Gather the taxpayer’s name, address, phone number, and Social Security number or EIN if known
Gather the business name, address, and type of business if applicable
Collect a clear description of the suspected fraud or tax law violation
Include dates, amounts, locations, and names of people involved if known
Save supporting documents, receipts, emails, screenshots, bank records, or other evidence
Report tax fraud to the IRS using Form 3949-A, Information Referral
Mail Form 3949-A to the IRS address listed on the form instructions
Report suspected abusive tax shelters or tax schemes using Form 14242 if applicable
Report tax return preparer misconduct using Form 14157 if applicable
Report tax return preparer fraud or injury caused by a preparer using Form 14157-A if applicable
Report whistleblower cases involving tax underpayments, fraud, or violations using Form 211 if the amount involved is substantial
Contact the IRS Whistleblower Office for Form 211 submission details
Report identity theft related to taxes using Form 14039 if your own tax information was misused
Call the IRS at 800-829-0433 for suspected fraud involving a tax return preparer
Use the IRS website to find current mailing addresses and form instructions
Keep copies of everything you submit
Do not send original documents unless specifically requested
Report immediate threats, violence, or other crimes to local law enforcement first