Entries Not Made at All
An entry not made at all is impossible to find on the trial balance, since it is not there (!). Your best bet is to maintain a checklist of standard entries, and verify that all of them have been made.
Entries to the Wrong Account
An entry made to the wrong account may be apparent with a quick glance at the trial balance, since an account that previously had no balance at all now has one. Otherwise, the best form of correction is preventive - use standard journal entry templates for all recurring entries.
Reversed Entries
An entry for a debit may be mistakenly recorded as a credit, and vice versa. This issue may be visible on the trial balance, especially if the entry is large enough to change the sign of an ending balance to the reverse of its usual sign.
Transposed Numbers
The digits in a number may have been switched. This is easy to find, since the underlying entry is unbalanced, and so should not have been accepted by the accounting software. If a manual system is being used, journal entry totals must be compared to the totals in the trial balance. This issue relates to the following one.
Unbalanced Entries
An unbalanced entry is listed last, since it is impossible in a computerized environment, where entries must be balanced or the system will not accept them. If you are using a manual system, then the issue will be apparent in the column totals of the trial balance. However, locating the exact entry is vastly more difficult, and will call for a detailed review of every entry, or at least of the totals in every subsidiary ledger that rolls into the general ledger.
Error Correction Best Practices
Whenever you correct an error, be sure to use a clearly labeled journal entry with supporting documentation, so that someone else can trace through your work at a later date.
Related Articles
How to Prepare a Trial Balance
The Difference Between an Unadjusted and Adjusted Trial Balance
The Difference Between the General Ledger and Trial Balance
