hear back.

The IRS does not disclose the outcome of investigations to the person who reported them. You will not learn whether charges were filed, whether the person paid back taxes, or what penalty they received. If you want to know the outcome, you can search public records — criminal cases are public, and some tax cases result in published court decisions — but the IRS will not tell you directly.

Frequently Asked Questions

Can I report someone anonymously?

Yes. You can mail a letter without signing your name, or use the online whistleblower portal without providing contact information. The IRS will still investigate. However, if you file Form 211 to pursue an award, you must provide your real name and contact information so the IRS can reach you about the award.

Do I need proof before I report?

No. You can report based on what you know or suspect. The IRS investigates and gathers evidence themselves. If you have documents, include them, but lack of documents does not prevent you from reporting.

What if I report my employer or a family member?

The IRS investigates all reports the same way, regardless of your relationship to the person. Your identity remains confidential, so the person will not know you reported them unless the IRS subpoenas you as a witness in a criminal case — which is rare and happens only if the case goes to trial.

How long does it take to get an award?

Awards are paid only after the IRS closes the case and recovers money. This can take two to five years or longer. The IRS will contact you with the award amount and payment timeline. Most awards are paid within a few months of case closure.

What if the person I report is not actually breaking the law?

The IRS investigates and determines whether a violation occurred. If they find no violation, no action is taken. You are not liable for reporting in good faith, even if the investigation finds nothing wrong.