Errors of Commission
The errors which are committed due to wrong posting of transactions, wrong totaling or balancing of the accounts, wrong casting of the subsidiary books, or wrong recording of amount in the books of original entry, etc. are called errors of commission.
For example: Radha Hans Traders paid Rs. 25,000 to Preethi Traders (a supplier of goods). This transaction was correctly recorded in the cashbook. But while posting to the ledger, Preethi's account was debited with Rs. 2,500 only. This constitutes an error of commission. Such an error is of clerical nature and most of the errors of commission affect in the trial balance.