Expense account

An expense account is the right to reimbursement of money spent by employees for work-related purposes. Some common expense accounts are: administrative expense, amortization expense, bad debt expense, cost of goods sold, depreciation expense, freight-out, income tax expense, insurance expense, interest expense, loss on disposal of plant assets, maintenance and repairs expense, rent expense, salaries and wages expense, selling expense, supplies expense and utilities expense.

To increase an expense account, it must be debited. To decrease an expense account, it must be credited. The normal expense account balance is a debit. In order to understand why expenses are debited, it is relevant to note the accounting equation, Assets = Liabilities + Equity. Expenses show up under the equity portion of the equation because equity is common stock plus retained earnings and retained earnings are revenues minus expenses minus dividends. Expenses are considered temporary accounts in this equation, because at the end of the period, expense accounts are closed. Because expense accounts decrease the credit balance of owner’s equity, expenses must be debited.

At the end of the year, expense accounts need to be closed, or zeroed out. Expense accounts need to be closed because they are temporary, meaning that they pertain only to a given accounting period and won’t carry over into the next one. When expense accounts are closed, they close to another temporary account, known as Income Summary. So, the expense accounts must be credited, and the Income Summary will be debited. The net loss or gain in this account transfers to Retained Earnings, which is a permanent account.

Contra accounts are accounts that are related, yet separate from its particular account. A contra expense account will behave in the opposite way a normal expense account will; instead of debiting to increase, a contra account must credit to increase. Instead of crediting to decrease, it will be credited to increase. An example of a contra expense account is Purchase Returns and Allowances.

In the United States, the use of an expense account can be traced back to George Washington, who chose to forego a salary and relied on an expense account to cover his purchases during his military leadership in the American Revolution.

Under today's tax laws of the United States, expense accounts are treated as either "accountable" or "unaccountable". Accountable expense accounts are subject to a variety of restrictions. Accountable expense accounts are subject to a variety of Internal Revenue Service regulations. There must be a documented business purpose for the account. Spending from the account must be documentable, typically by means of receipts. Any money entrusted to the employee from the account that is not spent for business purposes and accounted for must be returned to the employer.

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