Sampling frequently is used by state and local tax authorities for sales and use tax audits. While stratified random sampling is the most widely used approach, each state has its own unique guidance for sample design, implementation, and extrapolation. It is beneficial for taxpayers to become familiar with sales and use tax audit sampling techniques used in jurisdictions where they operate. The state's sampling method will affect how the final audit assessment is ultimately determined.

This article discusses various types of sampling as well as methodologies of certain states.