One-Sided Errors vs Two-Sided Errors

For rectification purposes, the more practically important classification is not the four types above, but whether an error disturbs the agreement of the Trial Balance.

Two-sided errors (do NOT affect the Trial Balance's agreement) — both the debit and credit aspects are equally affected, so the Trial Balance still balances despite the error. These include: complete omission of a transaction (neither side was ever recorded, so nothing is unequal); an error of principle (the WRONG account is debited/credited, but by the correct, equal amount on both sides); posting an entry to the correct side of the wrong account of the SAME class (e.g., crediting Mala's account instead of Bala's, both personal accounts, same amount, same side); and compensating errors (each individual error may itself be one-sided, but together they cancel out).

One-sided errors (DO affect the Trial Balance's agreement) — only ONE side, or only ONE account, is wrongly affected, throwing the two sides of the Trial Balance out of agreement by exactly the amount of the error (or twice that amount, in certain cases — see the later section on rectifying one-sided errors). These include: wrong casting (totalling) of a subsidiary book; a wrong carry-forward from one page to the next; posting to the correct account but the wrong side; posting the correct amount to only one account and omitting the other entirely; and posting a different (wrong) amount to one account while the other account received the correct amount.

| Basis | Two-Sided Error | One-Sided Error |

|---|---|---| …