The article is devoted to the peculiarities of the accounting policy of expenses (taxes, fees, payments and other mandatory deductions) that affect profitability (profitability) construction contractors, as subjects of investment and construction activities. It is noted that a significant factor in the formation of the cost of construction products (works and services) are, including costs in the form of tax deductions and other mandatory payments (transport tax, payments for mandatory civil liability insurance of vehicles (CTP), land tax) on the fixed assets of production available on the balance sheet (owned) of organizations. Some features of accounting and taxation of leasing property (real and movable) are described. It is stated that the legislation DOIs not clearly regulate the issue of attributing the costs of the above-mentioned tax deductions to the cost of production, performance of works and provision of services. The reasoned confirmation of the conditions (principles) of attribution (reflection) in the accounting of the costs of the above taxes, depending on the features (types) and conditions of the work performed by construction organizations, is given. Different approaches are noted in determining the system of accounting for income (profit) and expenses in the estimated pricing (used in determining the price of a government contract), as well as accounting and tax accounting. The assessment of these differences negatively affecting the financial position of contractors is given.