T The implementation of income tax article 21 (pph pasal 21) planning at pt x in 2024 is a crucial study in efforts to optimize tax savings. income tax article 21 itself is a tax levied on income in the form of salaries, wages, allowances, and other payments related to work received by domestic individual taxpayers. in practice, there are three main methods for calculating income tax article 21 commonly used by companies: the gross method, the gross up method, and the nett method. the gross method requires employees to bear their own income tax article 21 liability, while the gross up method involves the company bearing or providing a tax allowance equal to the income tax article 21 due. as for the nett method, the company also bears the income tax article 21 due on employee income, but without explicitly providing a tax allowance. the choice of these methods has different implications, not only for employees in terms of net income received but also potentially affecting the company\\\'s cost burden and ultimately impacting the calculation of corporate income tax (pph badan). this study aims to analyze in depth how the implementation of income tax article 21 calculations using the gross, gross up, and nett methods can influence the amount of corporate tax liability at pt x. tax, in general, is defined as a compulsory contribution that must be paid by individuals or companies to the state, is coercive, regulated by law, without direct reciprocal benefits, and is used to finance various public needs for the greatest prosperity of the people.