Trial balance

A trial balance is a list of all the general ledger accounts (both revenue and capital) contained in the ledger of a business. This list will contain the name of each nominal ledger account and the value of that nominal ledger balance. Each nominal ledger account will hold either a debit balance or a credit balance. The debit balance values will be listed in the debit column of the trial balance and the credit value balance will be listed in the credit column. The trading profit and loss statement and balance sheet and other financial reports can then be produced using the ledger accounts listed on the trial balance.

The process was first described by Luca Pacioli in the 1494 work Particularis de Computis et Scripturis. Although it did not use the term, he essentially prescribed a technique similar to a post-closing trial balance.

The purpose of a trial balance is to prove that the value of all the debit value balances equal the total of all the credit value balances. If the total of the debit column does not equal the total value of the credit column then this would show that there is an error in the nominal ledger accounts. This error must be found before a profit and loss statement and balance sheet can be produced.

The trial balance is usually prepared by a bookkeeper or accountant who has used daybooks to record financial transactions and then post them to the nominal ledgers and personal ledger accounts. The trial balance is a part of the double-entry bookkeeping system and uses the classic 'T' account format for presenting values.

A trial balance only checks the sum of debits against the sum of credits. That is why it does not guarantee that there are no errors. The following are the main classes of errors that are not detected by the trial balance.

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