job-order costing

Picture a custom furniture workshop. One customer orders a walnut dining table; another orders a set of oak bookshelves; a third orders a single rocking chair. Each order is different, uses different amounts of wood and labor, and takes a different number of hours. If the owner wants to know what each individual order actually cost — so she can price it sensibly and see which ones made money — she cannot just divide total monthly costs by the number of orders, because the orders are so unlike each other. She needs to track cost order by order. That is exactly what job-order costing does.

Job-order costing accumulates manufacturing costs separately for each distinct job or batch. A 'job' is one identifiable unit or batch of work — a custom table, a printing run of 500 wedding invitations, a single house built by a contractor, an audit engagement for one client. For each job, the firm directly traces the materials and labor it consumes, then adds a fair share of overhead (rent, supervision, machine depreciation) using a predetermined rate. Suppose a table uses 200 dollars of walnut, 10 labor hours at 25 dollars (250 dollars), and overhead applied at 15 dollars per labor hour (150 dollars): its total job cost is 600 dollars. The running record for each job is called a job cost sheet.

Job-order costing is the right system whenever output consists of distinct, custom, or small-batch products: construction, custom manufacturing, printing, shipbuilding, film production, and professional services like law, consulting, and accounting. Its opposite is process costing, used when identical units stream off a line continuously (gasoline, cement, soft drinks) and tracking cost per individual unit is impossible and pointless. The honest limitation: the accuracy of a job's cost depends heavily on how fairly overhead is spread across jobs — and overhead is allocated, not traced, so a poorly chosen allocation base can quietly distort which jobs look profitable.