Deadweight losses and administrative burdens are key factors considered when determining the efficiency of the tax system.

Deadweight losses refer to the reduction in economic efficiency that can occur when the equilibrium for a good or a service is not achieved, often due to taxes distorting market behavior. Administrative burdens are the costs associated with managing and complying with tax laws. Both are crucial in evaluating the efficiency of a tax system, as they impact the overall economic welfare and the ease with which taxes can be implemented and collected.