The Wisconsin Department of Revenue is protecting taxpayers using strong fraud protection safeguards. Those protection efforts include relying on tips from the public to help identify potential tax fraud. If you suspect an individual or business is not complying with the tax laws, you may report this information anonymously to us.

Online Referral Forms

• Report suspected fraud by completing Form P-626, Wisconsin Tax Information Referral Form.
• Report remote sellers that should be collecting Wisconsin sales or use tax by completing Form P-627, Wisconsin Remote Seller Referral Form.

When reporting any type of suspicious activity or identifying remote sellers that should be collecting sales or use tax, please provide as much information as possible to assist us in properly identifying the taxpayer and the reason the individual or business is being referred. Examples include: the name and address of the suspect or remote seller, why you think tax fraud is being committed, how much money is involved, any personal or financial information you have concerning the suspect, etc.

Submit by Email, Mail, or Fax:

Use the button in the upper right corner of the form to send by email. These forms may also be mailed or faxed to us using the information listed on each form.

Confidentiality Your identity can be kept confidential. However, it helps if you provide your contact information in case we have questions about the information you submitted. Under state privacy laws, we can't disclose what, if any, action we take based on information you provide. We do not offer rewards for reporting this information.

Additional Resources

Learn more about our efforts to protect taxpayers. If you are a victim of tax-related identity theft or a tax professional who has experienced a data breach or theft of client information, see our Identity Theft page for reporting instructions.

January 17, 2024