Gather the person’s full name, address, phone number, employer, and any known tax ID or business details
Collect specific facts, dates, amounts, and documents showing the suspected tax issue
Use IRS Form 3949-A to report suspected tax fraud or tax law violations
Mail the completed Form 3949-A to the IRS address listed on the form
Use IRS Form 211 if you are seeking a whistleblower award for qualifying information
Submit Form 211 to the IRS Whistleblower Office
Report suspected tax return preparer misconduct using IRS Form 14157
Report a tax return preparer’s misconduct involving your return using IRS Form 14157-A if applicable
Contact the IRS directly at 1-800-829-0433 for suspected tax fraud reporting guidance
Report identity theft or misuse of a Social Security number using the IRS Identity Theft resources
Keep copies of everything you submit for your records