The author addresses the issue of the influence of tax rate on income and consumption level within the scale of the whole economy as well as the degree to which it defines the scale of the budget. It is shown that tax rate does not influence the overall volume of revenues. It is stipulated that tax rate should be made dependent on the structure of the economy. The article demonstrates that personal income tax is a burden that differently affects various groups: those with the lowest incomes pay the taxes at the expense of consumption, for middle income groups taxes reduce consumption and savings while for the richest they only affect savings. Given this mechanism reductions in income tax rates differently affect different groups of tax payers. The analysis of the extent to which the income tax influences net incomes in Poland enables the author to state that the introduction of linear taxes would inflict losses on consumption goods market valued several billions euro, while the financial sector would record higher profits.