순자산증가개념의 포괄주의 소득세 도입방안에 관한 연구

The purpose of this paper is to review the difference between the current income tax law and the accretion concept's global tax system, which is called the ideal income tax system, This paper also aims to present directions for which parts of the accretion and global tax system should be accommodated and in what order to minimize the side effects of the introduction of the system and to design the tax in a better way. The current income tax law basically has a source concept’s schedular tax system, but some accretion concepts such as capital gain taxation and categorical global system are accepted. As the taxable income is gradually expanding, the scope of tax base is not significantly different from that of countries adopting the global system. However, in the current income tax law, it is difficult to tax new types of income due to the limitations of the schedular tax system, and the tax compliance cost is increasing due to the unclear income classification. In addition, there is a problem that the systematic coherence of the tax system is damaged as income that cannot be taxed in the schedular tax system is included as the subject of gift tax. On the other hand, the current income tax law is not suitable for the accretion concept as capital gains such as stocks are taxed according to the realization principle, not the market-to-market taxation or accrual principle. In order to solve this problem, when introducing the elements of the accretion concept's global taxation into the current income tax system, in the short term, it is necessary to alleviate the problems that occur in the schedular tax system or to introduce the elements of the global system gradually. Through this, it is necessary to design the tax system close to the global tax system without significantly changing the current tax system, thereby preventing tax confusion caused by rapid changes in the tax system. In the mid- to long-term, it is necessary to gradually convert the current schedular tax system to a global tax system. In addition, it is necessary to consider designing an income tax system that meets the accretion concept through the combination of accrual taxation of interest income such as bond’s discount, market-to-market taxation such as listed stocks, and retrospective accrual regime other than listed stocks.