As a result of a reform implemented in 2017, the National Revenue Administration was established in place of the existing tax administration, tax inspection, and the Customs Service. The tax administration was consolidated this way. Although the efficiency of collecting VAT, excise tax and fuel duty increased, there are still areas which require an analysis of the definition, statistical and legal scope, and an increase in the efficiency of enforcing compliance with both the European Union’s regulations on customs and tax and the Polish ones. The purpose of this paper is to analyse the functioning of regulations which have been applicable since 1 March 2017 and which concern customs and tax inspection of the assessment and collection of charges, which are related the import and export of goods onto the customs territory of the European Union, by the new authorities.