The Books and the Bank Were $1,047.55 Apart. The Answer Was a List of 23 Entries.

A client's balance sheet showed a bank balance of $5,391.25. Their bank reconciliation for the same date showed $4,343.70. The difference was $1,047.55, and nobody could say where it came from.

Our first answer was wrong

The first conclusion we reached was the comfortable one: the books are right, so the reconciliation must be wrong. It sounded reasonable. It was also untested.

Then we checked it against the one document outside the system: the bank statement. It said $4,343.70. The reconciliation was right and the books were wrong. A confident answer, including our own, is a guess until it has been checked against something the system did not produce.

Find the list, not the culprit

A difference that is exact to the cent is almost never rounding, and almost never one big mistake that someone would have noticed. It is usually a set of real entries that are in the wrong place: the wrong account, the wrong period, or the wrong year.

So instead of asking who made a mistake, we searched for entries that add up to exactly $1,047.55. There were 23 of them. All were February 2025 bank items. All had been entered recently, with the year typed as 2026.

Because they were dated a year in the future, they counted towards the balance sheet for the later date but did not belong to any statement the reconciliation had covered. Together they came to $1,047.55, to the cent.

The second typo that hid the first

One more mistake kept this hidden for longer than it should have been. The statement date on that month's reconciliation had been typed as 2023. Any report that lined up reconciliations by date placed it in the wrong year, so the month that should have exposed the 23 entries looked as if it had never been reconciled at all.

Nobody did anything strange. Someone entered a stack of old bank statements in one sitting, and the year on the date field was off. That is the most ordinary way books go wrong.

Once the 23 dates and the one statement date were corrected, the balance sheet matched the bank.

Checks that find this in any accounting system

1. Start from the bank statement. Decide which side is right by comparing both with the statement, not with each other.
2. Look for a list that adds up to the difference. Filter the bank account for entries the reconciliation did not clear, then look for a group, often from one month or one supplier, whose total matches exactly.
3. Sort by transaction date and look at both ends. Entries dated in the future, or years in the past, stand out immediately at the top and bottom of a sorted list.
4. Compare the transaction date with the date it was entered. A February 2025 payment entered in November 2026 is normal. One dated 2026 that is supposed to be from February is not. Most systems keep an entry or creation date you can export next to the transaction date.
5. Check the reconciliation dates themselves. A statement date with the wrong year moves a whole month out of sight.
6. Do the same with the next difference, not just this one. Once you know the pattern, the same batch of data entry usually has more of it.