In a job order costing system, job cost sheets constitute the subsidiary ledger for which main control account?

Introduction / Context:
Cost accounting systems track the cost of producing goods or services. In a job order costing system, costs are accumulated by individual jobs, and job cost sheets are used to record materials, labor and overhead for each job. Behind the summarized ledger accounts sit detailed subsidiary records. This question asks you to identify which main control account uses job cost sheets as its subsidiary ledger.

Given Data / Assumptions:

• The costing system is job order costing, not process costing.
• Each job has its own job cost sheet that records materials, labor and overhead applied.
• There are control accounts for raw materials, work in process, finished goods and manufacturing overhead.
• Subsidiary ledgers support control accounts by providing detailed breakups.

Concept / Approach:
In job order costing, total costs for all incomplete jobs at a point in time represent the balance in the Work in Process (WIP) control account. Each job cost sheet supports this control account by showing the accumulated cost for that particular job. The sum of all job cost sheets for uncompleted jobs should equal the WIP control account balance. Raw materials, finished goods and overhead each have separate subsidiary records, but these are not job cost sheets. Therefore, the correct answer is the Work in Process control account.

Step-by-Step Solution:
Step 1: Recall that job cost sheets track the cost of individual jobs until they are completed. Step 2: Recognize that costs on jobs that are still in production represent work in process. Step 3: Identify that the Work in Process control account summarizes the total cost of all ongoing jobs. Step 4: Link job cost sheets as the detailed breakdown that forms the subsidiary ledger to this control account. Step 5: Conclude that option B, Work in process control account, is the correct match.

Verification / Alternative check:
You can verify the relationship using the accounting equation for job order costing. When materials and labor are assigned to a job, entries debit Work in Process and credit stores or wages payable. Overhead is also applied to Work in Process. The job cost sheet for each job accumulates these debits. When a job is completed, its total cost moves from Work in Process to Finished Goods. At any point, summing the costs on job sheets for uncompleted jobs should match the Work in Process control account balance, confirming that job cost sheets form the subsidiary ledger for this account.

Why Other Options Are Wrong:
Option A is wrong because the Raw materials inventory account is supported by a materials ledger that shows quantities and values of each material item, not by job cost sheets. Option C is wrong because Finished goods inventory is supported by records of completed units and their costs, often summarized by product type rather than by job cost sheets for uncompleted jobs. Option D is wrong because Manufacturing overhead control is supported by schedules of actual overhead expenses and applied overhead, not by job cost sheets, which simply receive overhead allocations.

Common Pitfalls:
Students sometimes mistakenly associate job cost sheets with finished goods because the sheets show the final cost of a job once it is complete. However, the primary function of the job cost sheet is to track costs while the job is in progress. Another pitfall is to confuse subsidiary ledgers for materials and overhead with job cost sheets. Keeping a clear mental map of which records support which control accounts will help avoid such errors.

Final Answer:
Job cost sheets constitute the subsidiary ledger for the Work in process control account in a job order costing system.