The purchaser becomes responsible for remitting use tax when the purchaser takes ownership or control of the good or service. Ordinarily, the retailer is responsible for collection of the tax, but if the retailer is not required by law to collect the tax or the retailer fails to do so, the purchaser is then responsible for remitting use tax. In many cases, these are purchases made from an out-of-state supplier not collecting Iowa sales tax on goods or services that are for use in Iowa. Use tax is most often imposed after the sale takes place and only on goods and services on which sales tax was not collected. The tax is imposed when the first use of a service occurs, or potentially could occur, in Iowa, or when the tangible personal property or specified digital product is delivered in Iowa. The seller of the goods or services is responsible for collecting, reporting, and remitting the sales tax. Sales tax is imposed on the sales price of the sale of tangible personal property, specified digital products, or taxable services at the time the sale takes place.