A single overhead rate applied across an entire manufacturing facility simplifies the allocation of indirect manufacturing costs to products or services. This calculation involves dividing the estimated total overhead costs for the upcoming period by the estimated total amount of the cost driver. Common cost drivers include direct labor hours, machine hours, or direct labor cost. For instance, if estimated total overhead is $500,000 and estimated direct labor hours are 25,000, the resulting rate is $20 per direct labor hour.
Using a single rate streamlines cost accounting processes and offers a relatively simple approach to applying overhead. This can be particularly useful for smaller organizations or those with relatively homogenous products. Historically, it provided a cost-effective method when detailed tracking of overhead expenses was challenging or expensive. However, its accuracy depends heavily on the uniformity of production activities and the correlation between the chosen cost driver and actual overhead consumption.