ENTaxes play a dual role in the economic mechanism of the developed western countries. From them the state not only collects its revenue (historically that is its fiscal function), but also indirectly stimulates its economy. It is reach more effective to realize economic policy by tax rates (payment for something, rates or lists of rates), sanctions (means of government influence, applied to the disturbers of established norms and regulations) and privileges that directly interfere economy. By giving tax privileges to business, a state guarantees capital flow to poorly developed, but promising regions, stimulates the competitiveness of enterprises and their production in inner and global markets. By reducing tax for profit reinvested (addition of profit from capital to the invested capital) to production, a state stimulates production development by releasing savings from taxation, it stimulates the reduction of consumption expenses. According to scientists' and specialists', the recognized economic valuation, tax system (the whole complex of collected taxes in the state, formed according to general taxation principles) is considered to be effective.In other words, it is "good" if it satisfies these requirements: guarantees planned regular tax revenue to the budgets of the state and local governments; stimulates the required level of production activity and personal consumption; allows to rationally coordinate financial interests of various levels (central and local) of government institutions according to the principle: own revenue source for every kind of the budget (this is achieved first of all by differentiating taxes according to the types of economy subjects and by clearly defining the competence in setting and collecting taxes of central and local governments). However, strict and inflexible tax laws should exist, they provide some alternatives in the taxation sphere. An enterprise has the right to choose one or another tax calculation and declaring way, specific privileges and stimulation ways. In other words, tax regulations allow the business enterprise to decide itself about applying some rules of taxation. It is possible to optimize payable taxes by properly choosing accounting and taxation rules. How this could be done by correspondingly changing tax rate is being analytically examined in this article. The effect of changes in tax rate (burden) on business development is also being examined, and the main factors influencing the distribution of this burden between consumers of goods (buyers) and producers (sellers) are presented.