Chapter 11: Process Costing

Summary

Process costing is a product cost system that accumulates costs in processing departments and allocates them to all units processed during the period, including both completed and partially completed units. It is used by firms producing homogeneous products on a continuous basis to assign manufacturing costs to units in production during the period. Firms that use process costing include paint, chemical, oil-refining, and food-processing companies.

Process costing systems provide information so managers can make strategic decisions regarding products and customers, manufacturing methods, pricing options, overhead allocation methods, and other long-term issues.

Equivalent units are the number of the same or similar completed units that could have been produced given the amount of work actually performed on both complete and partially completed units.

The key document in a typical process costing system is the production cost report that summarizes the physical units and equivalent units of a production department, the costs incurred during the period, and the costs assigned to goods both completed and transferred out as well as to ending work-in-process inventories. The preparation of a production cost report includes five steps: (1) analyze physical units, (2) calculate equivalent units, (3) determine total costs to account for, (4) compute unit costs, and (5) assign total manufacturing costs.

The two methods of preparing the departmental production cost report in process costing are the weighted-average method and first-in, first-out (FIFO) method. The weighted-average method includes costs incurred in both current and prior periods that are shown as the beginning work-in-process inventory of this period. The FIFO method includes only costs incurred during the current period in calculating unit cost.

Most manufacturing firms have several departments or use processes that require several steps. As the product passes from one department to another, the costs from the prior department are transferred-in costs or prior department costs. Process costing with multiple departments should include the transferred-in cost as the fourth cost element in addition to direct materials, direct labor, and factory overhead costs.