With the decentralisation of state management, decisions have been taken to strengthen the financial autonomy of public-law organisations. Decentralisation, together with the new area of competence of local governments, has become a very important element of the process of educating citizens in the area of finance, especially in the area of tax management. This article is devoted to the problem of proper use of real estate tax by the gmina self-government, hence its functionality in the context of the law in force and the use of this law by the inhabitants of the gminas and local authorities. Within the scope of decisions influencing the amount of income of the gmina self-government from the real estate tax, there are residents, who most often determine the taxable area they use. Next, the decision-making and executive bodies, acting jointly, decide on the subjective and material scope of the tax. It should also be noted that the functionality of this tax is strongly influenced by the residents who contact their representatives in the gmina authorities and officials who consistently perform their duties and control the properties of the area to be taxed. Citizens’ knowledge of public finances, especially of the rules determining the size of liabilities towards the state budget or public-law partnerships functioning within it, including budgets of local governments, translates into financial security not only of local budgets but also of household budgets. The study used research among taxpayers of this tax. It analysed the legal dimension and the income from this tax in a selected region of the Republic of Poland. The main objective of the study, apart from the assessment of the functionality of real estate tax, is to build a model of real estate tax management that takes into account, first of all, the principle of tax justice.