Service cost centre costing standard sets rules for measurement, allocation, presentation, and disclosure in cost statements. Cost Accounting Standard 13 establishes principles and methods for measuring, assigning, presenting and disclosing the cost of a service cost centre in cost statements. It requires identifiable service cost centres to be treated as distinct cost objects, with cost determined from direct and indirect attributable costs, subject to rules on contractor services, inter-unit and inter-company transfers, outside-party services, and allocation on equitable and consistent bases where direct traceability is not possible. Finance costs and imputed costs are excluded, while subsidies, grants, credits, recoveries, abnormal cost and penalties are reduced or excluded as specified. The standard also prescribes presentation as separate cost heads and disclosure of material bases, variances, related party services and other specified items.