How do I report tax fraud or a tax preparer scam to the IRS?

If you suspect tax fraud or have been victimized by a tax preparer scam, there are several reporting channels. For tax fraud (someone cheating on their taxes): file Form 3949-A (Information Referral) with the IRS. You can also report fraud to the IRS Whistleblower Office if the tax owed exceeds $2 million, which may entitle you to 15-30% of the amount collected. For tax preparer fraud or misconduct: file a complaint with the IRS Office of Professional Responsibility (OPR) for enrolled agents, CPAs, or attorneys. For non-credentialed preparers, file Form 14157 (Complaint: Tax Return Preparer). If the preparer filed a return without your knowledge or changed your return after you signed it, file Form 14157-A (Tax Return Preparer Fraud or Misconduct Affidavit). For IRS impersonation scams: report to the Treasury Inspector General for Tax Administration (TIGTA) at 1-800-366-4484 or tigta.gov. For identity theft using your SSN: file Form 14039 (Identity Theft Affidavit) with the IRS. Also report to: the FTC at reportfraud.ftc.gov, your state attorney general, and the state board that licenses the preparer (Board of Accountancy for CPAs, Bar Association for attorneys).