[header] How to report tax fraud anonymously [title] Know the warning signs of tax fraud. [step] Tax fraud involves the under-payment of any kind of taxes, including income, sales, property, or other business taxes. Tax fraud costs everyone by forcing the government to raise taxes or cut services. 
[substeps] While there is no definitive way to spot fraud, there are some common warning signs that someone may be committing fraud. Using cash to purchase items that are hard to trace and easy to sell.