The Identification and Study of Causes on Difference between the Declared Profit Tax and Final Profit Tax of Non- governmental Legal Persons

Today، governments’ tax income is largely composed of tax on corporations. According to Tax Act، the corporation income tax is determined through deficit of some expenses as acceptable expenses from gross income. But there have been always differences between tax organization and taxpayer about how to determine the taxable income. In this research، besides exploration of the differences and their causes، we tried to investigate their effects on gap between the declared and final taxable income in non–governmental corporations. For doing so، some issues are studied including non–acceptable expenses، rejecting legal books and non-compliance of accepted accounting standards. To analyze the hypotheses، the needed information from tax cases of non–governmental corporations related to financial performance 1385– 1386 was gathered and then the differences between them were studied by»Paired T«analytical method. The results show that there have been significant differences between the declared and final taxable income due to inconsistency between accounting standards and tax rules