Identification of elements of benchmark tax system (indirect taxes benchmark) and tax expenditures is a necessary prerequisite for the implementation of the concept of the tax expenditures in the budget process. Their identification is complicated by the lack of a generally accepted conceptual model of the tax benchmark and, consequently, – generally accepted criteria for qualifying a particular provision of tax legislation as an element of such benchmark or tax expenditures. Given the above, the application of the concept of tax expenditures to the analysis of indirect taxes is determined as the purpose of the article. To achieve this goal, the most controversial aspects of the concept of tax expenditures are considered: the problems of their identification and measurement, as well as the contradictory consequences of its implementation. Peculiarities of application of the concept to the study of tax reliefs for indirect taxes – universal and specific excises are analyzed. The main elements of the benchmark for the VAT and deviations from it are identified, on the identification of which there are both consensus and disagreement among scientists and practitioners from different countries. The existing approaches to the qualification of reduced VAT rates and exemptions from payment in the public interest in the EU member states and other countries are analyzed, arguments in favor of their identification are proposed, taking into account the harmonization of this tax. The existing conceptual approaches to the identification of elements of the benchmark and tax expenditures of the least studied in this context specific excises and the peculiarities of their application in different countries are outlined. The definition of the main elements of the benchmark and tax expenditures of harmonized excise taxes is argued. Based on the analysis of the reports of the State Tax Service of Ukraine on tax reliefs, that are losses of budget revenues, and other tax reliefs, the main elements of the benchmark and tax expenditures for VAT and excise tax in Ukraine are highlighted. Regarding the latter, such elements are defined for all excisable goods, as well as for some of their groups – alcoholic beverages, tobacco products and energy products. It is established that in Ukraine the composition of the elements of the benchmark and tax expenditures of excise tax on alcoholic beverages and tobacco products can be justified according to the directions of their use, which create or do not create negative externalities, while for excise tax on energy products the theory of optimal taxation should be also taken into account . Common problems in the distribution of VAT and excise tax reliefs between the report on tax reliefs, that are losses of budget revenues, and the report on other tax reliefs have been identified. It is established that such problems are caused by the uncertainty of the Ukrainian methodological basis for identifying elements of the benchmark tax system and tax expenditures by providing information on budget losses from the use of tax reliefs without publishing the methodology of their measurement and definition in normative documents of the specified categories (basic notions of the concept of tax expenditures).