A trial balance is a bookkeeping or accounting report that lists the balances in each of an organization's general ledger accounts. (Accounts with zero balances will likely be omitted.) The debit balance amounts are listed in a column with the heading "Debit balances" and the credit balance amounts are listed in another column with the heading "Credit balances." The total of each of these two columns should be identical.

In a manual system a trial balance was commonly prepared by the bookkeeper in order to discover whether math errors and/or some posting errors were made. Today, bookkeeping and accounting software has eliminated those clerical errors. This means that the trial balance is less important for bookkeeping purposes since it is almost certain that the total of the debit and credit columns will be equal.

However, the trial balance continues to be useful for auditors and accountants who wish to show 1) the general ledger account balances prior to their proposed adjustments, 2) their proposed adjustments, and 3) all of the account balances after the proposed adjustments. These final balances are known as the adjusted trial balance, and these amounts will be used in the organization's financial statements.

Neither the unadjusted trial balance nor the adjusted trial balance is a financial statement and neither trial balance is distributed to anyone outside of the accounting and auditing staff. In other words, the trial balance is an internal document.