Matching principle

In accrual accounting, the matching principle states that expenses should be recorded during the period in which they are incurred, regardless of when the transfer of cash occurs. Conversely, cash basis accounting calls for the recognition of an expense when the cash is paid, regardless of when the expense was actually incurred.

If no cause-and-effect relationship exists (e.g., a sale is impossible), costs are recognized as expenses in the accounting period they expired: i.e., when have been used up or consumed (e.g., of spoiled, dated, or substandard goods, or not demanded services). Prepaid expenses are not recognized as expenses, but as assets until one of the qualifying conditions is met resulting in a recognition as expenses. Lastly, if no connection with revenues can be established, costs are recognized immediately as expenses (e.g., general administrative and research and development costs).

Prepaid expenses, such as employee wages or subcontractor fees paid out or promised, are not recognized as expenses; they are considered assets because they will provide probable future benefits. As a prepaid expense is used, an adjusting entry is made to update the value of the asset. In the case of prepaid rent, for instance, the cost of rent for the period would be deducted from the Prepaid Rent account.

The matching principle allows for a more objective analysis of profitability. By recognizing costs in the period they are incurred, a business can see how much money was spent to generate revenue, reducing "noise" from timing mismatch between when costs are incurred and when revenue is realized.

Two types of balancing accounts exist to avoid fictitious profits and losses that might otherwise occur when cash is paid out not in the same accounting periods as expenses are recognized, because expenses are recognized when obligations are incurred regardless when cash is paid out according to the matching principle in accrual accounting. Cash can be paid out in an earlier or latter period than obligations are incurred (when goods or services are received) and related expenses are recognized that results in the following two types of accounts:

...
Wikipedia