The dual aspect concept states that every business transaction requires recordation in two different accounts. This concept is the basis of double entry accounting, which is required by all accounting frameworks in order to produce reliable financial statements. The concept is derived from the accounting equation, which states that:
Assets = Liabilities + Equity
The accounting equation is made visible in the balance sheet, where the total amount of assets listed must equal the total of all liabilities and equity. One part of most business transactions will have an impact in some way on the balance sheet, so at least one part of every transaction will involve either assets, liabilities, or equity. Here are several examples:
- Issue an invoice to a customer: One part of the entry increases sales, which appears in the income statement, while the offset to the entry increases the accounts receivable asset in the balance sheet. In addition, the change in income triggered by the increase in sales appears in retained earnings, which is part of the equity section of the balance sheet.
- Receive an invoice from a supplier: One part of the entry increases an expense or an asset account, which can appear in either the income statement (for an expense) or in the balance sheet (for an asset). The offset to the entry increases the accounts payable liability in the balance sheet. In addition, the change in income triggered by the recordation of an expense appears in retained earnings, which is part of the equity section of the balance sheet.
If an organization were not to observe the dual aspect concept, it would use single-entry accounting, which is essentially a checkbook. A checkbook cannot be used to derive a balance sheet, so an entity would be limited to the construction of a cash-basis income statement.
If management wants to have its financials audited, it must accept the dual aspect concept and maintain its accounting records using double-entry accounting. This is the only format that auditors will accept if they are to issue opinions on financial statements.