The amount of personal income tax according to the current legislation is 13 %. If your income subject to taxation has amounted to 500 thousand rubles over the past year — this means that the employer withheld 65 thousand rubles of tax. If you apply for a property tax deduction, document the fact of the purchase of housing worth, for example, 1 million. rub., then your taxable income for the past reporting period will be reduced by 500 thousand. rub. As a result, the tax paid to the budget will be completely returned to you — 65 thousand. rub., and an unused tax benefit (500 thousand. rub.) will be transferred to the next reporting period (year).