In manufacturing accounting, it is of very much importance to have a clear difference between cost and expense, though in general two terms are considered interchangeable.
The amount of cash paid or liability incurred for a commodity or service is referred to as the cost of that item. The commodity or service will obtain sale revenue in future. In other words, it represents the amount invested on a product or service, the benefit of which has not been fully utilized or consumed in connection with the realization of sale revenue.
Expense is that portion of cost which has been expired. As the commodity or service is consumed in the operation of a business enterprise consumed portion is converted into expense. This will be charged to the revenue of that period, in which it is consumed.
In nutshell expense represents that portion of the acquisition cost of goods or services, which have been expired, consumed or utilized in connection with the realization of revenue.
The difference can be explained with the help of following example: Suppose a machine is purchased on 1st January 2018 for $1,00,000. Transportation and installation charges come to $10,000. Its total cost is $1,10,000. Suppose annual depreciation of this asset is $10,000.
The cost of the asset after a year i.e., on 1st January 2019 will be $1,00.000 = (1,10,000 – 10,000) and $10,000 is that portion of cost which has been utilized during a year, This utilized portion is expense.