The purpose of this article is the presentation of issues related to hybrid instruments. We will primarily focus on the analysis of various aspects of hybrid instruments and entities. The use of these instruments produces fairly significant tax implications that have specific effects on the holdings of capital group companies operating worldwide, and these companies therefore frequently use hybrid instruments to optimise their tax policies. This study identifies numerous issues that may be critical to these firms when designing an optimal tax policy, without losing sight of the fact that fiscal policy is an essential determinant of the financial standing of a company. In particular, this article discusses the tax consequences of various policies given the different tax systems used in the European Union countries, focusing upon the specific conditions and implications of the Polish tax system.